Continued Optical Flaring in Blazar 1308+326
ATel #15334; Riley M. Corcoran, John J. Slater, Warner S. Neal, Thomas J. Balonek (Colgate Univ., Hamilton, NY USA)
on 18 Apr 2022; 07:55 UT
Credential Certification: Thomas J. Balonek (tbalonek@colgate.edu)
Subjects: Optical, Blazar, Quasar
The blazar 1308+326 (OP +313, AU CVn; z=0.997) is undergoing an optical flare, brightening 1.2 magnitudes in eight days (between 2022 April 10 and 18), reaching R = 14.9 on 2022 April 18.1(UT). 1308+326 is now in the fifth year of an optical outburst that began in early 2018, when it was fainter than R ~ 19.0. During this current outburst it has exhibited multiple flares at optical (ATel #12898, #14727) and gamma-ray wavelengths (ATel #14404).
The observation on 2022 April 18 is the brightest we have seen 1308+326 during the past third-of-a-century in our quasar optical variability monitoring program at Colgate University. It had reached R ~ 15.0-15.5 on several occasions between 2001-2008 and since 2019. To our knowledge, this is the brightest 1308+326 has been observed since the multiple flares reported by multiple observers between 1976 and 1983, when it repeatedly reached an optical brightness corresponding to R ~14.0.
Our preliminary photometric results for 1308+326 for the current observing season, using comparison star C (R = 13.28) of Smith et al (1985, AJ, 90, 1184), are presented below. Observations were obtained with the Colgate University Foggy Bottom Observatory (Hamilton, NY USA) 0.4-m Ferson telescope equipped with an FLI PL1001 CCD camera. The average brightness is calculated from typically one-dozen two-minute images taken in a sequence lasting about half-an-hour.
2021-11-24.39 UT (JD 2,459,542.89) R = 16.13 ± 0.03
2021-12-22.43 UT (JD 2,459,570.93) R = 16.84 ± 0.08
2022-01-27.20 UT (JD 2,459,606.70) R = 16.12 ± 0.04
2022-02-01.17 UT (JD 2,459,611.67) R = 15.64 ± 0.02
2022-02-02.16 UT (JD 2,459,612.66) R = 15.72 ± 0.14
2022-02-16.17 UT (JD 2,459,626.67) R = 16.21 ± 0.07
2022-03-07.18 UT (JD 2,459,645.68) R = 16.32 ± 0.06
2022-03-11.09 UT (JD 2,459,649.59) R = 16.31 ± 0.04
2022-03-22.12 UT (JD 2,459,660.62) R = 15.42 ± 0.02
2022-03-23.09 UT (JD 2,459,661.59) R = 15.39 ± 0.02
2022-03-30.10 UT (JD 2,459,668.60) R = 15.99 ± 0.02
2022-04-05.10 UT (JD 2,459,674.60) R = 16.05 ± 0.02
2022-04-09.10 UT (JD 2,459,678.60) R = 16.15 ± 0.09
2022-04-10.11 UT (JD 2,459,679.61) R = 16.10 ± 0.02
2022-04-13.08 UT (JD 2,459,682.58) R = 15.32 ± 0.02
2022-04-15.08 UT (JD 2,459,684.58) R = 15.25 ± 0.02
2022-04-18.09 UT (JD 2,459,687.59) R = 14.91 ± 0.02
2022-04-18.11 UT (JD 2,459,687.61) R = 14.95 ± 0.02
The individual twenty-four images on 2022 April 18 show a fading of ~0.06 magnitude in 1.1 hours from R = 14.90 to 14.96.
We encourage multi-wavelength observations of this ongoing outburst.
