Archival observations of the ultra - soft X - ray transient 4 U 1630 - 47

نویسندگان

  • A. N. Parmar
  • O. R. Williams
چکیده

We report on archival observations of the ultra-soft X-ray transient 4U 1630−47. the region of sky containing 4U 1630−47 and a faint source was detected. While it is possible that this emission originates from another object within the LAC field of view, its properties are consistent with an observation towards the end of an outburst. The times of the Ginga outbursts are consistent with the known ∼600 day ephemeris. However, the ASCA observation and observations of the subsequent outburst by the Rossi X-ray Timing Explorer, indicate that these outbursts started 100–150 days later than predicted. This delay confirms the occurrence of more complex outburst behavior from 4U 1630−47. Finally, an observation by the imaging Einstein HRI in 1980 February, approximately midway between expected outburst times, revealed a faint source at a position consistent with 4U 1630−47. The measured source intensity is higher than the previous best upper-limit. This implies that (a) the quiescent intensity is variable by a factor ∼10, or (b) that the 1979 outburst had an extremely long duration, or (c) that the emission originates from previously undetected inter-outburst activity.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A search for the IR counterpart of the black hole candidate 4 U 1630 - 47

We present the first attempt to localize the IR counterpart of the recurrent, ultra soft X-ray transient 4U 1630-47. We have obtained two sets of K band images of this highly obscured region, during both outburst and quiescence. The recent radio position reported by Hjellming et al. (1999) allow us to perform accurate astrometry on the field. We discuss three stars which lie near the radio posi...

متن کامل

Towards 4U1630−47: a black-hole soft X-ray transient odyssey

4U1630−47 is a black-hole X-ray transient with one of the shortest recurrence times. Despite its regular outburst behaviour little is known about this source. Only recently has attention to this system increased. I discuss there the basic known (X-ray) properties of 4U 1630−47 and report on X-ray and radio observations obtained during its recent outburst, starting in 1998 February. These observ...

متن کامل

X-ray Spectral and Timing Evolution during the Decay of the 1998 Outburst from the Recurrent X-ray Transient 4u 1630–47

We report on the X-ray spectral and timing behavior of the recurrent X-ray transient 4U 1630–47 for 51 RXTE observations made during the decay of its 1998 outburst. The observations began when the source was still relatively bright, and, during one of the early observations, a QPO with a non-Lorentzian profile occurred near 6 Hz. As the source decayed, the X-ray flux dropped exponentially with ...

متن کامل

An Integral Observation of the Black Hole Transient 4u 1630–47 and the Norma Region of the Galaxy

We report on results from a 2003 February INTEGRAL observation of the black hole candidate (BHC) 4U 1630–47 and the high energy sources in the Norma Region of the Galaxy and on RXTE and radio observations of 4U 1630–47. To date, there have been 38 new or previously poorly studied sources found by INTEGRAL (the “IGR” sources), and 15 of the IGR sources are in the field of view of our observation...

متن کامل

The 1998 outburst of the X-ray transient 4U 1630–47 observed with BeppoSAX

We report results of five pointed BeppoSAX observations of the black hole candidate 4U1630–47 during part of its 1998 outburst when the 2–10 keV source luminosity decreased from 2.1×10 erg s (for an assumed distance of 10 kpc) by a factor of ∼7. The 2–200 keV spectrum can be modeled by a soft multi-temperature disk blackbody and a hard power-law. During four of the observations, there is eviden...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2007