Swift Monitoring of the AGN Outburst in NGC2617: Significant X-ray and UV Brightening
ATel #5059; B. J. Shappee (Ohio State), D. Grupe (Penn State), S. Mathur (Ohio State), J. L. Prieto (Princeton), C. S. Kochanek, K. Z. Stanek, J. Jencson, A. Talabere, J. F. Beacom (Ohio State), D. Szczygiel, G. Pojmanski (Warsaw University Observatory), M. Dubberley, M. Elphick, S. Foale, E. Hawkins, D. Mullens, W. Rosing, R. Ross, Z. Walker (Las Cumbres Observatory)
on 8 May 2013; 21:55 UT
Credential Certification: Benjamin Shappee (shappee@astronomy.ohio-state.edu)
Following the ASAS-SN discovery of a strong optical outburst and Seyfert type change in the nucleus of NGC 2617 (Shappee et al. 2013, ATel #5010), we obtained seven (eight) Swift TOO observations of this source with the XRT (UVOT), respectively, from 2013 UT May 1 to 2013 UT May 8. The lightcurve of these observations can be found here. The UVOT observations were extracted using a 5" aperture. All UVOT magnitudes have been measured in the Vega system and are corrected for Galactic extinction.
From 2013 UT May 3.80 to 2013 UT May 8.04, we see an increase in the X-ray flux by a factor of four while the X-ray spectrum softened slightly. On UT date 2013 UT May 8.04 the observed X-Ray flux was 9.14e-11 ergs/cm^2/s (0.2--12 keV) which is over an order of magnitude greater than the flux in 2007 observed by XMM-Newton of 9.0e-12 ergs/cm^2/s. Additionally, the UV flux appears to be increasing on a longer timescale. From 2013 UT May 3.80 to 2013 UT May 8.04 the W2 flux has increased by more than 75%. However, the fractional increase of the UV flux intrinsic to the AGN is actually greater than 75% because the 5" aperture used to extract the UVOT photometry contains a significant amount of light from the host galaxy.
Continued follow-up is both planned and encouraged.
We thank the Swift TOO team for promptly scheduling and executing these observations.
