Unique Spectrometer Experiments with the Super

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* Spokesperson: Isao Tanihata - Beijing and Osaka
Co-spokesperson: Hans Geissel – GSI
Chair of Collaboration board: Juha Äystö – Helsinki
Co-chair: Christoph Scheidenberger
FAIR Experiments
CBM
APPA
NUSTAR
PANDA
Günther Rosner
2nd ECE Mtg., Darmstadt, 21/6/13
3
Scientific Program of the Super-FRS Collaboration
Report of the collaboration to the FAIR management
Darmstadt, May 26, 2014
• Take advantage of E>1500 A MeV 238U; cross section and
kinematics.
• High-energy and high-intensity primary and secondary nuclear
beams with energies up to 1,500 A MeV.
• Unique high-energy, high momentum-resolution multiple-stage
spectrometer with large acceptance and flexible ion-optical
settings, including the energy-buncher of the LEB.
• High primary-beam suppression power and high separation
power of nuclides up to Z=92, and fully stripped ions of all
elements.
• Versatile spectrometer modes by different combinations of
separator sections, coupled to advanced tracking (GEM-TPC,
diamond,Si,…)
Super-FRS scheme
Science Topics
Super-FRS for high mass and charge resolution (early stage)
1. Rare isotope yields, ground state properties & limits of nuclei
2. Understanding atomic collisions at relativistic energies
Super-FRS as high-energy and high-resolution spectrometer
3. Spectroscopy of meson-nucleus bound system (mesonic atoms)
4. Exotic hypernuclei and their properties
5. Importance of tensor forces in nuclear structure
6. Delta resonances probing nuclear structure (Benlliure, 2C)
Super-FRS as a multi-stage separator and spectrometer
7. Nuclear radii and momentum distributions
8. In-flight radioactive decays and continuum spectroscopy by
particle emission (Pfützner, 4A & Fomichev. PS1-139)
9. Low-q experiments with an active target
10. Reaction studies and synthesis of isotopes with low-energy RIB
Search for new isotopes and the limits of bound nuclei
produced in fission and fragmentation.
Take advantage of E>500A MeV 238U or other beams. Many new
isotopes to be produced in fission, transfer and fragmentation.
Part of commissioning phase (performance, ion optics, tracking,..)
The determinations of production cross sections of unstable nuclei
are imperative for entire Super-FRS operation.
Stopped beam physics (CGC & MRTOF).
Key region for
Super-FRS
J. Kurcewicz et al. Phys.Lett. B 717,371(2012)
T. Kurtukian-Neito et al. Phys. Rev. C 89, 024616 (2014)
Exotic (n-rich) hypernuclei and their properties
Production of hypernuclei at high-energy (>1.2A GeV) heavy-ions
peripheral collision is expected to have large cross sections.
The method is also suitable for determination of lifetimes of
hypernuclei via weak decay channel (Λfree  pp- or np0 , t0.26 ns)
(Lorentz factor on lifetime !)
Strangeness sector of nuclear chart
Pilot experiment at FRS (HypHI)
shows evidences of 3ΛΗ, 4ΛΗ, 3Λn
C. Rappold et al Phys. Rev. C 88(2013)041001
A. Botvina et al Phys Rev C 88(2013)054605
The lifetimes have also been
determined.
Higher mass resolution of Super-FRS
will help for identifications.
Delta resonances probing nuclear structure
(Benlliure, session 2C)
Charge changing reactions with high-energy heavy ions provide
unique possibilities to study baryon resonances, including Δresonances, in exotic nuclei (DS=1, DI=1 excitations).
So far Δ-resonances in nuclei have been studied exclusively in
stable or near stable nuclei
Studying
112
63
112
Sn( Cu,X) Sb
Δ(1232)
In-medium properties of baryon
resonance in isospin asymmetric
nuclear matter
Gamow-Teller transition strength
Radial distribution of neutrons and
protons
Nuclear matrix elements for
inelastic neutrino interactions
Energy loss spectrum of 112Sb
Low-energy reaction studies with RiBs
Will be done at Low-Energy Beam line, employing the energy
buncher.
Will challenge at and above Coulomb-barrier energies a new
field for reaction studies.
Will contribute to a better understanding of deep inelastic,
fusion-fission and complete fusion reactions.
Potentially serves for the extension of the nuclear chart to
regions not accessible in fusion reactions with stable beams
nor in fragmentation reactions.
Conclusions
 The scientific program presented is largely unique or
complementary within the NUSTAR collaboration.
 It is unique in the world when compared with the goals of
other next-generation exotic nuclear beam facilities.
 It is in line with the scientific goals of FAIR and with the
proposed scope of the Modularized Start Version.
 The collaboration is open to, and exploits synergies with the
scientific and technical programs of the other FAIR
collaborations, in particular with APPA, CBM and PANDA.
List of topic conveners for Super-FRS Physics case
• Rare isotope search experiments (Pietri, Jokinen, Plaß et al.)
• Atomic collision experiments (Purushothaman, Geissel et al.)
• Mesonic atoms and in-medium effects (Itahashi, Weick et al.)
• Exotic hypernuclei and their properties (Saito, Nociforo et al.)
• Exploration of tensor force (Ong,Terashima, Toki, et al.)
• Delta resonances probing nuclear structure (Benlliure, Lenske et al.)
• Nuclear radii and momentum distributions (Kanungo, Prochazka et al.)
• Exotic radioactivity modes (Fomichev, Pfützner, Mukha et al.)
• Low-q experiments with Active Target (Egelhof, Kalantar et al.)
• Low energy reactions (Heinz, Winfield et al.)
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