A Short Hard X-ray Flare from the Blazar NRAO 530 Observed by INTEGRAL

Abstract

We report about a short flare from the blazar NRAO 530 occurred on 17 February 2004 and detected serendipitously by the IBIS/ISGRI detector on board INTEGRAL. In the 20-40 keV energy range, the source, that is otherwise below the detection limit, is detected at a level of ~2 x 10^-10 erg cm^-2 s^-1 during a time interval of less than 2000 s, which is about a factor 2 above the detection threshold. At other wavelengths, only nearly-simultaneous radio data are available (1 observation at 2 cm on 11 February 2004), indicating a moderate increase of the polarization. This appears to be the shortest time variability episode ever detected in a high luminosity blazar at hard X-rays, unless the blazar is contaminated by the presence of an unknown unresolved rapidly varying source.

arXiv comment5 pages, 4 figures. Accepted for publication on A&A Main Journal. Note added in proof

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• XMM-Newton timing mode observations of Mrk 421
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• INTEGRAL observations of the field of the BL Lacertae object S5~0716+714

Cited by in corpus (12)

• Search for the shortest variability at gamma rays in flat-spectrum radio quasars
• Locating the gamma-ray emission region of the flat spectrum radio quasar PKS 1510-089
• Low energy cut-offs and hard X-ray spectra in high-z radio-loud quasars: the Suzaku view of RBS315
• Fermi LAT detection of extraordinary variability in the gamma-ray emission of the blazar PKS 1510-089
• Swift observations of high-redshift radio-loud quasars
• Discovery of an Extreme MeV Blazar with the Swift Burst Alert Telescope
• The Event Horizon Telescope Image of the Quasar NRAO 530
• Does the gamma-ray flux of the blazar 3C 454.3 vary on sub-hour timescales?
• GENJI Programme: Gamma-ray Emitting Notable AGN Monitoring by Japanese VLBI
• High-frequency very long baseline interferometry studies of NRAO 530
• Discovery of two new Fast X-ray Transients with INTEGRAL: IGR J03346+4414 and IGR J20344+3913
• INTEGRAL high energy detection of the transient IGR J11321-5311