RXTE ASM Detection of an Outburst from Aql X-1
ATel #1216; R. H.D. Corbet (UMBC and NASA/GSFC), R. A. Remillard (MIT/MKI), A. M. Levine (MIT/MKI), F. E. Marshall (NASA/GSFC), and T. E. Strohmayer (NASA/GSFC) report for the RXTE ASM team at NASA/GSFC and MIT
on 14 Sep 2007; 21:24 UT
Distributed as an Instant Email Notice Request For Observations
Credential Certification: Robin Corbet (corbet@gsfc.nasa.gov)
Subjects: X-ray, Binary, Neutron Star, Transient
Observations with the Rossi X-ray Timing Explorer (RXTE)
All-Sky Monitor (ASM) of the soft X-ray transient
Aquila X-1 reveal a recent increase in flux that indicates that an
outburst is in progress.
Recent daily average measurements with the RXTE ASM in the
2 - 12 keV energy range are:
MJD 54351.318008, 0.9 +/- 0.5 cts/s;
54352.5, 3.4 +/- 0.2;
54353.4, 5.2 +/- 0.4;
54354.6, 7.1 +/- 0.4;
54355.3, 8.7 +/- 0.5;
54357.2, 13.1 +/- 0.4.
For comparison, the Crab produces 75.5 cts/s in the ASM. The ASM flux
from Aql X-1 is now higher than the outburst in May 2007 first
detected by Rodriguez et al. (ATEL #1079) and higher than any daily
average flux seen with the ASM since at least MJD 53720 (December
2005).
