English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The rapidity-odd directed flows ($v_{\rm 1}$) of identified hadrons areexpected to follow the coalescence sum rule when the created matter isinitially in parton degrees of freedom and then hadronizes through quarkcoalescence. A recent study has considered the $v_{\rm 1}$ of produced hadronsthat do not contain $u$ or $d$ constituent quarks. It has constructed multiplehadron sets with a small mass difference but given difference in electriccharge $\Delta q$ and strangeness $\Delta S$ between the two sides, where anonzero and increasing $\Delta v_{\rm 1}$ with $\Delta q$ has been proposed tobe a consequence of electromagnetic fields. In this study, we examine theconsequence of coalescence sum rule on the $\Delta v_{\rm  1}$ of the hadron sets in the absence of electromagnetic fields. We find thatin general $\Delta v_{\rm 1} \neq 0$ for a hadron set with nonzero $\Delta q$and/or $\Delta S$ due to potential $v_{\rm 1}$ differences between $\bar u$ and$\bar d$ and between $s$ and $\bar s$ quarks. We further propose methods toextract the coefficients for the $\Delta q$- and $\Delta S$-dependences of thedirect flow difference, where a nonzero constant term would indicate thebreaking of the coalescence sum rule. The extraction methods are thendemonstrated with transport model results.

Coalescence sum rule and the electric charge- and strangeness-dependences of directed flow in heavy ion collisions