Study of the X-ray pulsar IGR J19294+1816 with NuSTAR: detection of cyclotron line and transition to accretion from the cold disc. (arXiv:1811.08912v1 [astro-ph.HE])

Study of the X-ray pulsar IGR J19294+1816 with NuSTAR: detection of cyclotron line and transition to accretion from the cold disc. (arXiv:1811.08912v1 [astro-ph.HE])
<a href="http://arxiv.org/find/astro-ph/1/au:+Tsygankov_S/0/1/0/all/0/1">Sergey S. Tsygankov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Doroshenko_V/0/1/0/all/0/1">Victor Doroshenko</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mushtukov_A/0/1/0/all/0/1">Alexander A. Mushtukov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lutovinov_A/0/1/0/all/0/1">Alexander A. Lutovinov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Poutanen_J/0/1/0/all/0/1">Juri Poutanen</a>

In the work we present the results of two deep broad-band observations of the
poorly studied X-ray pulsar IGR J19294+1816 obtained with the NuSTAR
observatory. The source was observed during Type I outburst and in the
quiescent state. In the bright state a cyclotron absorption line in the energy
spectrum was discovered at $E_{rm cyc}=42.8pm0.7$ keV. Spectral and timing
analysis prove the ongoing accretion also during the quiescent state of the
source. Based on the long-term flux evolution, particularly on the transition
of the source to the bright quiescent state with luminosity around $10^{35}$
erg s$^{-1}$, we concluded that IGR J19294+1816 switched to the accretion from
the “cold” accretion disc between Type I outbursts. We also report the updated
orbital period of the system.

http://arxiv.org/icons/sfx.gif