[vsnet-chat 7115] EXO 2030+375 = V2246 Cyg

[Taichi Kato]

EXO 2030+375 = V2246 Cyg

   Be + neutron star transient X-ray source.  The existence of an initial
peak before the main outburst would be interesting in accordance with the
recent advent of Be + NS accretion disk theory.

   The object is faint in V (highly absorbed), but well observable in the
infrared.

2MASS 203215.264 +373814.91 (2000.0) 12.077 10.804 10.073
203215.1 +373820 (2000.0) EXO2030+375 HMXB(Be) XN 19.60-19.76V
203215.7 +373816 (2000.0) 1RXS_J203215.8+373817 0.539 0.98 0.95
203215.1 +373814 (2000.0) CYGV2246 XP 9.74 10.34 K - - - -

Paper: astro-ph/0506504
Date: Tue, 21 Jun 2005 18:13:07 GMT   (274kb)

Title: INTEGRAL observations of the Be/X-ray binary EXO 2030+375 during
  outburst
Authors: A. Camero Arranz, C.A. Wilson, P. Connell, S. Mart\'inez N\'u\~nez, P.
  Blay, V. Beckmann, V. Reglero
Comments: 10 pages, 11 figures, to be published in A&A
\\
  We present a type-I outburst of the high-mass X-ray binary EXO 2030+375,
detected during INTEGRAL's Performance and Verification Phase in December 2002
(on-source time about 10e+06 seconds). In addition, six more outbursts have
been observed during INTEGRAL's Galactic Plane Scans. X-ray pulsations have
been detected with a pulse period of 41.691798+-0.000016 s. The X-ray
luminosity in the 5-300 keV energy range was 9.7*10e+36 erg/s, for a distance
of 7.1 kpc. Two unusual features were found in the light curve, with an initial
peak before the main outburst and another possible spike after the maximum.
RXTE observations confirm only the existence of the initial spike. Although the
initial peak appears to be a recurrent feature, the physical mechanisms
producing it and the possible second spike are unknown. Moreover, a four-day
delay between periastron passage and the peak of the outburst is observed. We
present for the first time a 5-300 keV broad-band spectrum of this source. It
can be modelled by the sum of a disk black body (kT_bb~8 keV) with either a
power law model with Gamma=2.04+-0.11 keV or a Comptonized component (spherical
geometry, kT_e=30 keV, tau=2.64, kT_W=1.5 keV).
\\ ( http://arXiv.org/abs/astro-ph/0506504 ,  274kb)