CRYRING@ESR:
A study group report
Darmstadt, July 26, 2012
Michael Lestinsky1 , Norbert Angert1 , Ralph Bär1 , Ralph Becker1 , Mario Bevcic1 , Udo Blell1 ,
Walter Bock1 , Angela Bräuning-Demian1 , Håkan Danared2 , Oleksiy Dolinskyy1 ,
Wolfgang Enders1 , Mats Engström3 , Achim Fischer1 , Bernhard Franzke1 , Georg Gruber1 ,
Peter Hülsmann1 , Anders Källberg3 , Oliver Kester1,4 , Carl-Michael Kleffner1 ,
Yuri A. Litvinov1 , Carsten Mühle1 , Bernhard Müller1 , Ina Pschorn1 , Torsten Radon1 ,
Heinz Ramakers1 , Hartmut Reich-Sprenger1 , Dag Reistad3 , Galina Riefert1 ,
Marcus Schwickert1 , Ansgar Simonsson3 , Jan Sjöholm3 , Örjan Skeppstedt3 , Markus Steck1 ,
Thomas Stöhlker1,5 , Wolfgang Vinzenz1 , and Horst Welker1
1
GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
European Spallation Source ESS, SE-221 00 Lund, Sweden
3
Fysikum, Stockholm University, SE-106 91 Stockholm, Sweden
4
Institut für Angewandte Physik, Goethe-Universität Frankfurt, 60438 Frankfurt a. M., Germany
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Helmholtz-Institut Jena, 07743 Jena, Germany
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Contents
Subject of this Study
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1 Introduction
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2 Scientific Motivation
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3 CRYRING@ESR: Location in the Target Hall at GSI
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4 CRYRING@ESR: List of Parameters
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5 CRYRING as Test Bench for FAIR
5.1 Stand-Alone Operation of CRYRING . . . . . . . . . . . . . . . .
5.2 Accelerator Controls . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Beam Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4 UHV Control and Interlock System . . . . . . . . . . . . . . . . .
5.5 Radiation Safety and Access Control System . . . . . . . . . . .
5.6 Controls for Technical Infrastructure . . . . . . . . . . . . . . . .
5.7 Preparation for FAIR Commissioning . . . . . . . . . . . . . . . .
5.7.1 Development and Test of Special Commissioning Software
5.7.2 Training of Operating Staff . . . . . . . . . . . . . . . . .
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6 Proposed Construction Cycle
6.1 Conditions for the Project Start . . . . . . . . . . . . . . . . .
6.2 CRYRING Disassembly and Transport . . . . . . . . . . . . .
6.3 Preparation of the CRYRING Cave at GSI . . . . . . . . . .
6.4 Preparation of the Technical Infrastructure . . . . . . . . . .
6.4.1 Access Control . . . . . . . . . . . . . . . . . . . . . .
6.4.2 Cooling Water . . . . . . . . . . . . . . . . . . . . . .
6.4.3 Electricity . . . . . . . . . . . . . . . . . . . . . . . . .
6.4.4 Others . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.5 Fast ESR Beam Ejection and Transport to CRYRING . . . .
6.6 Completion of the CRYRING Components . . . . . . . . . .
6.6.1 Magnets . . . . . . . . . . . . . . . . . . . . . . . . . .
6.6.2 Power Converters . . . . . . . . . . . . . . . . . . . . .
6.6.3 Beam Diagnostics . . . . . . . . . . . . . . . . . . . .
6.6.4 Radio-Frequency Components . . . . . . . . . . . . . .
6.6.5 UHV . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.6.6 CRYRING Control System . . . . . . . . . . . . . . .
6.7 Assembly of CRYRING and Injection Beam Lines . . . . . .
6.7.1 Preparation of Magnetic Components: Fiducialization
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CONTENTS
6.7.2
6.7.3
Procurement of Mechanical Parts . . . . . . . . . . . . . . . . . . . . . . .
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 Project Steering
7.1 Time Schedule . . . . . . . . . . . . . . . . . . . . . . . . . .
7.2 Cost and Manpower Requirements . . . . . . . . . . . . . . .
7.3 Project Structure: Installation and Operation . . . . . . . . .
7.4 Possible Sources of Funding . . . . . . . . . . . . . . . . . . .
7.5 Swedish contributions to the installation of CRYRING@ESR
7.6 Swedish Participation in Experiments at FAIR . . . . . . . .
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Bibliography
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A Letters of Support
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Subject of this study
The Swedish in-kind contribution for FAIR includes the storage ring CRYRING, built by the
Manne Siegbahn Laboratory in Stockholm. The international FAIR project has decided to accept
this Swedish proposal as the central storage ring for the FLAIR facility for experiments with
slow and even trapped anti-protons and exotic ions. Recently, in the context of the preparation
of CRYRING for the transport to Darmstadt, which is expected to happen still within 2012,
the idea was born to ask GSI to check for the option to install the CRYRING in the vicinity
of the ESR storage ring inside the Target Hall. Such a project would closely be related to an
early realization of the FLAIR facility not included into the Modularized Start Version of the
FAIR project. The research with exotic ions as proposed for the FLAIR facility could already
now being pursuit with this installation and at a later stage the extension to experiments with
slow anti-protons would be possible on the basis of only moderate investments.
Following the advice of the GSI scientific council and of the executive board of GSI, the
atomic physics department of GSI has been assigned to form a working group∗ in order to come
up with a proposal for installing CRYRING within the current Target Hall at GSI and provide
a reliable estimate of the required resources to install CRYRING at ESR. The results obtained
by this study group for both the resources needed as well as the possible location of CRYRING
at GSI are described within the current document. In addition, a comprehensive overview of
the physics opportunities which can be addressed by the combination of CRYRING and ESR
will be given. Detailed description of physics cases is the subject of a dedicated “Physics Book:
CRYRING@ESR”, the actual version of which is attached to this document. Since we still
expect a considerable amount of additional contributions from various collaborations interested
in the realization of CRYRING@ESR, the physics book is being continuously updated. Once
completed, it is planned to publish “Physics Book: CRYRING@ESR” as a regular article in a
peer-reviewed scientific journal. Moreover, we added a dedicated chapter “CRYRING as a Test
Bench for FAIR” to emphasize the important and possibly even indispensable role of CRYRING
as a test bench for many FAIR relevant accelerator related developments. There, emphasis is
given to the operation of CRYRING as a stand-alone facility equipped with its own ion source
and injector. The CRYRING@ESR is supported by various physics communities as well as by
all FAIR storage ring collaborations which is reflected by dedicated support letters. The latter
are attached to the Appendix of the current document.
∗
N. Angert, A. Bräuning-Demian, H. Danared, W. Enders, M. Engström,
B. Franzke, A. Källberg, O. Kester, M. Lestinsky, Yu. A. Litvinov, D. Reistad,
A. Simonsson, J. Sjöholm, M. Steck, and Th. Stöhlker
5
6
CONTENTS
Chapter 1
Introduction
Storage ring experiments in the realm of atomic and nuclear physics with heavy ions and exotic
nuclei contribute substantially to the success of the present GSI SIS18/ESR facility and form
one of the essential cornerstones of the future facility for antiproton and ion research FAIR. The
corresponding experiments at FAIR are being prepared by the following international collaborations SPARC (Stored Particles Atomic Physics Research Collaboration), FLAIR (Facility for
Low-Energy Antiproton and Ion Research), ILIMA (Isomeric beams, LIfetimes, and MAsses),
ELISE (ELectron-Ion Scattering Experiment), and EXL (EXotic nuclei studied in Light-ion induced reactions). The contributions by the Swedish and German partners in these collaborations
are significant and indispensable. In the case of Sweden, the strong engagement is manifested by
the provision of the Stockholm CRYRING facility as a Swedish in kind contribution for FAIR,
where it will serve as the central storage ring installation within the FLAIR building. For this
purpose substantial resources have already been invested to adapt CRYRING to its future role
at FAIR. The delivery of CRYRING is expected to begin at the end of 2012.
Because the new storage rings facilities are not part of the modularized start version (MSV)
of the international FAIR project (because of the high civil construction cost for the storage
ring complex NESR and FLAIR), it has been decided to maintain the operation of ESR —
as documented by the Green Paper: The Modularized Start Version ∗ — in order to assure a
persisting expertise in storage ring operation and physics and to allow substantial R&D work
related to FAIR and in particular to FLAIR. Since CRYRING will be delivered to FAIR by the
end of this year, the question needs to be answered is to what extent can CRYRING already
be installed at the existing GSI Target Hall or, alternatively, whether it should be stored in
containers for the next decade or longer.
In view of FAIR, the operation of CRYRING at the existing ESR facility would exhibit
various important advantages:
• CRYRING as a FAIR test facility could be essential for FAIR relevant R&D projects, in
particular with respect to accelerator related developments of instrumentation and controls: beam diagnostics, detector development, synchronization, efficient coupling of accelerators and storage rings, software development etc. Keeping in mind that there will be
a break of at least 1.5 years in SIS18 operation, CRYRING would play a very important
role by using it as a stand-alone facility.
• CRYRING will help secure expertise of the personnel by providing otherwise not available
training opportunities.
• CRYRING would open novel and unique physics opportunities with large discovery potential and it would allow the existing storage ring collaborations connected to FAIR to
continue.
