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AGN in the INTEGRAL/IBIS 9-year Galactic hard X-ray survey

ATel #4151; P. Parisi (INAF/IAPS, INAF/IASF Bologna), N. Masetti, L. Bassani, R. Landi (INAF/IASF Bologna), V. Chavushyan (INAOE, Puebla), E. Jimenez-Bailon (UNAM, Mexico City), L. Morelli (Univ. Padova), A. Bazzano (INAF/IAPS), A. J.Bird (Univ. Southampton), P. Ubertini (INAF/IAPS).
on 5 Jun 2012; 16:12 UT
Credential Certification: Pietro Parisi (pietro.parisi@iaps.inaf.it)

Subjects: Optical, X-ray, Gamma Ray, AGN

With respect to the recent INTEGRAL/IBIS 9-year Galactic Hard X-ray Survey (Krivonos et al. 2012, arXiv:1205.3941) we report the identification of a number of sources with active galactic nuclei (AGN) as detailed in the following (coordinates refer to epoch J2000):

Swift J0250.2+4650: On 2008 December 3, starting at 05.52 UT, we acquired optical spectra of the 2MASS extended source 2MASX J02502722+4647295 (RA = 02 50 27.2, DEC = +46 47 29.5), associated with SWIFT J0250.2+4650 (Krivonos et al. 2012, arXiv:1205.3941); data were obtained using the Boller & Chivens spectrograph mounted on the 2.1m telescope of the Observatorio Astronomico Nacional (San Pedro Martir, Baja California, Mexico) for a total exposure time of 3600s. Narrow redshifted emission lines (Halpha, Hbeta and [OIII]) were detected, which allow the firm classification of the source as a Seyfert 2 AGN at redshift z = 0.021 +/- 0.001.

IGR J05470+5034: This source is associated with the SWIFT/BAT object SWIFT J0547.4+5042 (see http://heasarc.gsfc.nasa.gov/docs/swift/results/bs58mon/ ). There is only one source detected by XRT at 5.2 sigma c.l. (0.3-10 keV) within the intersection of IBIS and BAT positional uncertainties: it is located at RA = 05 47 14.76, DEC = +50 38 24.4 (5.0 arcsec uncertainty). This position is compatible with that of the 2MASS extended source 2MASX J05471492+5038251 classified in NED as a galaxy at z=0.035. Through the AFOSC spectrograph mounted on the 1.8m 'Copernicus' telescope at the Astrophysical Observatory of Asiago (Italy), on 2011 March 1, starting at 21.19 UT, we obtained optical spectra of this galaxy for a total exposure time of 3600s. Again in this case, narrow redshifted Halpha, Hbeta and [OIII] emission lines were detected, allowing the classification of the source as a Seyfert 2 with redshift 0.036 +/- 0.001, confirming the redshift reported in the NED database.

Swift J1933.9+3258: We note that this source, not classified in the Krivonos et al. 2012 survey, is identified with a Seyfert 1 at z= 0.058 in ATel #859, ATel #862, ATel #869 and in Landi et al. (2007, ApJ, 669, 109). We here stress that the redshift in Landi et al. 2007 was incorrectly reported as 0.063 +/- 0.001. It should have been read as 0.059 +/- 0.001.

We thank G. Martorana and M. Rebeschini for the observations performed in service mode at the Asiago Telescope.