Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV
The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at √sNN=19.6 and 200 GeV. The excess mass spectra are...
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| Format: | Article |
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Elsevier
2018
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| Online Access: | http://hdl.handle.net/1721.1/116630 |
| _version_ | 1826207704869240832 |
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| author | STAR Collaboration van Nieuwenhuizen, Gerrit J |
| author2 | Massachusetts Institute of Technology. Laboratory for Nuclear Science |
| author_facet | Massachusetts Institute of Technology. Laboratory for Nuclear Science STAR Collaboration van Nieuwenhuizen, Gerrit J |
| author_sort | STAR Collaboration |
| collection | MIT |
| description | The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at √sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee<1.1 GeV/c2. The integrated dielectron excess yield at √sNN=19.6 GeV for 0.4<Mee<0.75 GeV/c2, normalized to the charged particle multiplicity at mid-rapidity, has a value similar to that in In+In collisions at √sNN=17.3 GeV. For √sNN=200 GeV, the normalized excess yield in central collisions is higher than that at √sNN=17.3 GeV and increases from peripheral to central collisions. These measurements indicate that the lifetime of the hot, dense medium created in central Au+Au collisions at √sNN=200 GeV is longer than those in peripheral collisions and at lower energies. |
| first_indexed | 2024-09-23T13:53:40Z |
| format | Article |
| id | mit-1721.1/116630 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T13:53:40Z |
| publishDate | 2018 |
| publisher | Elsevier |
| record_format | dspace |
| spelling | mit-1721.1/1166302022-10-01T17:51:54Z Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV STAR Collaboration van Nieuwenhuizen, Gerrit J Massachusetts Institute of Technology. Laboratory for Nuclear Science van Nieuwenhuizen, Gerrit J The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at √sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee<1.1 GeV/c2. The integrated dielectron excess yield at √sNN=19.6 GeV for 0.4<Mee<0.75 GeV/c2, normalized to the charged particle multiplicity at mid-rapidity, has a value similar to that in In+In collisions at √sNN=17.3 GeV. For √sNN=200 GeV, the normalized excess yield in central collisions is higher than that at √sNN=17.3 GeV and increases from peripheral to central collisions. These measurements indicate that the lifetime of the hot, dense medium created in central Au+Au collisions at √sNN=200 GeV is longer than those in peripheral collisions and at lower energies. 2018-06-26T15:54:17Z 2018-06-26T15:54:17Z 2015-08 2015-06 2018-06-26T15:31:25Z Article http://purl.org/eprint/type/JournalArticle 0370-2693 http://hdl.handle.net/1721.1/116630 Adamczyk, L. et al. “Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV.” Physics Letters B 750 (November 2015): 64–71 © 2015 The Authors http://dx.doi.org/10.1016/j.physletb.2015.08.044 Physics Letters B Creative Commons Attribution 4.0 International License http://creativecommons.org/licenses/by/4.0/ application/pdf Elsevier Elsevier |
| spellingShingle | STAR Collaboration van Nieuwenhuizen, Gerrit J Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV |
| title | Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV |
| title_full | Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV |
| title_fullStr | Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV |
| title_full_unstemmed | Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV |
| title_short | Energy Dependence of Acceptance-Corrected Dielectron Excess Mass Spectrum at Mid-Rapidity in Au + Au Collisions at √sNN = 19.6 and 200 GeV |
| title_sort | energy dependence of acceptance corrected dielectron excess mass spectrum at mid rapidity in au au collisions at √snn 19 6 and 200 gev |
| url | http://hdl.handle.net/1721.1/116630 |
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