7
8
Chapter 1. Introduction
Moreover, the mid and long term physics perspectives of CRYRING@ESR are exciting.
Once the MSV of FAIR is accomplished, a transfer beamline for anti-protons and exotic nuclei
from the CR to the ESR-CRYRING storage ring complex can be considered. In this way two
fully commissioned storage rings, ESR and CRYRING, would be available at a very early stage
for experiments using slow anti-protons at FAIR. Additionally, the experiments in the research
areas of nuclear- (EXL, ELISe, ILIMA) and hadron physics will profit from this scenario using
rare isotope beams from the FRS/ESR facility and later on from the FAIR accelerator chain.
Therefore, in view of both the MSV as well as the full version of the FAIR project, installing
CRYRING at ESR already now has the potential to save considerable resources. It will provide
a platform for prototyping FAIR technologies which is inevitably required and will consequently
minimize the amount of time typically needed for the commissioning of these complex storagering facilities.
∗
Green paper [1]: “All these developments are also of particular relevance for future
prospects of the SPARC physics programme which concentrates on storage rings and
traps, and will become possible with Module 4. For the realization of this programme
the ESR storage ring and the HITRAP facility need to be maintained in operation
at GSI until they shall be surpassed by Module 4.”
Chapter 2
Scientific Motivation
In the following we concentrate on the ion part of the physics program to be addressed at
CRYRING@ESR. It will cover to a large extent the research with ions as proposed for the
FLAIR facility (module 4 of the MSV). Note, at a later stage only a moderate investment for a
transfer beam line would be required to transport anti-protons to CRYRING via the ESR and
to perform the anticipated FLAIR experiments with slow or even trapped anti-protons.
The exploration of the unique properties of stored and cooled beams as provided by heavy
ion storage rings has opened novel and fascinating research opportunities in the realm of atomic
and nuclear physics research. For the particular case of the ESR storage ring, this has been
demonstrated in experiments addressing e.g. the 1s Lamb shift in heavy ions, the hyperfine
splitting in hydrogen-like heavy atoms, the investigation of dielectronic recombination in heavy,
few-electron ions, direct mass measurements of short-lived radionuclides or by studying rare
nuclear decay modes such as the bound-state β-decay or the orbital electron capture decay [2–7].
World-wide, ESR is the only storage ring that provides access to all naturally occurring elements
up to the most extreme case of fully stripped uranium. Charge states and energies (4 MeV/u
to 500 MeV/u) can be tailored according to the requirements of the experiment [8]. Moreover,
intense beams of highly charged in-flight synthesized radioisotopes are at the experimentalist’s
disposition. Likewise, CRYRING was operated at the Manne-Siegbahn Laboratory (MSL) in
Stockholm with great success [9–15] however with much lighter ions or heavy ions of lower charge
state.
CRYRING is optimized for operation in an ion energy range of ∼ 14 MeV/u down to
300 keV/u or lower. Both rings, ESR and CRYRING operate in complementary ion energy
ranges, and CRYRING thus bridges the gap between the lowest stable operation of ESR (∼
4 MeV/u) and the HITRAP facility [16] with highly charged ions close to or even at rest whereby
preserving the high luminosity, characteristic for stored ion beams. Moreover, for the low energy regime below 10 MeV/u, the properties of CRYRING along with its instrumentation have
several advantages compared to ESR such as its compactness and the excellent UHV vacuum
conditions of < 10−11 mbar. By combining ESR and CRYRING, the entire energy range from
500 MeV/u almost down to rest will be available for experiments dealing with intense beams of
highly charged ions and exotic nuclei.
CRYRING@ESR will be the only facility world-wide that provides low-energy highly charged
stable beams and beams of rare isotopes with a free choice of the charge state, including bare ions.
Radioisotopes synthesized in a target after SIS18 can be purified from unwanted contaminants
either with the present fragment separator FRS or alternatively directly in the ESR by employing
its high resolving power [16, 17]. Of particular scientific interest are stable ions and artificially
synthesized nuclides dressed with few electrons or fully stripped. In such elementary ionic
systems the physics topic under investigation is not masked or hampered by many-body effects
9
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Chapter 2. Scientific Motivation
or unwanted spectator electrons. The interpretation of the experiments is thus straightforward
and without ambiguity. In addition, the inverse processes of many fundamental atomic and
nuclear reaction and decay mechanisms only become experimentally accessible if corresponding
vacancies in the atomic shell are available. Examples of these inverse effects include radiative
recombination (inverse of photoeffect), dielectronic capture (inverse of autoionization), bound
state beta decay (inverse of nuclear electron capture, EC) or nuclear excitation by electron
capture (inverse of internal conversion).
Low-energy phase space of cooled ions provide extremely well-defined experimental conditions for precision spectroscopy experiments (electrons, ions, and photons). At the same time,
compared to ions at rest, orders of magnitude higher luminosity in collision experiments using
low-energy ions in a storage ring is achieved due to the repeated interaction of the stored ion
beam with a target (gas, free electrons, laser). These luminosities may be comparable to or even
exceed those obtainable in single-pass fixed-target experiments while the dilute targets induce
only a minimum amount of angular and energy straggling which can be compensated by beam
cooling and guarantee for single collision conditions.
For atomic collision studies, another appealing aspect is the very strong perturbation to
the target atoms due to the impact of the slow highly charged ions with conditions far from
equilibrium. CRYRING operates in a particular interesting energy range for nuclear reactions,
that is at the Coulomb barrier and in the astrophysically relevant Gamow window of p- and rpprocesses of nucleosynthesis. The swift low-energy beam also makes the detection and monitoring
of primary and secondary ions either in a destructive manner with particle detectors or in a
non-destructive manner down to the level of single particles by means of Schottky techniques
experimentally much easier. Hereby, the storage ring itself serves as a high-resolution magnetic
heavy ion spectrometer. The dynamic range that is covered with the various experimental
techniques covers the span from single stored ions, detected by means of Schottky noise analysis
up to beams at the space charge limit.
As stated in a previous section, the capabilities for future research on atomic, nuclear,
and astrophysics with a combined CRYRING and ESR facility will be outlined in a dedicated
“Physics book: CRYRING@ESR” which is in preparation. The current draft of the physics
book is appended to this document. Moreover, since by the installation of CRYRING@ESR
a substantial part of the heavy ion program as foreseen at FAIR for NESR and FLAIR can
already be addressed, we also like to refer to the already positively evaluated physics programs
as described in the FAIR documents of the contributing collaborations (SPARC [18], FLAIR
[19], EXL [20], ILIMA [21], and ELISe [22]).
Chapter 3
CRYRING@ESR: Location in the Target
Hall at GSI
For a cost efficient solution of CRYRING@ESR, utilizing existing space, technical installation,
and ion beamlines is mandatory. A suitable location for setting up CRYRING at GSI can
be found at Cave B, which is almost ideal. We illustrate the envisaged realization of CRYRING@ESR in Figure 3.1. Cave B is located downstream of ESR and a transport beam line for
ions is presently available. Further, the cave is of the required size which means required construction changes could be performed without interfering with other experimental installations.
Modifications to the cave construction can be done at moderate cost, as this essentially requires
only moving available concrete blocks. However, the technical infrastructure and facilities, such
as cooling water, electricity, or air conditioning, have to be adapted to the requirements of
CRYRING along with its beamlines.
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Chapter 3. CRYRING@ESR: Location in the Target Hall at GSI
Figure 3.1. The proposed topology for CRYRING@ESR in the Target Hall of GSI. Several options
for a reassembly of CRYRING have been investigated. We propose locating the setup in Cave B
as the least invasive and most cost efficient solution. The modified CRYRING with injection beam
lines is shown with blue lines. See also Figure 6.1 for a detailed view of the modified Cave B.
Chapter 4
CRYRING@ESR: List of Parameters
A detailed description of CRYRING (LSR) foreseen for the operation with antiprotons as
planned for the envisioned program of the FLAIR collaboration has been given within the
TDR “LSR - Low-energy Storage Ring” [23]. In the following we summarize the CRYRING
parameters as they are relevant for the operation with heavy ions at the current SIS/ESR facility (Table 4.1). In addition, the most important in-ring installations as they are required for
experiments are given below:
• Electron cooler
• Internal jet target
• Transversal electron target
• Collinear laser setups
• Schottky pickups
• Particle counters
• Recoil ion, electron, and photon spectrometers
Table 4.1. CRYRING parameters as they are relevant for the operation with heavy ions at the
current SIS/ESR facility.
Circumference
51.63 m
Rigidity at injection for ions (antiprotons, protons)
1.44 Tm (0.80 Tm)
Highest possible injection energy for p̄, p
30 MeV
— for
12 C6+
— for
238 U92+
24.7 MeV/u
(238 U89+ )
14.8 MeV/u (13.9 MeV/u)
Lowest rigidity
0.054 Tm
Lowest energy
charge exchange limited
Magnet ramping (deceleration and acceleration)
7 T/s, 4 T/s, or 1 T/s
Vacuum pressure (N2 equiv.)
