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Title: Understanding the Effect of Conserved Charges on the Coalescence Sum Rule of Directed Flow
Recently, the rapidity-odd directed flow (v1) of produced hadrons (K−, ϕ, p¯, Λ¯, Ξ¯+, Ω−, and Ω¯+) has been studied. Several combinations of these produced hadrons, with very small mass differences but differences in the net electric charge (Δq) and net strangeness (ΔS) on the two sides, have been considered. A difference in v1 between the two sides of these combinations (Δv1) has been proposed as a consequence of the electromagnetic field produced in relativistic heavy-ion collisions, especially if Δv1 increases with Δq. Our study is performed to understand the effect of the coalescence sum rule (CSR) on Δv1. We point out that the CSR leads to Δv1=cqΔq+cSΔS, where the coefficients cq and cS reflect the Δv1 of produced quarks. Equivalently, one can write Δv1=cqΔq+cBΔB, involving the difference in the net baryon number ΔB, where the CSR gives cB=−3cS. We then propose two methods to extract the coefficients for the Δq and ΔS dependences of Δv1.  more » « less
Award ID(s):
2310021 2012947
PAR ID:
10533166
Author(s) / Creator(s):
; ;
Publisher / Repository:
MDPI
Date Published:
Journal Name:
Universe
Volume:
10
Issue:
3
ISSN:
2218-1997
Page Range / eLocation ID:
112
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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