International Astronomy and Astrophysics Research Journal

A Remark on “Do Triaxial Supermassive Compact Star Exist?”

Ramen Kumar Parui *

Department of Communication, Airports Authority of India, NSCBI Airport, Kolkata, India and Astrophysical Research Centre (ARC), Room No-F101, Mall Enclave, 13, K. B. Sarani, Kolkata- 700080, India.

*Author to whom correspondence should be addressed.

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Abstract

Taking into account three facts — (i) the ambipolar diffusion in Neutron Star core is expected to be the dominant mode of field decay in the early evolution of magnetar ( i.e as long as the ages much less than ~ 10⁴ years), (ii) magnetar field decay is negligible as long as the core temperature (T) is high i.e. few times of 10⁸ K but less than 10⁹ K , (iii) internal magnetic fields remain so strong at the early phase of magnetar that core temperature stays higher than several times 10⁸ K for at least 10³ years (proposed by Dall’Osso et al) we show six magnetars, e.g., SGR1806-20, SwiftJ1818.0-1607, IE1547.0-5408, PSRJ1846-0258, SGR 1900+14 and CX0U J171405.7-381031 are real triaxial stars. These stars will enter into magnetar phase (so called magnetar) after elapse of some periods in triaxial phase. The significance of our result is —a) physically stable triaxial star is possible, b) triaxial phase is stable for a long period ranging from few years to few hundred years, c) detection of such triaxial stars through gravitational waves as well as electro-magnetic counterparts is possible.

Keywords: Gravitational waves, neutron star, magnetar, triaxial star

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