Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisions
The density distributions of large nuclei are typically modeled with a Woods–Saxon distribution characterized by a radius R0 and skin depth a. Deformation parameters β are then introduced to describe non-spherical nuclei using an expansion in spherical harmonics R0(1+β2Y20+β4Y40). But when a nucleus...
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Elsevier
2015-10-01
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Series: | Physics Letters B |
Online Access: | http://www.sciencedirect.com/science/article/pii/S0370269315005985 |
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author | Q.Y. Shou Y.G. Ma P. Sorensen A.H. Tang F. Videbæk H. Wang |
author_facet | Q.Y. Shou Y.G. Ma P. Sorensen A.H. Tang F. Videbæk H. Wang |
author_sort | Q.Y. Shou |
collection | DOAJ |
description | The density distributions of large nuclei are typically modeled with a Woods–Saxon distribution characterized by a radius R0 and skin depth a. Deformation parameters β are then introduced to describe non-spherical nuclei using an expansion in spherical harmonics R0(1+β2Y20+β4Y40). But when a nucleus is non-spherical, the R0 and a inferred from electron scattering experiments that integrate over all nuclear orientations cannot be used directly as the parameters in the Woods–Saxon distribution. In addition, the β2 values typically derived from the reduced electric quadrupole transition probability B(E2)↑ are not directly related to the β2 values used in the spherical harmonic expansion. B(E2)↑ is more accurately related to the intrinsic quadrupole moment Q0 than to β2. One can however calculate Q0 for a given β2 and then derive B(E2)↑ from Q0. In this paper we calculate and tabulate the R0, a, and β2 values that when used in a Woods–Saxon distribution, will give results consistent with electron scattering data. We then present calculations of the second and third harmonic participant eccentricity (ε2 and ε3) with the new and old parameters. We demonstrate that ε3 is particularly sensitive to a and argue that using the incorrect value of a has important implications for the extraction of viscosity to entropy ratio (η/s) from the QGP created in Heavy Ion collisions. |
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issn | 0370-2693 1873-2445 |
language | English |
last_indexed | 2024-12-23T20:38:06Z |
publishDate | 2015-10-01 |
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series | Physics Letters B |
spelling | doaj.art-6f4cad2da9b94588b67dc0a62d9c21f72022-12-21T17:32:01ZengElsevierPhysics Letters B0370-26931873-24452015-10-01749C21522010.1016/j.physletb.2015.07.078Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisionsQ.Y. Shou0Y.G. Ma1P. Sorensen2A.H. Tang3F. Videbæk4H. Wang5Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, ChinaShanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, ChinaBrookhaven National Laboratory, Upton, NY 11973, USABrookhaven National Laboratory, Upton, NY 11973, USABrookhaven National Laboratory, Upton, NY 11973, USABrookhaven National Laboratory, Upton, NY 11973, USAThe density distributions of large nuclei are typically modeled with a Woods–Saxon distribution characterized by a radius R0 and skin depth a. Deformation parameters β are then introduced to describe non-spherical nuclei using an expansion in spherical harmonics R0(1+β2Y20+β4Y40). But when a nucleus is non-spherical, the R0 and a inferred from electron scattering experiments that integrate over all nuclear orientations cannot be used directly as the parameters in the Woods–Saxon distribution. In addition, the β2 values typically derived from the reduced electric quadrupole transition probability B(E2)↑ are not directly related to the β2 values used in the spherical harmonic expansion. B(E2)↑ is more accurately related to the intrinsic quadrupole moment Q0 than to β2. One can however calculate Q0 for a given β2 and then derive B(E2)↑ from Q0. In this paper we calculate and tabulate the R0, a, and β2 values that when used in a Woods–Saxon distribution, will give results consistent with electron scattering data. We then present calculations of the second and third harmonic participant eccentricity (ε2 and ε3) with the new and old parameters. We demonstrate that ε3 is particularly sensitive to a and argue that using the incorrect value of a has important implications for the extraction of viscosity to entropy ratio (η/s) from the QGP created in Heavy Ion collisions.http://www.sciencedirect.com/science/article/pii/S0370269315005985 |
spellingShingle | Q.Y. Shou Y.G. Ma P. Sorensen A.H. Tang F. Videbæk H. Wang Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisions Physics Letters B |
title | Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisions |
title_full | Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisions |
title_fullStr | Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisions |
title_full_unstemmed | Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisions |
title_short | Parameterization of deformed nuclei for Glauber modeling in relativistic heavy ion collisions |
title_sort | parameterization of deformed nuclei for glauber modeling in relativistic heavy ion collisions |
url | http://www.sciencedirect.com/science/article/pii/S0370269315005985 |
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