REM observations of the blazar OJ 287 in NIR
ATel #3682; F. D'Ammando (INAF-IRA Bologna), S. Covino (INAF-OA Brera), D. Fugazza (INAF-OA Brera), E. Molinari (INAF-OA Brera), P. Giommi (ASI/ASDC), A. Giuliani (INAF-IASF Milano), F. Longo (INFN Trieste), E. Pian (SNS Pisa, INAF-OA Trieste), C. M. Raiteri (INAF/OA Torino), P. Romano (INAF-IASF Palermo), M. Tavani (INAF-IASF Roma), A. Treves (Univ. dell'Insubria), S. Vercellone (INAF-IASF Palermo), M. Villata (INAF/OA Torino)
on 13 Oct 2011; 20:51 UT
Credential Certification: Filippo D'Ammando (filippo.dammando@iasf-roma.inaf.it)
Subjects: Infra-Red, AGN, Black Hole, Blazar
Referred to by ATel #: 4026
The Large Area Telescope onboard the Fermi satellite detected a gamma-ray flare from the blazar OJ 287 on 2011 October 10 (ATel #3680). The robotic 60-cm REM telescope located at La Silla (Chile), following a periodical monitoring program, observed automatically the field of the blazar OJ 287 starting from November 2009.
Recently, infrared observations were performed in the J and H bands using REMIR on 2011 October 1, 6, 7, 9, and 11. Preliminary results are reported in the following table.
| Date-Obs | J_mag | H_mag |
| 01/10/11 | 12.90 +/- 0.06 | 12.13 +/- 0.07 |
| 06/10/11 | 12.56 +/- 0.04 | 11.83 +/- 0.10 |
| 07/10/11 | 12.46 +/- 0.09 | 11.67 +/- 0.09 |
| 09/10/11 | 13.05 +/- 0.08 | 12.08 +/- 0.10 |
| 11/10/11 | 13.18 +/- 0.06 | 12.49 +/- 0.08 |
REM observations show an increase in the source flux of about 0.4 magnitude in J band and 0.5 magnitude in H band on 2011 October 7 with respect to the observations of October 1, followed by a rapid decrease. These observations are in agreement with the optical behaviour reported by Larionov et al. (ATel #3681).
REM will continue to monitor the source for our program in the following months.
