Spin-polarized states in neutron matter in a strong magnetic field

Abstract

Spin polarized states in neutron matter at strong magnetic fields up to 10 18 G are considered in the model with the Skyrme effective interaction. By analyzing the self-consistent equations at zero temperature, it is shown that a thermodynamically stable branch of solutions for the spin polarization parameter as a function of density corresponds to the negative spin polarization when the majority of neutron spins are oriented opposite to the direction of the magnetic field. Besides, beginning from some threshold density dependent on the magnetic field strength the self-consistent equations have also two other branches of solutions for the spin polarization parameter with the positive spin polarization. The free energy corresponding to one of these branches turns out to be very close to that of the thermodynamically preferable branch. As a consequence, at a strong magnetic field, the state with the positive spin polarization can be realized as a metastable state at the high density region in neutron matter which under decreasing density at some threshold density changes into a thermodynamically stable state with the negative spin polarization.

Nuclear response for the Skyrme effective interaction with zero-range tensor terms. III. Neutron matter and neutrino propagation

“…Since the construction of an Energy Density Functional (EDF) reliable for both symmetric matter and neutron matter is of fundamental importance [3,4], we present here the response functions and some associated sum rules for Pure Neutron Matter (PNM) with the same approach. The interest of the present study is related to spin susceptibilities and ferromagnetic finite size instabilities in neutron matter [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Moreover, we use these results to study the impact of the tensor terms on the determination of the neutrino mean free path in PNM.…”

Anisotropic pressure in dense neutron matter under the presence of a strong magnetic field

“…However, we will assume, analogously to the previous studies [9,11,14], that, because of the tiny value of the neutron magnetic moment, the contribution of the magnetization to the inner magnetic field B remains small for all relevant densities and magnetic field strengths, and, hence,…”

“…Note that, unlike to Refs. [14,15], the term with the external magnetic field H is not included in the single particle energy ε but is separately introduced in the exponent of the Fermi distribution (2).…”

“…In the interior of a magnetar the magnetic field strength may be even larger, reaching values of about 10 18 G [8,9]. Under such circumstances, the issue of interest is the behavior of neutron star matter in a strong magnetic field [8,9,10,11,12,13,14,15].…”

Equation of state of strange quark matter in a nonuniform magnetic field

“…Strong magnetic fields can have significant impact on thermodynamic properties of strongly interacting matter in the dense interior of a compact star. [19][20][21][22][23][24] In particular, because of the breaking of the rotational symmetry, the pressure becomes essentially anisotropic in strongly magnetized matter. [25][26][27][28][29] .…”