اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدSearch for the Chiral Magnetic Wave with Anisotropic Flow of Identified Particles at RHIC-STAR
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Qi-Ye Shou
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The chiral magnetic wave (CMW) has been theorized to propagate in the Quark-Gluon Plasma formed in high-energy heavy-ion collisions. It could cause a finite electric quadrupole moment of the collision system, and may be observed as a dependence of elliptic flow, $v_{2}$, on the asymmetry between positively and negatively charged hadrons, $A_{rm ch}$. However, non-CMW mechanisms, such as local charge conservation (LCC) and hydrodynamics with isospin effect, could also contribute to the experimental observations. Here we present the STAR measurements of elliptic flow $v_{2}$ and triangular flow $v_{3}$ of charged pions, along with $v_{2}$ of charged kaons and protons, as functions of $A_{rm ch}$ in Au+Au collisions at $sqrt{s_{rm NN}}$ = 200 GeV. The slope parameters of $Delta v_{2}$($A_{rm ch}$) and $Delta v_{3}$($A_{rm ch}$) are reported and compared to investigate the LCC background. The similarity between pion and kaon slopes suggests that the hydrodynamics is not the dominant mechanism. The difference between the normalized $Delta v_{2}$ and $Delta v_{3}$ slopes, together with the small slopes in p+Au and d+Au collisions at $sqrt{s_{rm NN}}$ = 200 GeV, suggest that the CMW picture remains a viable interpretation at RHIC.
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