Optical and X-ray rebrightening in NS X-ray Nova Aql X-1
ATel #10541; A. Meshcheryakov (IKI, Moscow, Russia), I. Bikmaev, E. Irtuganov, N. Sakhibullin (KFU/AST, Kazan, Russia), V. V.Vlasyuk, O. I.Spiridonova (SAO, Nizhnij Arkhyz, Russia), I. Khamitov (TUG, Antalya, Turkey), P. Medvedev, M. N.Pavlinsky (IKI, Moscow, Russia), S. S.Tsygankov (Tuorla Observatory, Finland)
on 29 Jun 2017; 11:07 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Alexander Meshcheryakov (mesch@iki.rssi.ru)
Subjects: Optical, X-ray, Neutron Star, Transient
The current outburst in NS X-ray Nova Aql X-1 has started ~ 28 May 2017, as it was reported earlier (see ATel#10441, #10450, #10452). During optical monitoring campaign of Aql X-1, performed at 1.5-m Russian-Turkish telescope (TUBITAK National Observatory) and 1-m SAO RAS optical telescope (Special Astrophysical Observatory) we report a substantial increase of optical brightness of Aql X-1 in the last few days.
| MJD (UTC) |
Date |
R,mag |
Instrument |
| 57901.94 | 28 May | 17.54 | 1-m SAO RAS |
| 57902.92 | 29 May | 17.55 | 1-m SAO RAS |
| 57926.90 | 22 Jun | 17.22 | 1-m SAO RAS |
| 57926.97 | 22 Jun | 17.14 | 1.5-m RTT150 |
| 57927.86 | 23 Jun | 17.18 | 1.5-m RTT150 |
| 57927.90 | 23 Jun | 17.18 | 1-m SAO RAS |
| 57928.96 | 24 Jun | 17.46 | 1.5-m RTT150 |
| 57930.93 | 26 Jun | 16.70 | 1-m SAO RAS |
| 57931.90 | 27 Jun | 16.88 | 1-m SAO RAS |
The statistical photometric errors are <1% and ~2% for 1.5-m RTT150 and 1-m SAO RAS, respectivelly.
We estimate absolute photometric calibration error as 3%.
Furthermore, during the last several days (time interval 57925 - 57932 MJD) the Swift BAT light curve of Aql X-1 also shows a factor ~2 continuous brightening (from 0.01 to 0.02 counts/sec/cm^2) in the hard X-rays 15-50keV (see https://swift.gsfc.nasa.gov/results/transients/AqlX-1/). Thus, both X-ray and Optical observations indicate enhancement of accretion activity in NS X-ray Nova Aql X-1.
We encourage further multi-wavelength observations of the source.