10−11 –10−12 mbar
Beam injection
multi-turn and fast
Beam extraction
slow and fast
Ion sources for stand-alone operation
yes (300 keV/u, q/A > 0.25)
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Chapter 4. CRYRING@ESR: List of Parameters
Chapter 5
CRYRING as Test Bench for FAIR
5.1
Stand-Alone Operation of CRYRING
As described in Chapter 3 the installation of CRYRING in the Target Hall in combination with
the fragment separator (FRS) and the Experimental Storage Ring (ESR) would represent an
attractive, novel facility for atomic and nuclear physics experiments. But CRYRING would
also offer an ideal opportunity for testing important technical developments for FAIR under
operating conditions. These tests could be performed even during longer shut down periods
of SIS18, i.e. without beam from ESR. This is because CRYRING has its own injector and,
therefore, can be operated as a stand-alone system. The low energy RFQ injector delivers ions
with charge-to-mass ratio q/A ≥ 0.25 at a fixed specific energy of 0.3 MeV/u. The ion beam
can be pulsed with repetition frequencies up to 5 Hz and pulse lengths smaller or equal 0.5 ms.
Similar to SIS18, multiturn injection is applied to attain higher circulating beam currents.
The stand-alone operation would preferably be applied for the commissioning of CRYRING
after the completion of the ring assembly and the successful commissioning of all ring systems
without ESR beam.
For the test of FAIR technologies and components the use of the RFQ-injector seems to be
the most suitable mode of operation. Test times would be available without any interference
with the time-limited operation of the existing accelerators. Therefore, CRYRING could operate
during the long shutdown period of about 18 months expected around the year 2015 and required
for
• linking the proton linac building to the injection channel TK of SIS18,
• modification of the extraction channel of SIS18,
• installation of the first part of the beam transport from SIS18 to SIS100, and
• major upgrade work on the main control room.
According to these considerations CRYRING would be an excellent, if not indispensable test
bench for many important developments and technologies for FAIR. Its relevance for the success
of the FAIR project with respect to time schedule and quality of operation is briefly discussed
in the following.
5.2
Accelerator Controls
Though CRYRING is not part of the FAIR modularized start version an installation at ESR
would provide excellent possibilities for the controls and other technical departments to implement, test, deploy and evaluate the operational experience for improvements of the technical
systems for FAIR. While it was always foreseen to implement FAIR control system solutions
with the existing GSI machines (SIS18, ESR), CRYRING would provide even better conditions
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Chapter 5. CRYRING as Test Bench for FAIR
for following reasons:
• A new stack of control system solutions for FAIR can be implemented and tested without
ensuring full compatibility and coherency with the existing control system at any time
during development. Some of the new control system design principles for FAIR are
fundamentally different from the present GSI system (e.g. new beam and cycle concept,
replacement of the Virtual Accelerator concept by a more general and flexible one). With
CRYRING, these new solutions can be tested in an almost isolated environment in a system
comprising almost all kinds of accelerator systems (ion source, linear accelerator, beam
lines, synchrotron and storage ring) and without the constraints and having to reimplement
specific GSI functionality of the existing system (e.g. therapy mode, equipment status
concept, etc.).
• CRYRING as a stand-alone machine can provide more machine development time for control system and equipment tests with much less organizational overhead than at UNILAC,
SIS, and ESR.
• The present GSI accelerator chain will experience a strongly reduced operation time in the
coming years (e.g. 3–4 months of operation per year only) and machine time for control
system tests will be quite limited. Machine operation times will be highly dedicated to
machine development (MD) activities as well as detector tests for FAIR. Since beam time
will be rare, a very stable and reliable control system is essential. This situation would be
in contradiction with the strategy to implement novel solutions and evaluate them during
longer runs. New solutions cannot provide the same level of robustness and availability
from the beginning on. It is to be expected that failures will occur. The opportunity of
dedicated MD runs at an independent ion beam facility will allow to solve and fix these
rollout problems with a minimal disruption of the precious beam time operation of the
GSI accelerators.
Practically, the strategy of the controls department would be as follows: Many of the control
system solutions needed for CRYRING modification are necessary for FAIR anyway. These are
presently already under development or will be developed in the course of the FAIR project.
These include front-end software equipment classes, generic operator applications, timing system, setting generation software, etc. It is expected that these solutions can be adapted to
CRYRING with only moderate effort. As soon as these solutions are available, they can be
implemented in CRYRING for tests. First activities would be to implement the new control
system environment designed for FAIR in parallel to the CRYRING installation. This environment will be the base for all control system components including those of the beam diagnostics
and available for component and integration tests.
Deeper understanding and more investigation of the present CRYRING control system is
needed to determine which subsystems can be replaced by corresponding FAIR developments.
The following list indicates some examples:
Equipment control for power converters with DC, pulsed and ramped operation. The
FAIR Standard Control Unit SCU with respective Front End Standard Architecture FESA
equipment class developments is the adequate solution. Controller prototypes and engineering samples under development for FAIR can be used.
Timing system would be replaced by the facility-wide new General Machine Timing system.
Modifications to the timing system are needed anyway for beam transfer from ESR. Bunch
to bucket transfer can be implemented and studied for the bunch transfer from SIS18 to
5.3. Beam Diagnostics
17
SIS100 as well as from SIS100 to CR and from CR to HESR for both the proton/antiproton
and the radioactive ion beams.
Setting generation system can be implemented based on the LHC Standard Architecture
LSA framework as an example for a storage ring machine. Tests of the overall storage ring
functionality are possible. Feedback from the users would be highly valuable.
Generic operator control applications under development for FAIR can be reused for FAIR
and valuable operator feedback can be collected and used for improvements. Functions
of remote monitoring and manage control authority domains (main control room, local
control room) can be tested.
Using CRYRING for FAIR development tests will result in reduced commissioning effort
and time for the control system once the FAIR machines need to be commissioned. Moreover,
early testing allows for better and more stable solutions and well tested operator application
programs.
In spite of all these benefits with respect to time and money savings, the control system
solutions for FAIR cannot be implemented and tested in CRYRING without any additional
financial effort and manpower. Technical coordination and necessary software adaptations will
require one fulltime position being assigned to the controls department as early as possible
after a positive management decision to implement CRYRING@ESR. A potential candidate has
already been identified by the Atomic Physics department. For necessary electronic hardware
adaptations, the vocational trainee group (Ausbildungsgruppe) in the controls department as
well as the young technicians having completed their traineeship would be highly interested to
get involved and contribute as well.
Without further investigations and decisions about which subsystems to be replaced by FAIR
solutions, only some rough cost estimates are given in Section 7.2. However, it can be assumed
that for most dedicated hardware components of the control system prototypes and engineering
samples of the FAIR developments could be used at no additional costs.
5.3
Beam Diagnostics
A great part of the work necessary for the CRYRING beam diagnostics could be eased by
applying soft- and hardware techniques foreseen for the FAIR project. All data acquisition
(DAQ) systems, i.e. analog and digital electronics, controllers, digitizers, infrastructure systems
etc., as well as the required software, should unconditionally apply FAIR standards, like FESA
(Front-End Software Architecture) compatibility. Important: DAQ for beam diagnostics is part
of the German in-kind contribution (EoI 13i) for FAIR. The GSI beam diagnostics department
will deliver the complete set of DAQ systems for FAIR and has strong interest in using CRYRING
as a test bench for ongoing hardware and software development projects.
This strategy has the advantages of using CRYRING as a test bench for FAIR and the
reusability of work load. The results obtained during CRYRING commissioning and test runs
will confirm the development concepts and, in this way, improve the preparations for FAIR.
The required manpower and budget for the FAIR-type realization of the CRYRING beam diagnostics will certainly entail additional expenses over a minimum cost/equipment solution (see
Section 7.2) but these can be justified in view of the opportunity for testing new FAIR equipment
under ‘live’ conditions.
18
5.4
Chapter 5. CRYRING as Test Bench for FAIR
UHV Control and Interlock System
The vacuum controls shall be realized as an industrial control system based on Siemens SIMATIC
PLC and a commercial SCADA (Supervisory Control and Data Acquisition) product in connection with the UNICOS (UNified Industrial COntrol System) framework introduced at CERN
for the control of the LHC cryogenics. All devices are connected directly to the PLC and thus
render a very robust solution. It is being developed and delivered as in-kind contribution by the
FAIR member state Slovenia.
It would be favorable to implement and operate a vacuum control installation early before
implementing it in FAIR machines. Evaluation of the complete system and training of the
vacuum group staff would be possible this way. CRYRING provides all necessary vacuum
control aspects, including a bakeout system. The additional cost for the FAIR vacuum controls
is included in Section 7.2.
5.5
Radiation Safety and Access Control System
The CRYRING Cave-B could be removed from existing ZKS system and replaced by an early
installation of the FAIR PSS (personnel safety system). New access gate infrastructure technology and procedures could be tested and optimized in order to implement a well-tested system
later with the FAIR buildings.
5.6
Controls for Technical Infrastructure
The development of instrumentation and control technology will be necessary in order to control
and optimize the supply of various FAIR facilities with electricity, cooling and other auxiliary
media. For instance, the flow reduction of cooling water or cooling air for facilities standing idle
would considerably reduce the required load on the cooling systems. A similar consideration
would probably offer a chance for minimizing the capacity of the electricity installations.
The new control systems could be tested also at the CRYRING at a time when no other
accelerators and experiments are in operation.
