We study the properties of β-equilibrated electrically charged neutral quark-star matter at zero temperature and finite magnetic field, and derive the equation of state. The mass and radius of strange stars are constructed for absolutely stable three-flavor quark matter, where the energy per baryon number lies below the energy per baryon for ${}^{56}\mathrm{Fe}.$ The effect of the magnetic field on the electrostatic potential of electrons inside and in close vicinity outside the quark surface of the star is studied. We find that the interior magnetic field $H<~{10}^{18}\mathrm{G}$ does not change the mass and radius of the equilibrium star appreciably, but changes the interior structure of a star. Depending on the value of the crust potential and the electron chemical potential at the base of the nuclear crust, our studies show that the strong surface magnetic field $1.0\times {10}^{14}<~H<~3.0\times {10}^{16}\mathrm{G}$ leads to a considerable reduction of the electrostatic potential which is responsible for the tunneling of ions from the nuclear crust towards the quark surface. For those values of the magnetic fields, strange stars are unlikely to possess a thick nuclear crust. The magnetic field intensity lying outside this range does not have any effect on the crust mass.

• Received 14 September 1999

DOI:https://doi.org/10.1103/PhysRevD.62.023002