Symmetry energy from neutron-rich fragments in heavy-ion collisions, and its dependence on incident energy, and impact parameters

  • The yields of fragments produced in the 60Ni+12C reactions at 80 A and 140 A MeV, and with maximum impact parameters of 1.5, 2 and 7.3 fm at 80 A MeV are calculated by the statistical abrasion-ablation model. The yields of fragments are analyzed by the isobaric yield ratio (IYR) method to extract the coefficient of symmetry energy to temperature (asym/T). The incident energy is found to influence asym/T very little. It's found that asym/T of fragments with the same neutron-excess I=N-Z increases when A increases, while asym/T of isobars decreases when A increases. The asym/T of prefragments is rather smaller than that of the final fragments, and the asym/T of fragments in small impact parameters is smaller than that of the larger impact parameters, which both indicate that asym/T decreases when the temperature increases. The choice of the reference IYRs is found to have influence on the extracted asym/T of fragments, especially on the results of the more neutron-rich fragments. The surface-symmetry energy coefficient (bs/T) and the volume-symmetry energy coefficient (bv/T) are also extracted, and the bs/bv is found to coincide with the theoretical results.
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  • [1] Danielewicz P, Lacey R, Lynch W G. Science, 2002, 298: 1592[2] Lattimer J M, Prakash M. Phys. Rep., 2000, 333: 121; Astrophys. J, 2001, 550: 426; Science, 2004, 304: 536[3] Baran V, Colonna M, Greco V et al. Phys. Rep., 2005, 410: 335.[4] Steiner A W, Prakash M, Lattimer J M et al. Phys. Rep., 2005, 411: 325[5] Fuchs C. J. Phys. G: Nucl. Part. Phys., 2008, 35: 014049[6] LI B A, CHEN L W, Ko C M et al. Phys. Rep., 2008, 464: 113[7] MA Y G, Natowitz J B, Wada R et al. Phys. Rev. C, 2005, 71: 054606[8] XU H S, Tsang M B, LIU T X et al. Phys. Rev. Lett., 2000, 85: 716[9] Henzlova D, Botvina A S, Schmidt K H et al. J. Phys. G: Nucl. Part. Phys., 2010, 37: 085010[10] Danagulyan A S, Balabekyan A R, Hovhannisyan G H. Phys. Atomic Nuclei, 2010, 73: 81[11] MA C W, FU Y, FANG D Q et al. Int. J. Mod. Phys. E, 2008, 17: 1669[12] ZHOU P, TIAN W D, MA Y G et al. Phys. Rev. C, 2011, 84: 037605[13] FANG D Q, MA Y G, ZHONG C et al. J. Phys. G: Nucl. Part. Phys., 2007, 34: 2173[14] HUANG M, CHEN Z, Kowalski S et al. Phys. Rev. C, 2010, 81: 044620[15] MA C W, WANG F, MA Y G et al. Phys. Rev. C, 2011, 83: 064620[16] MA C W, PU J, WANG S S, WEI H L. Chin. Phys. Lett., 2012, 29: 062101[17] Minich R W, Agarwal S, Bujak A et al. Phys. Lett. B, 1982, 458: 267c[18] Hirsch A S, Bujak A, Finn J E, Gutay L J, Minich R W, Porile N T, Scharenberg R P, Stringfellow B C, Turkot F. Phys. Rev. C, 1984, 29: 508[19] MA C W, WEI H L, LIU G J et al. J. Phys. G: Nucl. Part. Phys., 2010, 37: 015104[20] WEI H L, MA C W. Acta Phys. Sin., 2010, 59: 5364 (in Chinese)[21] MA C W, WANG S S. Chin. Phys. C (HEP NP), 2011, 35: 1017[22] FANG D Q, SHEN W Q, FENG J et al. Phys. Rev. C, 2000, 61: 044610[23] MA C W, WEI H L, FU Y et al. Phys. Rev. C, 2009, 79: 034606[24] von Weizscker C F. Z. Phys., 1935, 96: 431[25] Bethe H A. Rev. Mod. Phys., 1936, 8: 82[26] Green A E S, Edwards D F. Phys. Rev., 1953, 91: 46[27] Brohm T, Schmidt K H. Nucl. Phys. A, 1994, 569: 821[28] Gaimard J J, Schmidt K H. Nucl. Phys. A, 1991, 531: 709[29] MA C W, WEI H L, LI Y Q. Int. J. Mod. Phys. E, 2010, 19: 1545[30] MA C W, WEI H L, YU M. Phys. Rev. C, 2010, 82: 057602[31] MA C W, FU Y, FANG D Q et al. Chin. Phys. B, 2008, 17: 1216[32] FANG D Q, MA Y G, CAI X Z et al. Phys. Rev. C, 2010, 81: 047603[33] MA C W, WEI H L, WANG J Y et al. Chin. Phys. B, 2009, 18: 4781[34] CAI X Z, FENG J, SHEN W Q et al. Phys. Rev. C, 1998, 58: 572[35] DE J N, Samaddar S K. Phys. Rev. C, 2012, 85: 024310[36] WANG J, Wada R, Keutgen T et al. Phys. Rev. C, 2005, 72: 024603[37] Danielewicz P. Nucl. Phys. A, 2003, 727: 233[38] MEI H, HUANG Y, YAO J M, CHEN H. J. Phys. G: Nucl. Part. Phys., 2012, 39: 015107; and the reference therein
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MA Chun-Wang, SONG Heng-Li, PU Jie, ZHANG Tong-Lin, ZHANG Sha, WANG Shan-Shan, ZHAO Xin-Li and CHEN Li. Symmetry energy from neutron-rich fragments in heavy-ion collisions, and its dependence on incident energy, and impact parameters[J]. Chinese Physics C, 2013, 37(2): 024102. doi: 10.1088/1674-1137/37/2/024102
MA Chun-Wang, SONG Heng-Li, PU Jie, ZHANG Tong-Lin, ZHANG Sha, WANG Shan-Shan, ZHAO Xin-Li and CHEN Li. Symmetry energy from neutron-rich fragments in heavy-ion collisions, and its dependence on incident energy, and impact parameters[J]. Chinese Physics C, 2013, 37(2): 024102.  doi: 10.1088/1674-1137/37/2/024102 shu
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Received: 2012-03-27
Revised: 1900-01-01
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Symmetry energy from neutron-rich fragments in heavy-ion collisions, and its dependence on incident energy, and impact parameters

    Corresponding author: MA Chun-Wang,

Abstract: The yields of fragments produced in the 60Ni+12C reactions at 80 A and 140 A MeV, and with maximum impact parameters of 1.5, 2 and 7.3 fm at 80 A MeV are calculated by the statistical abrasion-ablation model. The yields of fragments are analyzed by the isobaric yield ratio (IYR) method to extract the coefficient of symmetry energy to temperature (asym/T). The incident energy is found to influence asym/T very little. It's found that asym/T of fragments with the same neutron-excess I=N-Z increases when A increases, while asym/T of isobars decreases when A increases. The asym/T of prefragments is rather smaller than that of the final fragments, and the asym/T of fragments in small impact parameters is smaller than that of the larger impact parameters, which both indicate that asym/T decreases when the temperature increases. The choice of the reference IYRs is found to have influence on the extracted asym/T of fragments, especially on the results of the more neutron-rich fragments. The surface-symmetry energy coefficient (bs/T) and the volume-symmetry energy coefficient (bv/T) are also extracted, and the bs/bv is found to coincide with the theoretical results.

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