5.7
Preparation for FAIR Commissioning
Practical experience from earlier accelerator projects shows that, as far as possible, it must
be avoided to finally test and commission accelerator components and control system at the
same time as the commissioning with ion beams takes place. Precious beam time would be lost
for time consuming trouble shouting especially of controls software and hardware components.
It is without any controversy that, compared to the regular operation, the commissioning of
accelerators usually causes considerably higher demands on both the control system and the
operating staff.
5.7.1
Development and Test of Special Commissioning Software
The presently practiced commissioning concept at the existing accelerator system at GSI requires
to a large extend the intervention of experienced accelerator physicists and engineers. The
approach to optimal machine settings is done by many steps of human interpretation of beam
diagnostic measurements and subsequent commands to the controls software to suitably change
settings. Not only the extremely tight time schedule for the commissioning of the new FAIR
facilities but also the requirements of a highly efficient operation with time sharing between
5.7. Preparation for FAIR Commissioning
19
different ion species and energies for several beam users necessitate the development of a novel
commissioning concept. The required new software should assume the interpretation of beam
diagnostics as well as many of the human interventions. By this way, the commissioning time
would be reduced considerably. For the necessary extensive tests of the new commissioning
concept the stand-alone operation of CRYRING offers ideal conditions, independent of shutdown
times for the existing machines.
5.7.2
Training of Operating Staff
At least of comparable importance as development and test of operating software is the extensive
training of the operating staff with respect to the commissioning phase of FAIR. The standalone operation of CRYRING covers nearly all relevant aspects of an accelerator facility: ion
source, beam transport, linear accelerator, bunch-to-bucket transfer or multiturn injection to a
synchrotron/storage ring, beam acceleration or deceleration in the ring, beam cooling and finally
slow and fast beam extraction. Insofar, CRYRING must be considered an necessary complement
of the FAIR project
20
Chapter 5. CRYRING as Test Bench for FAIR
Chapter 6
Proposed Construction Cycle
6.1
Conditions for the Project Start
For the installation of CRYRING on the GSI site the following conditions must be met:
Formal Agreement upon CRYRING installation at GSI: The construction cycle described in the following presumes that a decision on the installation of CRYRING at GSI will
be available by the end of July 2012.
CRYRING disassembly by end of 2012: The CRYRING has to be disassembled and the
components have to be moved out of the building presently occupied by the ManneSiegbahn Laboratory of the Stockholm University (MSL/SU) by the end of 2012. As
the reinstallation of the ring in the planned FLAIR facility has been defined as a part of
the Swedish in-kind contribution to the FAIR project with a validation of 2 Million Euro,
it has to be decided very speedily, how to proceed with the ring components. Since FLAIR
is not a part of the Modularized Start Version (MSV) of FAIR, a storage concept worked
out by the MSL foresees the storage of the CRYRING components over a period of 10
years in 12 dehumidified containers on a site defined by the FAIR GmbH.
An alternative solution is presented here. It considers the prompt reinstallation and operation of CRYRING at GSI as the experimental device and test facility behind the Experimental Storage Ring ESR. This will allow to realize the science options of FAIR and
FLAIR at a much earlier stage as compared to the realization of the modules 4 and 5 of
the MSV.
Support by MSL/SU: There is strong interest on the Swedish side, i.e. by the present
MSL/SU staff and by atomic and nuclear physics groups, to built up and operate the
CRYRING facility as modified for FAIR and FLAIR physics experiments in the near
future instead. Its long term storage in containers for more then ten years is not recommended. The MSL/SU experts expressed their intent to support the reinstallation as well
as the commissioning of CRYRING at GSI. However, this support will be available only
if the reinstallation and the commissioning could take place within the next two or three
years.
Weak interference with FAIR: The envisaged period for the reinstallation and commissioning of CRYRING at GSI in the years 2013–2014 does not interfere with the necessary work
for FAIR. There is a marginal involvement of the design and planning capacities. For the
installation of the necessary technical systems and the reassembly of the CRYRING the
human resources seem to be available until the first components for FAIR will be delivered
21
22
Chapter 6. Proposed Construction Cycle
in the 2nd half of 2014 and many acceptance tests have to be prepared and performed. At
this time the commissioning of the CRYRING@ESR facility should already be finished and
first experiments could be accomplished by operating the facility under the responsibility
of the Atomic Physics (AP) department.
6.2
CRYRING Disassembly and Transport
According to the LSR-TDR (Danared et al. [23]), the MSL/SU will deliver the following items:
For the Low energy injection beam line
• An ion source platform for singly charged ions, with all power supplies including a 90◦
analysing magnet without power supply.
• Electrostatic quadrupole doublets and triplets with HV-supplies.
• An RFQ accelerator with 108.48 MHz rf-generator including a 108.48 MHz debuncher
cavity without rf-generator.
• Two dipole and nine quadrupole magnets without power supplies.
• All necessary beam diagnostics (Faraday cups and luminescent screens).
• All vacuum chambers and pumps.
• All mechanical supports.
For CRYRING as modified for FAIR and FLAIR
• Ring magnets: dipole, quadrupole, sextupole, correction magnets with all power converters
• Fast and slow beam injection and extraction systems consisting of two septum magnets,
two fast kicker magnets, a fourfold electrostatic bumper system for multiturn injection,
and an electrostatic septum for slow extraction together with all necessary power supplies
except that for the injection septum magnet. The latter must be equipped with a pulsed
current supply, if the magnetic rigidity of the injected ion beam is increased from 0.8 Tm
to 1.4 Tm, as desirable for the injection of the ESR beam.
• Acceleration system: drift tube and wide band rf-generator for a ramp rate of 1 T/s.
• Electron cooler with all power supplies.
• UHV components: vacuum chambers, valves, NEG and ion pumps, baking jackets, including replacement of old ones using ceramic paper. Ion pumps need to be equipped with
new power supplies.
• Beam diagnostics (faraday cups, fluorescent screens, electrostatic pick-ups, Schottky pickup, ac and dc beam current transformers, beam-profile monitors).
• Cables as far as dismantling and transport are economically favorable.
• All mechanical supports.
MSL/SU has incurred also the liability for organizing and financing the disassembly and
appropriate transport of all equipment to GSI. However, the participation by GSI staff members
allocated for the later reinstallation seems to be reasonable. They could help to conserve UHV
cleanliness during disassembly, to suitably mark items for later identification, and to protect
sensitive parts from damage during transport.
The CRYRING shall not be decomposed into small single components. Complete subsections
(straight sections between bending magnets) of the ring could be transported after removal of
cables and pipes. In this way, considerable re-assembly work time cost would be saved. In
addition, in order to minimize the reinstallation cost, the technical infrastructure might be
reused to a large extent. Cables between power converters and magnets, distribution lines and
local connections for cooling water and pressurized air, shall be disassembled and transported
in an appropriate way.
6.3. Preparation of the CRYRING Cave at GSI
6.3
23
Preparation of the CRYRING Cave at GSI
The reinstallation of CRYRING is proposed behind the ESR with regard to the least possible
interference with presently operating beam lines and experiments. In addition, the most southern
part of the Target Hall will be the ideal location for the ring, when SIS18 and beam lines are
shut down for a longer period in 2015 (at least for 1.5 years) in order to improve the extraction
channel of SIS18 and construct the first part of the beam line to SIS100.
Before modifying Cave B for the installation of CRYRING, the FOPI detector and the
last part of the beam line have to be disassembled and cabling and piping for FOPI must be
removed. For the heavy FOPI solenoid a suitable storage position must be found until its
future employment is decided. Six air conditioned containers, in which detector electronics and
experiment control of FOPI are installed, have to be removed to make room for the extended
area of the nearly square CRYRING cave.
Though the CRYRING will be operated with low intensity beams and generally at low, subthreshold ion energies, radiation shielding by means of concrete walls and covers is necessary.
Regarding the maximum magnetic rigidity of 1.44 Tm, the energies for protons and light ions
would be high enough for nuclear reactions with the implication of neutron production. For
the sufficient concrete shield thickness of 0.8 m the extended CRYRING cave can be completely
built by using supernumerous concrete wall and cover modules of Cave B, where the walls had
to have a thickness of 2.4 m and the covers a thickness of 1.6 m, both consisting of 0.8 m thick
modules.
The ground floor of the extended CRYRING cave is shown in Figure 6.1 together with
CRYRING and injection beam lines. It can be seen that the injection beam line from the ESR
requires a new breakthrough in the northern concrete wall. The cave offers enough space to
install the shortened low energy injector beam line completely inside the cave.
The maximum permitted surface load of 500 kg/m2 of the 0.8 m thick concrete cover allows
for arranging all necessary power supplies and electronics on the cave top. Three air conditioned
containers will accommodate the sensitive accelerator and experiment electronics and a local
control room (see Figure 6.2).
6.4
6.4.1
Preparation of the Technical Infrastructure
Access Control
The controlled access to Cave B can be employed with minor modifications for the new CRYRING cave. It is desirable if the access control could be switched to a local controlling mode
when the CRYRING is operated as a stand-alone system. Maintaining the ion source and in-ring
experiments would be much easier and less time consuming.
