The blazar 3C345 flare - the strongest one since August 2006
ATel #17498; V. V. Vlasyuk, O. I. Spiridonova (Special Astrophysical Observatory of the Rus. Ac. Sci.)
on 17 Nov 2025; 10:17 UT
Credential Certification: Alexander Moskvitin (mosk@sao.ru)
Subjects: Optical, Blazar
Referred to by ATel #: 17641
Our BVRI-monitoring of the bright blazars sample using by our 1-meter and 0.5-meter reflectors is in progress.
The blazar 3C 345 exhibits enhanced activity in current year: after flare to R = 15.83 +/- 0.01 (epoch March 03/04, MJD 60738.12, see ATel #17059) we detected set of more intense re-brightening (up to R = 15.03 +/- 0.03, MJD 60770.94 (ATel #17134), R = 15.43 +/- 0.02, MJD 60898.84 and R = 15.31 +/- 0.02, MJD 60917.83 respectively).
The last brightening phase of 3C 345 started in last October - after some precursor event at R = 15.88 +/- 0.01, MJD 60961.72 its brightness varied in range 15.9-16.2 mag until November 10th.
But observations on Nov 16/17 night (MJD 60995.66) showed surprisingly powerful flare of 3C345 - R = 14.48 +/- 0.01 mag. According to our long-term monitoring data the blazar was brighter in this century only in August 2006 (R = 14.45 +/- 0.02, MJD 53970.81).
The monitoring of 3C 345 is continuing; the most of data presented were taken under good weather condition (seeing (FWHM) < 2 arcsec and good transparency) and have typical accuracy of individual flux estimates about 0.005 mag. We strongly encourage further multi-wavelength studies.
