Swift XRT finds the M 31 ULX XMMU J004243.6+412519 still active after Sun block
Abstract
We report a detection of the transient ultraluminous X-ray source (ULX) XMMU J004243.6+412519 in M 31 (see ATel's #3890,#3921,#3937,#3959) with the X-ray telescope (XRT) on board the Swift satellite. Soon after the last Swift/XRT observations of the source in early March this year (see ATel #3959) M 31 became unobservable for X-ray telescopes due to Sun constraints. Recently, the visibility window opened again.
- Publication:
-
The Astronomer's Telegram
- Pub Date:
- May 2012
- Bibcode:
- 2012ATel.4125....1H
- Keywords:
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- X-ray;
- Transient