Compared to the former safety concept, the new cave will require an additional emergency
exit on the eastern side of the cave opposite to the normal access.
6.4.2
Cooling Water
Fortunately the required flux of cooling water does not exceed the capacity of the existing
cooling system. For the connection to the CRYRING and the water-cooled power converters
and containers on the upper floor new pipes have to be installed. It may be possible to reuse
the main ring pipe line and the connection to the components.
24
6.4.3
Chapter 6. Proposed Construction Cycle
Electricity
The extension area of the new cave requires the installation of additional lighting. It would
be worthwhile to increase the brightness in the cave by means of coating the rough concrete
surface with white paint. This would also improve the cleanliness in the cave with respect to
the requirements during the opening and assembly of UHV components.
The mains voltage distribution and 3-phase line connectors have to be installed along ring
and beam lines. The total power loss of the installed heat jackets for the UHV baking system
would require 210 kW. However, baking will be done partially, i.e. sector by sector. Therefore
a line connection for a maximum consumption of about 100 kW in the cave will be sufficient.
6.4.4
Others
The technical infrastructure of Cave B can be almost unchanged from its present configuration.
The walls, where air conditioning and electric lighting are mounted, will not be dismantled.
The same applies for the walls bearing the runways for two cranes, which are required for the
transport of heavy loads inside the cave.
The connection to the pressurized air and dry nitrogen systems is already available in the
existing Cave B. The distribution in the new cave is only a small fraction of installation cost
and activities.
The planning of a false floor for the installation of the power converters will be done as
soon as a detailed arrangement of the supplies has been worked out. It has to be investigated,
whether an impounding basin for the cooling water will be necessary or not. The same is the
case concerning the required impounding basin for the oil-filled transformers. Their position,
inside or outside the Target Hall, on the upper or the ground floor, will be decided after working
out the arrangement of all supplies.
6.5
Fast ESR Beam Ejection and Transport to CRYRING
The CRYRING can be supplied with decelerated ions from the ESR. The option of decelerating
ions to 4 MeV/u is routinely used in combination with the HITRAP decelerator which is designed
for an injection energy of 4 MeV/u. The ESR cycle has been optimized for this extraction energy.
As the operation of the ESR is flexible the beam can be decelerated to other energies as well.
The beams which are available are highly charged stable ions, but also rare isotope beams
from the fragment separator FRS can be injected and decelerated. An injection energy into
the ESR of 400 MeV/u is favorably chosen in order to profit from the availability of stochastic
cooling which is optimized for this energy. At this energy for all ions stripping to the bare
charge state is achieved with high efficiency. For lower charge states the injection energy can be
reduced. Cooling after injection at lower energies can be performed by electron cooling which
is slower for hot beams, but has also been used in many ESR experiments and which results in
even better condition for deceleration. The injection energy of 400 MeV/u is sufficiently high
for the production and storage of rare isotope beams which need an even higher primary beam
energy due to the use of thick production targets and the energy loss in the target.
Independent of the injection energy the standard ESR deceleration cycle employs electron
cooling at an intermediate level of 30 MeV/u. The cooling provides best conditions for efficient
deceleration and the intermediate flat top in the magnetic cycle is used for changing the rf
frequency from harmonic number h = 2 to h = 4. This change is necessary due to the limited
frequency tuning range of the rf system. The deceleration to 4 MeV/u is done with harmonic
number h = 4. At 4 MeV/u electron cooling is applied again in order cool the beam to small
emittance and momentum spread which eases the transfer to a subsequent accelerator.
6.6. Completion of the CRYRING Components
25
A serious limitation for the preparations at the low energy originates from the short lifetime
of highly charged ions which is caused by electron capture from the residual gas atoms. Lifetimes
of a few seconds were observed for beams of highly charged ions at 4 MeV/u.
The fast extraction from the ESR with a kicker magnet can be applied to a coasting or a
bunched beam. The coasting beam results in losses determined by the rise time and the available
flat top time of the kicker pulse. For HITRAP operation the second ESR cavity was modified
so that it can be tuned to the revolution frequency of the circulating decelerated ions. Thus a
single bunch is formed which can be significantly shorter than the ESR ring circumference. The
bunching with h = 1 allows extraction from the ESR and injection into CRYRING with highest
efficiency. The fast extraction, either of coasting or of a bunched beam, which was developed
for HITRAP, would also be available for the transfer of decelerated ions to the CRYRING.
The intensity of the cooled beam at low energy is limited by the space charge tune shift
which is more pronounced for a bunched beam. On the other hand, as the space charge limit
is virtually independent of the accelerator, it also applies to the CRYRING and therefore sets
the limit for achievable beam intensities. Measurements of the coasting (unbunched) beam at
4 MeV/u showed a momentum spread of ∆p/p about 10−4 or better. Even with moderate
bunching transverse emittances x,y smaller than or equal to 10−3 mm mrad were found.
If the CRYRING is ready to accept particles at higher energy, the deceleration in the ESR can
end at any energy between the intermediate energy of 30 MeV/u and the energy of 4 MeV/u. This
will reduce losses in the ESR and shift the lifetime problem by electron capture from the residual
gas to the CRYRING which is expected to perform even better due to its lower vacuum pressure.
The transfer energy is not limited by the ESR performance, but by the bending power of the
CRYRING magnets and the parameters of the CRYRING injection kicker. The parameters of
this system are still under discussion as it is currently being manufactured. Operation with
4 MeV/u beams is in full accordance with the present specification, but operation up to the
maximum bending power of the CRYRING which for bare ions corresponds to roughly 14 MeV/u
is expected to work with the present kicker design.
The ESR has already now achieved all parameters which are required to serve as a decelerator
of heavy ions for CRYRING. The only modification which is needed is the installation of an
additional fast kicker system. The CRYRING installation is planned south of the ESR, therefore
the beam must be extracted towards the SIS Target Hall. The existing fast kicker cannot be
used for extraction towards the south. A new kicker must be installed in the northern arc of the
ESR. A position close to the existing magnetic and electrostatic septum would be favorable in
order to adopt the same ion optics and extraction concept which is used for the slow extraction
implemented in the ESR. The electronics and the power part for this new kicker can be salvaged
from a previous diagnostics kicker which was dismounted a few years ago. Therefore only the
kicker magnet and a new or modified vacuum chamber are needed.
As the ion optical mode of the ESR would be the same as for slow extraction the matching
of the beamline for the transport of the beam to CRYRING could be copied from the slow
extraction mode. Slow extraction from the ESR was used down to energies of 11.9 MeV/u
and the magnetic system was designed for decelerated beams. Consequently no difficulties in
transporting low energy beam from the ESR to CRYRING are expected.
6.6
6.6.1
Completion of the CRYRING Components
Magnets
The new beam line from ESR can be assembled from existing magnets available at GSI:
• Two 22.5◦ bending magnets,
26
Chapter 6. Proposed Construction Cycle
• Six quadrupole magnets (types SQ010-SQ030), and
• Two H/V steering magnets.
All magnets are components of the beam distribution system behind the UNILAC designed for
a maximum magnetic rigidity of 4.4 Tm. Hence they are well suited for the maximum value of
1.44 Tm rigidity of the beam from the ESR. It should be noted that the power consumption will
be below 10% of the nominal values and the required amount of cooling water is correspondingly
small.
6.6.2
Power Converters
Power converters will have to be made available for all magnets of the two injection beam lines.
Fortunately all required supplies are available at GSI, except a pulsed 2940 A supply for the
injection septum magnet which has to be purchased from an industrial company. It is necessary
for the injection of ions from the ESR at the maximum magnetic rigidity of 1.4 Tm.
The power supplies for all ring and electron cooler magnets shall be reinstalled on the concrete
cover of the new cave. The peak power of about 2.6 MVA for the operation of CRYRING with a
ramp rate of 7 T/s requires a corresponding intermediate 20/10.5 kV transformer, if the existing
oil-filled 10.5 kV/880–400 V transformer for silicon controlled rectifiers SCR application is used.
The alternative solution of a new 20 kV/880–400 V dry transformer for SCR will be investigated
later.
6.6.3
Beam Diagnostics
From the discussion with MSL colleagues it is clear that the beam diagnostic equipment will
not be ready for use ‘out of the box’, because of several reasons.
• Data acquisition systems were in most cases purpose-built by MSL experts and GSI will
not be able to service and maintain the devices.
• Often the applied techniques are somewhat outdated (e.g. PC interfacing for residual gas
ionization profile monitor) and will have to be renewed for future usability.
• In general, the degree of control system integration is relatively low: only Faraday-cups
and scintillating screens have interfaces to the control system at MSL.
As a consequence, more or less the complete data acquisition part of the diagnostic systems has
to be renewed, whereas the detectors and mechanics would remain unchanged wherever possible.
Additionally, it is emphasized that no spare parts exist for the diagnostic components, which
introduces some risk for future operation of the devices.
It has to be mentioned that the replacement of the existing data acquisition (DAQ) systems
with state-of-the-art techniques will consume the major part of the man power required for the
commissioning of CRYRING beam diagnostics at GSI. The renewal of the DAQ is a project
in its own and requires manpower for technical coordination, for adaptations of the existing
hardware (digital and analog electronics), as well as for programming DAQ software.
