6Li
in ab initio approaches
Youngman Kim
Rare Isotope Science Project (RISP)
Institute for Basic Science (IBS)
In collaboration with:
Ik Jae Shin, RISP, IBS
James Vary, Pieter Maris, Iowa State University
Christian Forssen, Jimmy Rotureau, Chalmers University
PKU-CUSTIPEN workshop (Aug.1-6, 2015@PKU)
Outline
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RISP in Korea
Ab initio NCFC & GSM in very brief
Results (including preliminaries)
Summary
History for RISP
Preliminary Design Study
ISBB plan
2009.01
1st International
Advisory Committee (IAC)
Conceptual Design Study
2011.02
2010.02
2011.07
Rare Isotope Science Project (RISP)
launched
2nd RWAS
2nd TAC
2013.05
2013.06
2012.12
2012.07
2012.06
2nd IAC
KoPAS
(Particle Accelerator School)
2012.05
Baseline
Design Summary
1st RISP Workshop on
Accelerator Systems (RWAS)
1st Technical Advisory Committee (TAC)
Technical Design Report
2013.09
3rd IAC
2st PAC
1st Radiation Safety Review
2014.11
2014.11
1st
2013.10
Program Advisory Committee (PAC)
4
2014.12
Civil Engineering & Construction Project
for RISP launched
2015.05
2011.12
RAON Site
~11 km
Current RISP Office
Area (Lot/Bldg): 952,066 m2 / 130,257 m2
5
RAON Concept
 High intensity RI beams by ISOL & IF
20m
ISOL : direct fission of 238U by 70MeV proton
IF by 200MeV/u, 8.3pμA 238U
ECR-IS (10keV/u, 12 pμA)
LEBT
RFQ (300keV/u, 9.5 pμA)
MEBT
128.5m
 High quality neutron-rich RI beams
132Sn
100m
with up to ~250MeV/u, up to ~108 pps
 More exotic RI beams by ISOL+IF
SCL1 (18.5 MeV/u, 9.5 pμA)
Driver LINAC
Chg. Stripper
375m
70m
SCL2 (200 MeV/u, 8.3 pμA for U+79)
(600MeV, 660 μA for p)
20m
MEBT
250m
RFQ
CB
SCL3
ECR-IS
100m
Post Accelerator
Low Energy Experiments
Nuclear Astrophysics
100m
HRMS
μSR,
IF Target
Bio-medical
RF Cooler
Cyclotron
(p, 70 MeV, 1mA)
High-precision
Mass Measurement
Gas Catcher IF Separator
110m
CB : Charge Breeder
HRMS : High Resolution Mass Separator
7
80m
ISOL
Target
High Energy Experiments
Nuclear Structure/
Symmetry Energy
KOBRA
(KOrea Broad acceptance Recoil spectrometer and Apparatus)
Main facility for nuclear structure and nuclear astrophysics studies
with low-energy stable and rare isotope beams
 Main Research Subject :
1) Nuclear structure of exotic nuclei near the drip lines
2) Astrophysically important nuclear reactions
3) Rare event study - Super Heavy Element (SHE), New isotopes
4) Nuclear physics with polarized beam/target etc
- Main Specification
Stage 1
Wien
filter
Stage 2
Big-bite
Spectrometer
Wien
filter
F3
F1
F2
In-flight separation
or
Beam transport
F0
* Design Concept
1) Two stage
F5
F4
* Associate equipments
FP
Equipments
F0
RI production target,
F3
gas-jet target, gamma-array,
detection system, b-NMR
F5
Focal plane detection system
- RIBs production
via low-E in-flight
method by multi
nucleon trasfer
reaction (ex. 44Ti)
- Stage 1 (F0~F3) :
Production and separation of RIBs
via In-Flight method with high
intensity
SIBs from SCL
Maximum magnetic rigidity (Tm)
~3
Mass resolution (m/Δm) @ stage 1
~700
Dispersion (cm/%) @ stage 1
4.2
Momentum acceptance (%) @ stage 1
±4
Angular acceptance (mrad) @ stage 2
40 (H) and 200 (V)
- Ion optics calculation was done using K-trace code (ray tracing)
- Rotation of ‘stage 2’, variable position of Q-magnets in ‘stage 2’
are under consideration
- Technical design is in progress
- Design of associate equipment
- Stage 2 (F3~F5) :
Big-bite spectrometer with Wien filter
 large acceptance
[Gas-jet target]
[PPAC]
[Gamma array]
LAMPS
(Large Acceptance Multi-Purpose Spectrometer)
Main facility for nuclear matter and nuclear reaction studies
