Exploring effects of magnetic field on the Hadron Res- onance Gas

We present a study of the effects of magnetic fields on fluctuations and correlations in hadron resonance gas model. We find significant changes in the fluctuations of net baryon number, electric charge and strangeness. This is also reflected in various fluctuation ratios along the freezeout curve. Introduction. – Heavy-ion collisions (HIC) are investigated both theoretically and experimentally to understand the properties of nuclear matter at extreme conditions. One of the most important issues addressed in HIC is the possibility for nuclear matter to undergo a phase transitions to quark matter. At low baryon density and high temperature nuclear matter is expected to smoothly cross over [1] to a quark gluon plasma (QGP) phase. Whereas, at high baryon density and low temperature the system is expected to have a first order phase transition [2–4]. The study of the effect of magnetic field on the phase transition has become a subject of intense research for last few years. The phase transition in Quantum Chromodynamic (QCD) system is usually expected to occur around the QCD energy scales Λ ∼ 200 MeV. So one should be interested in the magnetic fields with strength B ∼ (200 MeV) ∼ 2×1018 G. Non-central relativistic HIC may create extremely strong magnetic field (∼ mπ ∼ 10G) due to the relativistic motion of the charged particles. The magnetic field (B) may reach up to order of 0.1mπ, m 2 π and 15m 2 π for SPS, RHIC and LHC energies respectively [5]. Magnetic fields can induce many interesting phenomena in QCD matter. For example the chiral magnetic effect, i.e., electric charge separation induced by chirality imbalance, along an external magnetic field, which also results in P and CP violation [6,7]. On the other hand, magnetic catalysis [8] and inverse magnetic catalysis [9,10] can affect the phase diagram of QCD matter. Lattice QCD studies show that in the presence of magnetic field the critical temperature may increase [11, 12]. Effects on hadron mass modification has also been reported [13]. The presence of magnetic fields may increase the fluctuations and correlations [14], as well as elliptic flow coefficient [15] of hot QCD matter. Anisotropic electric conductivity of hadronic matter is an effect of strong magnetic field which has been found in lattice studies [16]. Such anisotropy in conductivity should create an anisotropy in the dilepton