A two-flavor color superconducting (2SC) Nambu-Jona-Lasinio (NJL) model is introduced at finite t... more A two-flavor color superconducting (2SC) Nambu-Jona-Lasinio (NJL) model is introduced at finite temperature T , chemical potential µ and in the presence of a constant magnetic field ẽB. The effect of (T, µ, ẽB) on the formation of chiral and color symmetry breaking condensates is studied. The complete phase portrait of the model in T -µ, µ -ẽB, and T -ẽB phase spaces for various fixed ẽB, T , and µ is explored. A threshold magnetic field ẽB t ≃ 0.5 GeV 2 is found above which the dynamics of the system is solely dominated by the lowest Landau level (LLL) and the effects of T and µ are partly compensated by ẽB.
The color neutral two-flavor superconducting (2SC) phase of cold and dense quark matter is studie... more The color neutral two-flavor superconducting (2SC) phase of cold and dense quark matter is studied in the presence of constant magnetic fields and at moderate baryon densities. In the first part of the paper, a two-flavor effective Nambu-Jona-Lasinio (NJL) model consisting of a chiral symmetry breaking (χSB) mass gap σ B , a color superconducting (CSC) mass gap ∆ B and a color chemical potential µ 8 is introduced in the presence of a rotated U (1) magnetic fieldB. To study the phenomenon of magnetic catalysis in the presence of strong magnetic fields, the gap equations corresponding to σ B and ∆ B , as well as µ 8 are solved in the lowest Landau level (LLL) approximation. In the second part of the paper, a detailed numerical analysis is performed to explore the effect of any arbitrary magnetic field on the above mass gaps and the color chemical potential. The structure of the χSB and CSC phases is also presented in the µ c −ẽB plane, and the effect of µ 8 on the phase structure of the model is explored. As it turns out, whereas the transition from the χSB to CSC phase is of first order, nonvanishing µ 8 affects essentially the second order phase transition from CSC to the normal phase.
We study the properties of a hot and magnetized quark matter in a rotating cylinder in the presen... more We study the properties of a hot and magnetized quark matter in a rotating cylinder in the presence of a constant magnetic field. To do this, we solve the corresponding Dirac equation using the Ritus eigenfunction method. This leads to the energy dispersion relation, Ritus eigenfunctions, and the quantization relation for magnetized fermions. To avoid causality-violating effects, we impose a certain global boundary condition, and study its effect, in particular, on the energy eigenmodes and the quantization relations of fermions. Using the fermion propagator arising from this method, we then solve the gap equation at zero and nonzero temperatures. At zero temperature, the dynamical massm does not depend on the angular frequency, as expected. We thus study its dependence on the distance r relative to the axis of rotation and the magnetic field B, and explore the corresponding finite size effect for various couplings G. We then consider the finite temperature case. The dependence ofm on the temperature T , magnetic field B, angular frequency Ω, and distance r for various G is studied. We show thatm decreases, in general, with B and Ω. This is the "inverse magneto-rotational catalysis (IMRC)" or the "rotational magnetic inhibition", previously discussed in the literature. To explore the evidence of this effect in the phase diagrams of our model, we examine the phase portraits of the critical temperature Tc as well as the critical angular frequency Ωc with respect to G, B, Ω, and r as well as G, B, T , and r, respectively. We show that Tc and Ωc decrease, in particular, with B. This is interpreted as clear evidence for IMRC.
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Papers by Neda Sadooghi