Further Optical Observations of Aql X-1
ATel #2748; Tolga Guver (Univ. of Arizona), Andrea Kunder (CTIO), and Feryal Ozel (Univ. of Arizona)
on 20 Jul 2010; 21:19 UT
Credential Certification: Tolga Guver (tguver@email.arizona.edu)
Subjects: Optical, Binary, Neutron Star, Transient
Kayhan et al. (ATEL #2742) and Maitra et al. (ATEL #2744) recently
reported a new outburst of the low mass X-ray binary Aql X-1.
Following these reports, we observed the source in the B and R bands using
the 90" Bart J. Bok Telescope of the Steward Observatory at Kitt
Peak on July 19 UTC. Using the 90Prime detector, we obtained R and B
band images with exposure times of 250 and 500 seconds at JD
2455396.8494 and 2455396.8227, respectively.
We converted instrumental magnitudes to the standard system using 9
nearby stars and the USNO B1.0 catalog (Monet et al. 2003). We found
that the R and B band magnitudes of the source are 17.187 +/-
0.015 and 18.722 +/- 0.011. As in Maitra et al., our magnitudes
include the unrelated interloper 0.5" away (Chevalier et al. 1999;
Maitra & Bailyn 2008).
These measurements show that the optical brightness of the source
continues to increase.
Due to overcast weather conditions no future observations are planned.