6.6.4
Radio-Frequency Components
108.48 MHz RFQ and debuncher The 108.48 MHz end stage for the RFQ accelerator requires
a new 2–5 kW solid state driver amplifier. The same type can be applied also to operate the
debuncher cavity to reduce the momentum spread of the 300 keV/u RFQ beam from ±1% to
±0.5% in order to increase the efficiency of multiturn injection to CRYRING.
Wideband drift tube The present wideband generator for the drift tube accelerating gap of
CRYRING allows a dipole ramp rate of 1 T/s for acceleration or deceleration in the frequency
6.6. Completion of the CRYRING Components
27
range of 40 kHz to 2.4 MHz. With a sinusoidal waveform the 200 W generator produces 280
Vp−p into 50 Ω which a balloon transformer multiplies by 4, giving 1 kVp−p at the drift tube
gaps. For higher ramping rates (4 T/s or 7 T/s) the gap voltage has to be increased proportional
to dB/dt and the required RF power proportional to the square of dB/dt.
6.6.5
UHV
For the remote control of vacuum sections and bakeout systems the existing MSL hardware can
be adapted after some modification to the present GSI vacuum and interlock control. The cost
for the control unit planned for FAIR is included in Section 7.2.
CRYRING and Low-Energy Beam Line Although all vacuum chambers, beam pipes and
pumps will be delivered by MSL, the material for the reassembly must be purchased: CF
and Helicoflex gaskets, temperature resistant bolts and nuts, new non evaporable getter (NEG)
material for 40 pumping units, cables etc. In addition, the HV supplies for 6–10 Varian ion
pumps have to be replaced by new units.
Mechanical pumps will be installed permanently only in the LE beam line near the ion source.
The CRYRING itself will be evacuated by means of mobile turbopump units. We expect that a
fraction of about 10% of the baking jackets will have to be replaced because of damage during
disassembly and transport.
Beam Line from ESR The missing vacuum sections of the beam line from the ESR have to be
purchased. Only the magnets from the GSI pool are equipped with vacuum chambers (dipole
magnets) or pipes (quadrupole and steering magnets). All other parts, valves, chambers for
pumping and beam diagnostics, pipes with compensators, measuring systems and ion pumps
have to be purchased if not available from the GSI pool.
6.6.6
CRYRING Control System
The present CRYRING accelerator control system is in almost all aspects very different from
the existing GSI control system as well as the control system under development for FAIR. As it
is, it cannot be coherently integrated in the existing GSI control system framework. Taking into
account that GSI fully focuses its activities and resources on the FAIR project, a comprehensive
replacement of the CRYRING control system within the proposed time schedule (setting up the
machine at ESR in the course of the year 2013) is unrealistic. Moreover, no technical support
and maintenance to the original CRYRING control system can be provided by the Accelerator
Controls Department (BEL).
Consequently, this report proposes to initially set up and recommission CRYRING at GSI
with its original control system with support by CRYRING experts from Sweden. However, a
partial or full replacement of the control system after initial recommissioning is possible and
would even provide excellent test opportunities for FAIR (see Chapter 5).
Considering the installation of CRYRING at GSI, it was discussed and agreed with the
technical experts, that it is not reasonable to move the present general IT infrastructure of
the CRYRING control system (servers, active network equipment, and control room operator
stations) to GSI. Instead, a new system environment shall be provided and installed by the GSI
Controls department on which the CRYRING control system can be installed and configured
by CRYRING experts from Sweden.
28
6.7
6.7.1
Chapter 6. Proposed Construction Cycle
Assembly of CRYRING and Injection Beam Lines
Preparation of Magnetic Components: Fiducialization
As network measurements and final alignment are based on using Laser Trackers and Digital
Levels about 55 magnetic components of the CRYRING and two injection beam lines have to be
fiducialized before assembly. Fiducialization means that the magnetic axes, planes and effective
centres of dipole, quadrupole or sextupole magnets have to be transferred to mechanical marks
suitable for the final alignment during the assembly of beam lines and ring. As the alignment of
12 quadrupole magnets in the injection beam lines will be carried out by telescope, fiducialization
of these components is not necessary and a 3D-determination of the actual condition w.r.t. the
global coordinate system will not be possible.
6.7.2
Procurement of Mechanical Parts
The procurement of about 200 additional mechanical supports is necessary for lifting the low
energy injection beam line and the present beam axis of CRYRING from 1.5 m to 2.0 m which
is the nominal height for ion beams in ESR and in the Target Hall.
The material for the supports of the 20 m long new beam line from the high energy beam
transport to the CRYRING is available from the pool of dismantled systems.
6.7.3
Assembly
Survey Before starting the mechanical assembly the positions of all bending magnets (beam
lines and CRYRING) have to be surveyed precisely. Position marks on the ground floor with an
accuracy of ±0.5 mm will help to achieve a rather good positioning during the assembly work
without the presence of the survey people.
Assembly of CRYRING The assembly of the ring will be performed sector by sector. By
this way assembled sectors can already be connected to power supplies and water cooling while
others are still being mechanically assembled. Fine alignment of the ring can be done by means
of laser tracking simultaneously to the mechanical assembly of the injection beam lines.
Assembly of Injection Beam Lines The alignment of the beam lines will be done by applying
conventional methods. Therefore three pillars with bearings for telescopes have to be surveyed in
advance. Targets marking the axes of quadrupoles will allow fine adjustments to about ±0.5 mm
accuracy. Suitable marks on the luminescent screens, applied for the determination of the ion
beam axis, can be adjusted by this method to similar accuracy.
6.7. Assembly of CRYRING and Injection Beam Lines
29
Figure 6.1. Detailed view of proposed modification to Cave B with the installation of CRYRING@ESR.
30
Chapter 6. Proposed Construction Cycle
Figure 6.2. Arrangement of power supplies and other technical installations for CRYRING on top
of the modified Cave B roof.
Chapter 7
Project Steering
7.1
Time Schedule
The proposed time schedule of the CRYRING@ESR project is shown in Figure 7.1. The rather
tight schedule is associated to the boundary conditions at the Manne-Siegbahn-Laboratory and
at GSI/FAIR described in Section 6.1 which are repeated here once more:
• The disassembly and removal of CRYRING has to be finished around the end of 2012.
• The absolutely necessary technical support by experienced MSL staff members during
reassembly and commissioning of the modified CRYRING at GSI will be available only
during the coming two or three years.
• The support by GSI staff from technical divisions (BES and GA) will be disposable only
until middle of 2014.
2012
5
6
7
8
2013
9 10 11 12 1
2
3
4
5
6
7
2014
8
9 10 11 12 1
2
3
4
5
6
CRYRING@ESR (a study goup report)
GSI board (May/June)
FAIR board
(June)
FAIR council (Dec. 2nd)
Clearing of Cave B area
Disassembly of CRYRING at MSL
Construction of CRYRING cave
Transport of CRYRING to GSI
Fast beam ejection at ESR
Reassembly at ESR
Commissioning with RFQ injector
Commissioning with ESR beam
First experiments
Figure 7.1. Proposed time schedule for CRYRING@ESR under the boundary conditions described
in Section 6.1
In order to meet the described conditions the project should be started without any delay
within the coming 2 months. The most urgent decisions have to be made concerning both the
dismantling of Cave B and the disassembly of the FOPI-detector, i.e. concerning the clearing
of the Cave B area. A detailed MS project plan for disassembling CRYRING at MSL and
31
32
Chapter 7. Project Steering
reassembling it in the Target Hall at GSI has been worked out already by the BES division,
responsible for all mechanical work packages. The plan supposes that the start of the activities
takes place in August 2012.
7.2
Cost and Manpower Requirements
The cost and man power requirements for the realization of CRYRING@ESR were analyzed
in detail. We have completed our analysis for two scenarios, a minimal solution and a FAIR
compatible setup. A minimal solution adapts the ring mostly as it is to the GSI infrastructure.
The cost estimate for the minimal solution is 1 190 k¤ and includes all work performed by
external companies. Moreover, 290 man weeks for the installation need to be provided by GSI,
i.e. its infrastructure divisions (about 7–8 man years). It shall be noted, that this estimate
does not yet include the costs for installation and commissioning of the main ring magnet power
supplies; there, negotiations with external companies are still ongoing.
The FAIR compatible solution will require additional expenses of 717 k¤ and additional 197
man weeks. These additional expenses should be covered by the FAIR budget (for test benches
and hardware commissioning).
The majority of cost estimates are based on careful calculations by experts from technical
divisions. Some items are still rough estimates, some may be too high and less expensive
alternatives are under investigation by the EET division.
7.3
Project Structure: Installation and Operation
For the installation of CRYRING at the ESR and finally for its operation, a dedicated project
team is required. This team will be responsible for the organization, coordination, and physics
performance of CRYRING@ESR (see
Figure 7.2).
