1 / 12

The Equation of State of Asymmetric Matter

Phys. Rev. C 86, 015803 (2012). The Equation of State of Asymmetric Matter. E/A ( ,  ) = E/A ( ,0) +  2 S()  = ( n -  p )/ ( n +  p ) = (N-Z)/A1. ?. ?. ?. ?. B.A. Brown,PRL85(2000)5296 Tsang et al,PRL102,122701(2009). Tsang et al., PRC 86, 015803 (2012 ).

macy
Download Presentation

The Equation of State of Asymmetric Matter

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Phys. Rev. C 86, 015803 (2012) The Equation of State of Asymmetric Matter E/A (, ) = E/A (,0) + 2S()  = (n- p)/ (n+ p) = (N-Z)/A1 ? ? ? ? B.A. Brown,PRL85(2000)5296 Tsang et al,PRL102,122701(2009) • Tsang et al., PRC 86, 015803 (2012) At r<r0 density, consistent constraints have been obtained from different experiments: Heavy Ion Collisions (HIC), Giant Dipole Resonances, Isobaric Analog States (IAS), Finite Range Droplet model (FRDM), Pygmy Dipole Resonances (PDR), Proton elastic scattering on Pb, and neutron star (n-star) radius. • Future Directions • EoS of asymmetric matter at high density using heavy ion collisions with rare isotope beams at high incident energy.

  2. Heavy Ion Collisions at high density with RIB E/A (, ) = E/A (,0) + 2S()  = (n- p)/ (n+ p) = (N-Z)/A1 ? ? ? ? ? ? ? ? B. Liu et al. PRC 65(2002)045201 B.A. Brown,PRL85(2000)5296 Tsang et al,PRL102,122701(2009) At r<r0 density, consistent constraints Effect of mass splitting increase with density and asymmetry Large uncertainties in the symmetry energy high density.

  3. MSU’09- GSI’10 RIBF’12, FRIB’20, KoRIA? FAIR Symmetry Energy Project International collaboration to determine the symmetry energy over a range of density Require: New Detectors (TPC), & theory support

  4. SAMURAI-TPC • Time-projection chamber (TPC) will sit within SAMURAI dipole magnet • Auxiliary detectors for heavy-ions and neutrons, and trigger Nebula (neutron array) SAMURAI-TPC beam Hodoscope SAMURAI dipole magnet and vacuum chamber Drawing courtesy of T. Isobe

  5. Experiments at RIKEN Beams are limited to the primary beams developed at RIKEN and that stable beams are produced as secondary beams. There is no advantage of using stable beams. Furthermore, stable beams are not in the priority list as they are not “unique”. Strategies: Use very neutron rich and n-poor radioactive beams. Propose several reactions to take advantage of the campaign mode. Use Sn targets (available in RIKEN): 112Sn (expensive), 124Sn Primary Beams http://www.nishina.riken.jp/RIBF/BigRIPS/intensity.html 238U, 124Xe, 48Ca, 86Kr (?), 18O, 76Ge(?) TPC considerations: Space-charge effect and track multiplicity considerations favor light Z beams for commissioning

  6. Proposed reactions at RIKEN Proposed Symmetric and Asymmetric systems: Possible beams: 238U fission: 132Sn(10^4.8), 124Sn (10^4.7), 112Sn (10^4.2), 112Ru(4.7) 90Zr(4.8), 96Zr(4.9), 100Zr(5.5), 96Ru(4), 108Ru(5), 197Au(??10^4.2) 48Ca fragmentation: 46Ar (8.24), 34Ar(5.64) or 47K and 37K 86Kr (??) fragmentation: 56Ni (6), 64Ni(8), 70Ni(5.0), 60Zn(5.5), 76Zn(5) Targets available : 112Sn, 124Sn in RIKEN ; 96Zr, 96Ru in GSI Physics goal: Extract Symmetry energy constraints at high density & determination of effective nucleon masses Experimental Observables: p-/ p+ ratios n/p, t/3He ratios p,d,t,3He, 4He flow

  7. 124Sn+124Sn Elab=120 MeV/A b = 1fm • p-/ p+ ratios Bickley et al., private comm. (2009) Jun Hong, private comm. (2012) BUU from: Danielewicz, NPA673, 375 (2000). • p-/p+ ratios show a strong dependence on the symmetry energy at low incident energies and low pion energies. • p-/p+ ratios are lower at high energy because later pion collisions and pion production dilutes the sensitivity to the symmetry energy. • First experiments, use high energy beam to increase pion production.

  8. 124Sn+124Sn Elab=120 MeV/A b = 1fm • p-/ p+ ratios Bickley et al., private comm. (2009) Jun Hong, private comm. (2012) BUU from: Danielewicz, NPA673, 375 (2000). gi gi S(r)=12.5(r/ro)2/3+C(r/ro) • What are the best systems? • Calculations: 132Sn+124Sn; 112Sn+112Sn, 112Sn+112Ru at 300 MeV/u • Experiments: 132, 124, 112Sn + 124,112Sn, 112Sn+112Ru at 300 MeV/u

  9. n/p ratios to probe mn* and mp* and Esym • Previous data (to be published) • 124Sn+124Sn;112Sn+112Sn,E/A=120 MeV • 48Ca+124Sn; 40Ca112Sn,E/A=140 MeV Zhang, private communications Coupland et al, 124Sn+124Sn;112Sn+112Sn,E/A=120 MeV • 132Sn+124Sn; 112Sn+112Sn, 112Sn+112Ru at 200 MeV/u • Will require nebula neutron array

  10. Particles Distributions Detector mismatch θcm 50 MeV protons γ n H neutrons 120 MeV overlap and cut Rejected He Ecm (MeV) Fraction of n decreases and rejected particles increases with incident energy ! Can we detect both n and p with same detector?

  11. Proposed solution with veto arrays Need efficient veto arrays. Use veto+n-wall to identify p New technical development for a large scintillator array to detect p? a pt p d t

  12. Summary Propose experiments Symmetric systems: 132,124,112Sn+124,112Sn; 112Ru+112Sn; E/A=300 MeV, 56-68Ni+56,64Ni; Asymmetric systems: 56-68Ni+124,112Sn; Possible beams:?? Possible targets: 124,112Sn, 58,64Ni, 96Zr, 96Ru, Physics goals: Extract Symmetry energy constraints at high density & determination of effective nucleon masses Experimental Observables: p-/ p+ ratios n/p, t/3He ratios p,d,t,3He, 4He flow Auxiliary detectors Nebula neutron array + scintillation array

More Related