Cyclotron emission, absorption, and the two faces of X-ray pulsar A 0535+262



: Tsygankov SS, Doroshenko V, Mushtukov AA, Suleimanov VF, Lutovinov AA, Poutanen J

Publisher: OXFORD UNIV PRESS

: 2019

: Monthly Notices of the Royal Astronomical Society

: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

: MON NOT R ASTRON SOC

: 487

: 1

: L30

: L34

: 5

: 0035-8711

DOI: https://doi.org/10.1093/mnrasl/slz079

: https://research.utu.fi/converis/portal/detail/Publication/42543801


Deep NuSTAR observation of X-ray pulsar A 0535+262, performed at a very low luminosity of similar to 7 x 10(34) erg s(-1), revealed the presence of two spectral components. We argue that the high-energy component is associated with cyclotron emission from recombination of electrons collisionally excited to the upper Landau levels. The cyclotron line energy of E-cyc = 47.7 +/- 0.8 keV was measured at the luminosity of almost an order of magnitude lower than what was achieved before. The data firmly exclude a positive correlation of the cyclotron energy with the mass accretion rate in this source.

Last updated on 2024-26-11 at 15:08