During
Organization
Project
Phasethe installation phase, it needs to
Project Coordinator
Ion Optics&
Electron
Cooling
physicist**
Ion Source &
RFQ Injector
Mechanics &
UHV
Beam
Diagnostics &
RF
physicist
engineer
physicist
Controls &
Power
Supplies
physicist or
engineer
Cave
Infrastructure
& Safety
physicist or
engineer
** also deputy project coordinator
Figure
7.2. Organisation chart for the project phase of CRYRING@ESR. (** also deputy project
coordinator).
act in close cooperation with the teams of GSI infrastructure and will coordinate in addition
the support by external groups, such as by the colleagues from Sweden. After the building up
phase, the project team will change its profile and takes over the responsibility for operation
(Figure 7.3). Basically, the group members will nearly remain the same but their tasks will
be directed towards operation, maintenance, and the demands of the FAIR project (test of
novel beam diagnostics, controls etc.). Members of the atomic physics division will act as the
core of the project team. Most of them are already involved into the HITRAP project and its
commissioning. Since from physical and technical point of view HITRAP and CRYRING are
closely entangled (both HITRAP and CRYRING are the central facilities within the FLAIR
building), the merging of both projects appears to be evident. The time and resource planning
for HITRAP need to be adjusted accordingly. The assignment of personnel as well as the use of
7.4. Possible Sources of Funding
33
Organization Commissioning & Operation
Coordinator Operating &
Experiments
Ion Optics&
Electron
Cooling
physicist**
Ion Source &
RFQ Injector
Mechanics &
UHV
Beam
Diagnostics &
RF
physicist
engineer
physicist
Controls &
Power
Supplies
physicist or
engineer
Cave
Infrastructure
& Safety
physicist or
engineer
** also deputy project coordinator
Figure
7.3. Organisation chart for commissioning and operation of CRYRING@ESR. (** also
deputy operating & experiment coordinator)
available financial resources has to be redistributed in order to enable HITRAP and CRYRING
but with the priority to accomplish the installation of CRYRING before mid of 2014.
7.4
Possible Sources of Funding
In the following we list possible sources for funding of the CRYRING@ESR project. Once the
project has been accepted, further sources of support will be investigated.
• Merging of the HITRAP and the CRYRING project: Resources for investment and consumables will be redistributed accordingly. Man power for the project team will be provided by the atomic physics division.
• Collaboration agreement between KVI and GSI.
• Collaboration agreement between MPIK Heidelberg and GSI.
• Offer by the University of Stockholm to support the installation of CRYRING by experienced personnel (in total up to two FTEs).
• Stockholm University has recently offered an advanced internal gas target system for CRYRING experiments.
• A team of Atomic Physicists from Chalmers University of Technology, Gothenburg and
Stockholm University, as well as Nuclear Physicists from Chalmers and Lund University
and Accelerator Physicists from Stockholm University and ESS, Lund, are preparing an
application to the Knut & Alice Wallenberg Foundation for travel costs and stationing of
personnel for extended periods of time at GSI/FAIR.
• Application sent to the Council for Research Infrastructures in April 2012 by the board of
SFAIR, the “umbrella organization” of Swedish scientists aiming for using FAIR further
applications such as EU synergy grants.
• Support by the Helmholtz-Institute Jena can be anticipated.
7.5
Swedish contributions to the installation of CRYRING@ESR
The Manne Siegbahn Laboratory (MSL) at the Department of Physics, Stockholm University
will mutatis mutandis fulfill the commitment as described in section 2.4 of the FLAIR LSR
Technical Design Report [23]. In the changed perspective of a fast installation of CRYRING
at ESR this would mean that MSL is responsible for the new hardware and modifications defined in the LSR, disassembling of the CRYRING and the transportation of it to GSI/FAIR in
34
Chapter 7. Project Steering
Darmstadt in the beginning of 2013. It is planned that a small group from GSI will be invited
by MSL to spend some months in Stockholm during the autumn 2012 to participate in the
final disassembly and packing of the CRYRING in order to gain experience about the configuration of CRYRING before the disassembly. This experience would help considerably for an
optimal reassembly of the ring at GSI. It should be remarked that the fact that the CRYRING
is available intact and properly modified according to the requirements defined by the FLAIR
collaboration has been accomplished by a large grant from the Swedish Research Council and by
generous support from Stockholm University, both acknowledging the high scientific potential
of the future use of the CRYRING at GSI/FAIR. The leader of the MSL team is the accelerator
physicist Anders Källberg, who through the years has been responsible for the operation of the
CRYRING at MSL. In addition to the CRYRING hardware described in the TDR, Stockholm
University has recently offered an advanced internal gas target system for CRYRING experiments to be delivered with a ring. This opens new scientific opportunities which have attracted
a substantial interest from physicists planning future experiments at CRYRING@ESR. After
the transportation of CRYRING to Darmstadt, there are hitherto no formal commitments for
a Swedish participation in its installation at the ESR. However Stockholm University offers
that two experienced accelerator physicists, a highly qualified engineer, expert on the CRYRING Control System and a mechanical engineer will spend up to in total two person-years
at GSI/FAIR. Dependent on the success of applications of further financial support from the
Swedish Research Council (application sent to the Council for Research Infrastructures in April
2012 by the board of SFAIR, the “umbrella organization” of Swedish scientists aiming for using FAIR) and the Knut & Alice Wallenberg Foundation (see below), Swedish presence in the
installation and commissioning work might be increased.
7.6
Swedish Participation in Experiments at FAIR: CRYRING@ESR
The new exciting scientific opportunities that can be offered soon with an early installation
of the CRYRING@ESR have stimulated Swedish scientists to plan for experiments at the new
facility. A team of Atomic Physicists from Chalmers University of Technology, Gothenburg and
Stockholm University, as well as Nuclear Physicists from Chalmers and Lund University and
Accelerator Physicists from Stockholm University and ESS, Lund are preparing an application
to the Knut & Alice Wallenberg Foundation for travel costs and stationing of personnel for
extended periods of time at GSI/FAIR. Scientific issues that are planned to be addressed are
within the areas: Atomic-ion collisions, Ion-photon collisions and nuclear and nuclear astrophysics experiments. An important part of the application is also positions for two postdoctoral
researchers, who should work on
1. starting up research development on experiments and detectors with a focus on nuclear
reactions and nuclear astrophysics and
2. ion-optical problems, in particular optimization of the transmission of radioactive beams
into the ESR.
The main applicant, PI, for the application to the Knut & Alice Wallenberg Foundation is
Andreas Heinz, nuclear physicist at Chalmers University of Technology.
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36
BIBLIOGRAPHY
[18]
SPARC. Stored Particles Atomic Research Collaboration. url: http://www.gsi.de/
sparc.
[19]
FLAIR. Facility for Low-energy Antiproton and Ion Research. url: http : / / www .
flairatfair.eu/.
[20]
EXL. EXotic nuclei studied in Light-ion induced reactions. url: http://www.rug.nl/
kvi/Research/hnp/Research/EXL/index.
[21]
ILIMA. Isomeric beams, LIfetimes and MAsses. url: http://www.fair- center.eu/
fair-users/experiments/nustar/experiments/ilima.html.
[22]
ELISe. ELectron-Ion Scattering Experiment. url: http://www.fair-center.eu/fairusers/experiments/nustar/experiments/elise.html.
[23]
H. Danared, G. Andler, M. Björkhage, et al. LSR - Low-energy Storage Ring. Technical Design Report. Version 1.3, May 6th 2011. Manne-Siegbahn Laboratory, Physics
Department, Stockholm University, 2011.
Appendix A
Letters of Support
Letters of Support for CRYRING@ESR were kindly provided by several international research
groups and all storage ring collaborations of the FAIR project and are appended in the following:
• KVI Groningen (pg. 38),
• Institute of Modern Physics, Chinese Academy of Sciences (pg. 39),
• the community of Austrian researchers (pg. 40),
• Swedish FAIR Consortium (FAIR Sweden) (pg. 43).
The storage ring collaborations at FAIR:
• ELectron-Ion Scattering Experiment, ELISe collaboration (pg. 45),
http://www.fair-center.eu/fair-users/experiments/nustar/experiments/elise.
html
• EXotic nuclei studied in Light-ion induced reactions, EXL collaboration (pg. 46),
http://www.rug.nl/kvi/Research/hnp/Research/EXL/index
• Facility for Low-energy Antiproton and Ion Research, FLAIR collaboration (pg. 47),
http://www.flairatfair.eu/
• Isomeric beams, LIfetimes, and MAsses, ILIMA collaboration (pg. 48),
http://www.fair-center.eu/fair-users/experiments/nustar/experiments/ilima.
html
• Stored Particles Atomic Physics Research Collaboration, SPARC collaboration (pg. 50).
http://www.gsi.de/sparc
37
Prof. Dr. Horst Stöcker
GSI Helmholtzzentrum für
Schwerionenforschung GmbH
Planckstr. 1
64291 Darmstadt
Wien, 23.05.2012
Dear Prof. Stöcker, lieber Horst,
Bearbeiter/in / Durchwahl / E-Mail
we, members of the community of Austrian scientists interested
in the research possible at FAIR, want to express our strong
support for the recent initiative of installing the CRYRING accelerator at the ESR storage ring of GSI. This will open up the possibility to explore already now a part of the physics program of
FLAIR with highly charged ions available from ESR and keep
CRYRING in continuous operation until antiproton or higher intensity HCI beams from FAIR become available, for which
CRYRING was originally foreseen. The FOPI experiment existing
in the vicinity of ESR could then potentially be used to explore
hadron physics with stopped antiprotons, which will be a unique
feature of FLAIR.
