Six Swift Observations of the CLAGN NGC 2617

ATel #15804; S. Hoin, S. Bacon, M. Brumback, J. M. Miller, E. Raul, M. T. Reynolds (Univ. of Michigan)
on 12 Dec 2022; 18:45 UT
Credential Certification: Jon Miller (jonmm@umich.edu)

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We report on six observations of the changing look active galactic nucleus (CLAGN) located at the center of the spiral galaxy NGC 2617. The intention of this report is to investigate variations in the X-ray and UV/Optical flux of this CLAGN.

All observations were taken from NASA’s Neil Gehrels Swift Observatory using both the X-ray telescope (XRT) and the UV/Optical telescope (UVOT). Each X-ray flux calculation was done using an absorbed power-law model in Xspec, and N_H was fixed to 3.77 E+20 cm^-2. The central source region was grouped with a minimum of 10 counts per bin unless noted otherwise. All UV/Optical flux density measurements were done using the UW1 filter.

Date | gamma | XRT flux (0.3-10.0 keV) | UVOT flux density |
(MDY) | | (erg/s/cm^2) | (erg/s/cm^2/Ang) |
----------------------------------------------------------------------------------
10/25/22 | 1.31 +1.49/-0.97 | 2.28 +1.82/-1.53 E-12 | 9.02+/- 1.04 E-16 |
10/28/22 | 1.31* | 9.87 +/- 7.85 E-12 | 7.51 +/- 1.23 E-16 |
11/03/22 | 1.87 +0.74/-0.64 | 4.11 +1.54/-1.64 E-12 | 9.23 +/- 1.41 E-16 |
11/09/22 | 1.64 +0.64/-0.58 | 2.32 +0.927/-0.950 E-12 | 7.29 +/- 1.43 E-16 |
11/12/22 | 1.61 +0.75/-0.67 | 2.25 +1.08/-1.11 E-12 | 7.10 +/- 0.92 E-16 |
11/15/22 | 1.61* | 2.53 +/- 1.14 E-12 | 6.78 +/- 1.01 E-16 |

The second observation on October 28th, 2022, had fewer counts from the XRT than the rest of the observations and was grouped with a minimum of 5 counts per bin rather than 10.

The data indicate that the X-ray emission is highly variable on a time scale of days; however, the UV emission is consistent with being constant (within errors). Deeper UV observations may reveal significant variations of smaller amplitude than the X-ray variations.

*The gamma values from the prior observations were frozen.