Twenty-five typical massive white dwarfs(WDs)are selected and the proton decay reaction catalyzed by magnetic monopoles(MMs)for these WDs is discussed.A velocity-dependent correction factor strongly affects the cross-...Twenty-five typical massive white dwarfs(WDs)are selected and the proton decay reaction catalyzed by magnetic monopoles(MMs)for these WDs is discussed.A velocity-dependent correction factor strongly affects the cross-section.We find that a strong suppression controls the monopole catalysis of nucleon decay by the correction factor.The maximum number of MMs is captured and the luminosity can be 2.235×10^(21)and 1.7859×10^(32)erg s^(-1)(e.g.,for the O+Ne core mass WD J055631.17+130639.78).The luminosities of most massive WDs agree well with the observations at relatively low temperatures(e.g.,T_(6)=0.1),but can be three and two orders of magnitude higher than those of the observations for model(Ⅰ)and(Ⅱ)at relatively high temperatures(e.g.,T_(6)=10),respectively.The luminosities of model(Ⅰ)are about one order of magnitude higher than those of model(Ⅱ).Since we consider the effect of the number of MMs captured on the mass–radius relation and the suppression of the proton decay by the correction factor,the study by model(Ⅱ)may be an improved estimation.展开更多
The binary systems consisting of a Be star and a white dwarf(Be WDs) are very interesting.They can originate from the binaries composed of a Be star and a subdwarf O or B star(Besd OBs),and they can merge into red gia...The binary systems consisting of a Be star and a white dwarf(Be WDs) are very interesting.They can originate from the binaries composed of a Be star and a subdwarf O or B star(Besd OBs),and they can merge into red giants via luminous red nova or can evolve into double WD potentially detected by the LISA mission.Using the method of population synthesis,we investigate the formation and the destiny of Be WDs,and discuss the effects of the metallicity(Z) and the common envelope evolution parameters.We find that Besd OBs are significant progenitors of Be WDs.About 30%(Z = 0.0001)-50%(Z = 0.02) of Be WDs come from Besd OBs.About 60%(Z = 0.0001)-70%(Z = 0.02) of Be WDs turn into red giants via a merger between a WD and a non-degenerated star.About 30%(Z = 0.0001)-40%(Z = 0.02) of Be WDs evolve into double WDs which are potential gravitational waves of the LISA mission at a frequency band between about 3 × 10^(-3)and 3 × 10^(-2)Hz.The common envelope evolution parameter introduces an uncertainty with a factor of about 1.3 on Be WD populations in our simulations.展开更多
基金supported in part by the National Natural Science Foundation of China(NSFC,grant Nos.11965010 and 11565020)the foundation for high-level talents program of Hainan basic and applied basic research program(natural science)under grant 2019RC239+3 种基金the Natural Science Foundation of Hainan Province under grants 118MS071 and 114012the Counterpart Foundation of Sanya under grants 2016PT43 and 2019PT76the Special Foundation of Science and Technology Cooperation for Advanced Academy and Regional of Sanya under grant 2016YD28the Scientific Research Starting Foundation for 515 Talented Project of Hainan Tropical Ocean University under grant RHDRC201701。
文摘Twenty-five typical massive white dwarfs(WDs)are selected and the proton decay reaction catalyzed by magnetic monopoles(MMs)for these WDs is discussed.A velocity-dependent correction factor strongly affects the cross-section.We find that a strong suppression controls the monopole catalysis of nucleon decay by the correction factor.The maximum number of MMs is captured and the luminosity can be 2.235×10^(21)and 1.7859×10^(32)erg s^(-1)(e.g.,for the O+Ne core mass WD J055631.17+130639.78).The luminosities of most massive WDs agree well with the observations at relatively low temperatures(e.g.,T_(6)=0.1),but can be three and two orders of magnitude higher than those of the observations for model(Ⅰ)and(Ⅱ)at relatively high temperatures(e.g.,T_(6)=10),respectively.The luminosities of model(Ⅰ)are about one order of magnitude higher than those of model(Ⅱ).Since we consider the effect of the number of MMs captured on the mass–radius relation and the suppression of the proton decay by the correction factor,the study by model(Ⅱ)may be an improved estimation.
基金the generous support of the Natural Science Foundation of Xinjiang No.2021D01C075the National Natural Science Foundation of China+1 种基金project Nos.12163005,U2031204 and 11863005the science research grants from the China Manned Space Project with No.CMSCSST-2021-A10。
文摘The binary systems consisting of a Be star and a white dwarf(Be WDs) are very interesting.They can originate from the binaries composed of a Be star and a subdwarf O or B star(Besd OBs),and they can merge into red giants via luminous red nova or can evolve into double WD potentially detected by the LISA mission.Using the method of population synthesis,we investigate the formation and the destiny of Be WDs,and discuss the effects of the metallicity(Z) and the common envelope evolution parameters.We find that Besd OBs are significant progenitors of Be WDs.About 30%(Z = 0.0001)-50%(Z = 0.02) of Be WDs come from Besd OBs.About 60%(Z = 0.0001)-70%(Z = 0.02) of Be WDs turn into red giants via a merger between a WD and a non-degenerated star.About 30%(Z = 0.0001)-40%(Z = 0.02) of Be WDs evolve into double WDs which are potential gravitational waves of the LISA mission at a frequency band between about 3 × 10^(-3)and 3 × 10^(-2)Hz.The common envelope evolution parameter introduces an uncertainty with a factor of about 1.3 on Be WD populations in our simulations.