with intermediate energy stable and rare isotope beams
Main Research Subject:
Study of nuclear symmetry energy at supra-saturation density
via heavy-ion collision experiment
L.W. Chen et al.,
PRL 94, 032701 (2005)
Asy-soft
• Beam Energy: up to 250 MeV/u
• Solenoid Spectrometer
- Max. 1T solenoid magnet
- TPC (~ 3 sr acceptance,
charged particle tracking)
- Scintillation counter (trigger & ToF)
- Si-CsI (measure heavy fragment
using E-E method)
• Dipole Spectrometer
- Rotatable dipole magnet and
focal plane detector
(capable to study nuclear reaction)
• Neutron Wall (neutron tracking)
RISP Milestone Schedule
ECR SI Beam
RFQ Beam SCL Demo Beam
SCL SI Beam
IF RI Beam
ISOL SI Beam
Cyclotron
ISOL RI Beam
DAY-1 Experiment
Start Utility Supply
Begin Construction
10
Completion
Ab initio No Core Shell Model
• Ab initio: nuclei from first principles using
fundamental interactions without uncontrolled
approximations.
• No core: all nucleons are active, no inert core.
• Shell model: harmonic oscillator basis
• Point nucleons
Ab initio No Core Gamow Shell Model
Ab initio method and NN interaction
• Unfortunately, the NN interaction at low energies needed for
nuclear physics applications cannot be directly derived from
QCD at the moment
• Ab initio theory requires, of course, a realistic NN interaction
accurately describing NN scattering data and deuteron
properties
• We use NNLOOPT and JISP16 in this study
Ab initio No Core Full Configuration Approach
This method is a version of the ab initio no core shell model (NCSM)
with a few important characteristics:
(1) the use of interactions defined for an infinite Hilbert space,
(2) extrapolating to the continuum limit (infinite matrix limit)
(3) uncertainty estimation for the extrapolation.
Extrapolation methods
P. Maris, J. P. Vary and A. M. Shirokov, Phys. Rev. C 79, 014308 (2009),
C. Forssen, J. P. Vary, E. Caurier and P. Navratil, Phys. Rev. C 77, 024301 (2008),
S. A. Coon, M. I. Avetian, M. K. G. Kruse, U. van Kolck, P. Maris and J. P. Vary, Phys.
Rev. C 86, 054002 (2012),
R. J. Furnstahl, G. Hagen and T. Papenbrock, Phys. Rev. C 86, 031301 (2012),
S. N. More, A. Ekstrm, R. J. Furnstahl, G. Hagen and T. Papenbrock, Phys. Rev. C 87,
044326 (2013),
…
Extrapolating to the infinite matrix limit
“Extrapolations A & B”
P. Maris, J.P. Vary and A.M. Shirokov, Phys. Rev. C79, 014308 (2009)
P. Maris, A.M. Shirokov and J.P. Vary, Phys. Rev. C81, 021301(R) (2010)
Extrapolation A5
Results from Ab initio NCFC
convergence pattern and quantified uncertainties for extrapolation A3 indicate that we are
still far from the converged results for (b).
converge more slowly,
underbound by 1.44 MeV
,
underbound only by 0.46 MeV
1.3 MeV
8.2 eV
24 keV
level ordering is ok with experiments
The slope in HO energy (with increasing Nmax) seems to reflect the experimental trends
Both are within 2% of the experimental value
convergence pattern looks similar to the point proton rms redius
no apparent convergence
reasonable convergence
to a small value, trend seems
ok with the hindered nature
of this transition
reasonable converged, about 3-5% higher than experiments
Results from Ab initio No Core GSM
Energy of the ground state
Energy of a resonance state (2+, 1)
Imaginary part of the energy of (2+, 1) state
Summary
• RAON will start to talk about interesting
physics in several years.
• 6Li is extensively studied in ab initio NCFC.
• We perform initial application of ab initio
GSM to gain estimates of selected
observables in 6Li with a great success.
Thank you for your attention !
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