Recent Results on the CME and the EM Field Effects from the RHIC BES Program

Relativistic heavy-ion collisions produce a quark-gluon plasma (QGP) under rapid evolution with intense, transient electromagnetic fields generated in noncentral collisions. These conditions allow the study of QCD matter under extreme conditions, including anomalous chiral transport phenomena such as the chiral magnetic effect (CME) and electromagnetic-field-induced modifications of collective dynamics. We review recent STAR Collaboration results from the BES-II program, including Au+Au collisions at s N N = 7.7 –27 GeV, which provide a unique probe for QGP properties near the QCD phase boundary. The CME measurements benefit from improved background suppression and exhibit a finite residual charge separation between 10–20 GeV. These data also enable data-driven model inference to quantitatively extract chiral transport parameters. Additionally, charge-dependent directed flow splitting for identified hadrons and hyperons, together with conserved-charge correlations, provides complementary probes of the electromagnetic response and transport properties of the QGP.