We think this current initiative will strengthen the interest and
support of the physics communities in FLAIR and will allow a
strong physics program to be carried out until the full FLAIR facility can be realized.
Yours sincerely
Prof. Eberhard Widmann
Director, Stefan Meyer Institute
Page 1 of 3
Prof. Dr. Eberhard Widmann, Director
Eberhard.widmann@oeaw.ac.at
Expression of support for
CRYRING@ESR
Univ.-Prof. Dipl.-Ing.Dr. Gerald BADUREK
Dean of the Faculty of Physics
Vienna University of Technology
Univ.Prof. Dr. Friedrich Aumayr
Institut f. Angewandte Physik
Vienna University of Technology
Univ.Prof. Dipl.-Ing. Dr.techn. Manfried Faber
Atominstitut
Vienna University of Technology
Univ.Prof. Dipl.-Ing. Dr.techn. Helmut Leeb
Atominstitut
Vienna University of Technology
Ass.Prof. Dipl.-Ing. Dr. Erwin Jericha
Atominstitut
Vienna University of Technology
Page 2 of 3
2(2)
timely implementation of major parts of the APPA-FLAIR facility, now in module 4, in
a much earlier stage and could as well serve for research along the scientific lines of
NUSTAR.
The community represented by SFAIR is most supportive to these plans, and have or
are underway to try to secure additional resources for their successful completion.
Several research groups from Swedish universities have declared strong interest in using
the CRYRING/ LSR set-up with beams from the ESR in the first phase for novel
research program. Furthermore, key personnel from MSL will be made available from
Stockholm University to support the mounting and commissioning of CRYRING/ LSR
in the Target Hall at GSI.
We emphasize that SFAIR sees the CRYRING/ LSR project as an important step to
realize the storage ring physics program in a timely manner at FAIR.
Chairperson, SFAIR
c.c. T. Stöhlker, GSI
B. Sharkov, FAIR
G. Rosner, FAIR
Organisations/VATnr:
202100-2932
GSI Helmholtzzentrum für
Schwerionenforschung GmbH
Planckstraße 1
64291 Darmstadt
www.gsi.de
GSI . Planckstraße 1 . 64291 Darmstadt . Deutschland
Nuclear Reactions/Research
Prof. Dr. Thomas Stöhlker
Head of Department:
Prof. Dr. Thomas Aumann
Deputy:
Dr. Haik Simon
Phone +49 6159 71-2887
Fax
+49 6159 71-2809
Mobile +49 1743281519
H.Simon@gsi.de
Subject:
CRYRING project:
Letter of support from the ELISe collaboration
May 20th, 2012
Dear Prof. Dr. Thomas Stöhlker, dear Thomas,
I am writing this letter as the spokesperson of the ELISe collaboration and on behalf
of the collaboration. I would like to express our full support and interest in the activities leading to the storage ring facility ESR and CRYRING@ESR, being initially
coupled to the FRS and potentially later to the Super-FRS.
Since ELISe is not included in the start-version of FAIR, the CRYRING@ESR facility provides excellent opportunities for test experiments and detector developments
for the in-ring instrumentation of the ELISe setup.
We are currently looking also into the opportunities for first installing the eA collider
at the ESR with limited performance, keeping in mind that we’d be such already
competitive with the upcoming SCRIT facility in Japan.
In this context we welcome any activities and plans that allow for a vivid and strong
nuclear physics programme at GSIs storage ring prior to the delayed realization of
the NESR at FAIR. The realization of CRYRING@ESR would set an important corner stone immediately thrilling all experimental communities associated with the
storage ring physics programme at FAIR.
With kind regards,
(Haik Simon)
Geschäftsführung:
Professor Dr. Dr. h.c. Horst Stöcker
Dr. Hartmut Eickhoff
Vorsitzende des Aufsichtsrates:
Dr. Beatrix Vierkorn-Rudolph
Stellvertreter:
Ministerialdirigent Dr. Rolf Bernhardt
Sitz: Darmstadt
Amtsgericht Darmstadt HRB 1528
VAT-ID: DE 111 671 917
Landesbank Hessen/Thüringen
BLZ 500 500 00 . Konto 50 01865 004
IBAN DE56 5005 0000 5001 8650 04
BIC HELA DE FF
Prof. Dr. Horst Stöcker
GSI Helmholtzzentrum für
Schwerionenforschung GmbH
Planckstr. 1
Gespeicherte und gekühlte Ionen
Stored and Cooled Ions
Prof. Dr. Klaus Blaum
Tel: 06221-516 850/1
Fax: 06221-516 852
sekretariat.blaum@mpi-hd.mpg.de
64291 Darmstadt
25. April 2012
Dear Professor Stöcker, lieber Horst,
On behalf of the FLAIR collaboration we would like to express our strong support for the
CRYRING@ESR project, and we appreciate very much the future option of a connection to
the Super-FRS.
Since FLAIR is not included in the start-up version of FAIR, the CRYRING@ESR project
provides excellent possibilities to pursue already some of our planned test experiments and
detector tests, especially in view of the delay in the construction of the New Experimental
Storage Ring (NESR), which is a mandatory ring for FLAIR. CRYRING@ESR will provide
low energetic highly charged heavy ion beams, one of the main experimental programs of
FLAIR, see the LSR-project within FLAIR.
In addition, a continuous running of CRYRING and the installation of HITRAP at its final
position will allow a fast and efficient start of the physics program of FLAIR@FAIR.
In summary, we see the CRYRING@ESR installation as an excellent initiative towards the
low-energetic storage ring projects at FAIR.
With our best regards,
KLAUS BLAUM
Spokesperson of the FLAIR Collaboration
EBERHARD WIDMANN
Co-Spokesperson of the FLAIR Collaboration
Professor H. Stöcker
GSI, Darmstadt
4th May 2012
Dear Professor Stöcker,
On behalf of the ILIMA collaboration, I would like to express strong support for the
CRYRING@ESR project, with the future option of a connection to the Super-FRS.
One of the main facilities for the ILIMA experimental program is the New
Experimental Storage Ring (NESR), which is however outside the start-up version of
FAIR. As has often been stressed, this significantly delays the realisation of the
planned storage-ring experimental programs, and it could also cause irreversible
negative consequences for the associated experimental communities.
A novel possibility is now under consideration. Installation of the CRYRING coupled
to the present ESR will extend the physics capabilities by enabling the production, in
the near future, of highly ionized heavy ions at the lowest kinetic energies. This
project has very high experimental discovery potential, including for ILIMA-related
experiments. For instance, searching for the Nuclear Excitation by Electron Capture
(NEEC) and the Nuclear Excitation by Electron Transition (NEET) phenomena will
become possible. Therefore, we support an early construction of the CRYRING
coupled to the ESR.
It is important to emphasise that there is a future option which foresees the connection
of the present ESR to the Super-FRS. This is extremely attractive for the ILIMA
collaboration. It will enable the possibility of performing ILIMA experiments with
cooled exotic ions in the ESR, with the highest secondary-beam intensities which will
be available from the Super-FRS. This transitional arrangement would enable us to
cover part of the ILIMA experimental program prior to the realisation of the NESR.
Furthermore, the novel detector setups, which are foreseen for the NESR experiments,
can be built and implemented for real physics experiments in the ESR under FAIR
conditions, which will allow us to prepare in the best way for experiments in the
NESR.
Overall, we see the CRYRING@ESR as a very timely and important step towards the
success of the storage-ring scientific program at FAIR.
Yours sincerely,
Phil Walker
Spokesperson for the ILIMA Collaboration
STOCKHOLM UNIVERSITY
Physics Department
Atomic Physics Division
Prof. Dr. Reinhold Schuch
May. 24. 2012
Subject: CRYRING@ESR, Letter of support from the SPARC collaboration
To whom it may concern!
I am writing this letter as spokesperson and on behalf of the SPARC collaboration. I would like
to express our full support in this new FAIR related initiative of installing the CRYRING at the
ESR of GSI. This project is an important and essential step towards the realization of our
challenging anticipated physics progam at FAIR which concentrates on physics with stored and
cooled heavy ions and rare isotopes.
Although the storage ring branch of the FAIR project has an outstanding visibility due to its
expected scientific impact, its major component, the NESR, has been postponed by an
undefined amount of years. The realization of CRYRING at the ESR would compensate already
now to a large extend for this loss and this combination of CRYRING with the ESR would
bring the storage ring physics into Modularized Start Version of FAIR. In particular SPARC but
also all the other collaborations that depend on storage rings would profit tremendously from
this project and will keep them actively involved into FAIR. Finally, the SPARC collaboration
is convinced that the scientific success of the CRYRING project at the ESR will promote the
realization of the NESR and the FLAIR facility at the earliest possible date.
I want to point out also, in view of the scientific merits of this initiative, the SPARC
collaboration would contribute as much as possible to realize this important project.
Yours sincerely
Reinhold Schuch
Spokesperson of the SPARC Collaboration
Division of Atomic Physics Address: Physics Center
FYSIKUM
S-106 91 Stockholm
Stockholm University
Sweden
Telephone:
Nat. 08-55378621
Int. +46-8-55378621
Secr:
E-mail addresses:
+46-8-55378600
schuch@physto.se
Fax +46-8-55378601 http://physto.se