A possible mechanism for magnetar soft X-ray/γ-ray emission
Once the energies of electrons near the Fermi surface obviously exceed the threshold energy of the inverse β decay,electron capture（EC） dominates inside the magnetar.Since the maximal binding energy of the 3 P 2 neutron Cooper pair is only about 0.048 MeV,the outgoing high-energy neutrons（E k（n） 60...
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| Published in | Chinese physics B Vol. 21; no. 5; pp. 542 - 554 |
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| Main Author | |
| Format | Journal Article |
| Language | English |
| Published |
01.05.2012
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| Subjects | |
| Online Access | Get full text |
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| Summary: | Once the energies of electrons near the Fermi surface obviously exceed the threshold energy of the inverse β decay,electron capture（EC） dominates inside the magnetar.Since the maximal binding energy of the 3 P 2 neutron Cooper pair is only about 0.048 MeV,the outgoing high-energy neutrons（E k（n） 60 MeV） created by the EC can easily destroy the 3 P 2 neutron Cooper pairs through the interaction of nuclear force.In the anisotropic neutron superfluid,each 3 P 2 neutron Cooper pair has magnetic energy 2μ n B in the applied magnetic field B,where μ n = 0.966 × 10 23 erg.G 1 is the absolute value of the neutron abnormal magnetic moment.While being destroyed by the high-energy EC neutrons,the magnetic moments of the 3 P 2 Cooper pairs are no longer arranged in the paramagnetic direction,and the magnetic energy is released.This released energy can be transformed into thermal energy.Only a small fraction of the generated thermal energy is transported from the interior to the surface by conduction,and then it is radiated in the form of thermal photons from the surface.After highly efficient modulation within the star＇s magnetosphere,the thermal surface emission is shaped into a spectrum of soft X-rays/γ-rays with the observed characteristics of magnetars.By introducing related parameters,we calculate the theoretical luminosities of magnetars.The calculation results agree well with the observed parameters of magnetars. |
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| Bibliography: | Landau levels; Fermi surface; thermal radiation; heat conduction Once the energies of electrons near the Fermi surface obviously exceed the threshold energy of the inverse β decay,electron capture（EC） dominates inside the magnetar.Since the maximal binding energy of the 3 P 2 neutron Cooper pair is only about 0.048 MeV,the outgoing high-energy neutrons（E k（n） 60 MeV） created by the EC can easily destroy the 3 P 2 neutron Cooper pairs through the interaction of nuclear force.In the anisotropic neutron superfluid,each 3 P 2 neutron Cooper pair has magnetic energy 2μ n B in the applied magnetic field B,where μ n = 0.966 × 10 23 erg.G 1 is the absolute value of the neutron abnormal magnetic moment.While being destroyed by the high-energy EC neutrons,the magnetic moments of the 3 P 2 Cooper pairs are no longer arranged in the paramagnetic direction,and the magnetic energy is released.This released energy can be transformed into thermal energy.Only a small fraction of the generated thermal energy is transported from the interior to the surface by conduction,and then it is radiated in the form of thermal photons from the surface.After highly efficient modulation within the star＇s magnetosphere,the thermal surface emission is shaped into a spectrum of soft X-rays/γ-rays with the observed characteristics of magnetars.By introducing related parameters,we calculate the theoretical luminosities of magnetars.The calculation results agree well with the observed parameters of magnetars. 11-5639/O4 Gao Zhi-Fu ,Peng Qiu-He ,Wang Na ,and Chou Chih-Kang a） Xinjiang Astronomical Observatory,Chinese Academy of Sciences,Urumqi 830011,China b） Key Laboratory of Radio Astronomy,Chinese Academy of Sciences,Nanjing 210008,China c） Graduate University of the Chinese Academy of Sciences,Beijing 100080,China d） Department of Astronomy,Nanjing University,Nanjing 210093,China e） National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,China ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
| ISSN: | 1674-1056 2058-3834 1741-4199 |
| DOI: | 10.1088/1674-1056/21/5/057109 |