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Abstract In nuclear collisions at RHIC energies, an excess of$$\Omega$$ hyperons over$$\bar{\Omega }$$ is observed, indicating that$$\Omega$$ has a net baryon number despitesand$$\bar{s}$$ quarks being produced in pairs. The baryon number in$$\Omega$$ may have been transported from the incident nuclei and/or produced in the baryon-pair production of$$\Omega$$ with other types of anti-hyperons such as$$\bar{\Xi }$$ . To investigate these two scenarios, we propose to measure the correlations between$$\Omega$$ andKand between$$\Omega$$ and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport (AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the$$\Omega$$ -hadron correlations from simulated Au+Au collisions at$$\sqrt{s_\text{NN}} = 7.7$$ and$$14.6 \ \textrm{GeV}$$ and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions.
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Baryon Number Transport, Strangeness Conservation and Ω-hadron Correlations
Although strange quarks are produced in ss¯ pairs, the ratio of Ω − to Ω¯ + is greater than one in heavy-ion collisions at lower RHIC energies. Thus the produced Ω hyperons must carry net baryon quantum numbers from the colliding nuclei. We present results of K-Ω correlations from AMPT model simulations of Au+Au collisions at √S NN = 14.6 GeV, to probe dynamics for baryon number transport to mid-rapidities at this beam energy. We use both the default and string-melting versions to illustrate how hadronization schemes of quark coalescence and string fragmentations could leave imprints on such correlations. Implications on the measurements of these correlations with the STAR experiment at RHIC will also be discussed.
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- Award ID(s):
- 2012947
- PAR ID:
- 10428036
- Editor(s):
- Kim, Y.; Moon, D.H.
- Date Published:
- Journal Name:
- EPJ Web of Conferences
- Volume:
- 276
- ISSN:
- 2100-014X
- Page Range / eLocation ID:
- 03002
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1051/epjconf/202327603002
