Magnetic monopole energy cooling source model of old white dwarf stars

Abstract

In this paper, we mainly focus on 22 old white dwarfs and present two new magnetic monopoles (MMs) energy cooling resources models (I) and (II) based on MMs catalytic nuclear decay. We discussed their luminosity, and compared with the observations. The luminosities for these old White Dwarf stars (WDs) for models (I) and (II) are well in agreement with the observations [Formula: see text] and the differences are no more than one order magnitude at relativistic low temperature (e.g. [Formula: see text]). However, at relativistic high temperature (e.g. [Formula: see text]), the observations [Formula: see text] can be four and two orders of magnitude lower than those of models (I) and (II), respectively. We also compared the results of models (I) and (II) by scaling factor [Formula: see text]. One can see that the maximum of the luminosities for model (I) are 185.2705 and 512.7054 times larger than those of model (II) for old WD [Formula: see text] at [Formula: see text], 10, respectively. On the other hand, the minimum of the luminosities for model (I) are 7.3563 and 34.8064 times larger than those of model (II) for old WD 1444-175 at [Formula: see text], 10, respectively. By considering the effect on the mass radius relationship by the number of the MMs captured in WDs and catalytic nuclear decay, our results show that the study of model (II) may be an improving estimation, and the monopole-catalyzed nucleon decay process could be preventing white dwarfs from cooling down into a stellar graveyard by keeping them hot.