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SMARTS O/IR Photometry of recently flaring blazar 3C 454.3

ATel #7981; E. MacPherson, I. Hasan, C. Bailyn, M. Urry (Yale University), J. Isler (Vanderbilt University)
on 2 Sep 2015; 18:43 UT
Credential Certification: Jedidah Isler (jedidah.isler@vanderbilt.edu)

Subjects: Infra-Red, Optical, AGN, Blazar, Quasar

As part of our O/IR blazar program, we monitor gamma-ray-bright blazars with the SMARTS 1.3m+ANDICAM instrument in Cerro Tololo, Chile. The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope recently detected strongly increasing gamma-ray flux from blazar 3C 454.3. A significant increase in its VLBI core brightness on 2 July 2015 was recently reported by S. Jorstad et al. (ATel#7942). L. Carrasco et al. report increased NIR flux on 22 August 2015 (ATel#7950).

We have visited 3C 454.3 on a nightly cadence (as weather permitted) throughout this most recent flare. We report the following O/IR magnitudes at our brightest detection, also on 22 August 2015 (JD 2457256.67688):
B_mag = 15.13
V_mag = 14.56
R_mag = 14.03
J_mag = 12.19
K_mag = 10.13
with estimated errors +/- 0.03 mag in the optical and +/- 0.05 mag in the near-infrared.

We are conducting a long-term O/IR monitoring campaign of 3C 454.3, which began in June 2008. On 22 June 2014 (JD 2456831.82530), this source was detected at record brightness (ATel#6266). For comparison, the August 2015 flare is slightly dimmer as follows:
del_B = 1.17 mag
del_V = 1.12 mag
del_R = 1.06 mag
del_J = 0.80 mag
del_K = 0.58 mag

These data may be visualized using our SMARTScience Tools here: http://www.astro.yale.edu/smarts/glast/form.html
Long-term light curve: http://www.astro.yale.edu/smarts/glast/plots/3C454.jpg
Data Table: http://www.astro.yale.edu/smarts/glast/tables/3C454.tab

SMARTS Optical/IR Observations of Fermi Blazars