1. RRI Digital Repository
  2. 04. Astronomy and Astrophysics
  3. Research Papers (A&A)
Please use this identifier to cite or link to this item: http://hdl.handle.net/2289/6455
Full metadata record
DC FieldValueLanguage
dc.contributor.authorGiroletti, M.-
dc.contributor.authorMassaro, F.-
dc.contributor.authorDeshpande, A.A.-
dc.contributor.authorUdaya Shankar, N.-
dc.contributor.authorSrivani, K.S.-
dc.contributor.authorSubrahmanyan, Ravi-
dc.contributor.author+30 Co-authors-
dc.date.accessioned2016-10-19T06:21:05Z-
dc.date.available2016-10-19T06:21:05Z-
dc.date.issued2016-04-
dc.identifier.citationAstronomy and Astrophysics, 2016, Vol.588, A141en_US
dc.identifier.issn0004-6361-
dc.identifier.issn1432-0746 (Online)-
dc.identifier.urihttp://hdl.handle.net/2289/6455-
dc.descriptionOpen Accessen_US
dc.description.abstractContext. Low-frequency radio arrays are opening a new window for the study of the sky, both to study new phenomena and to better characterize known source classes. Being flat-spectrum sources, blazars are so far poorly studied at low radio frequencies. Aims. We characterize the spectral properties of the blazar population at low radio frequency, compare the radio and high-energy properties of the gamma-ray blazar population, and search for radio counterparts of unidentified gamma-ray sources. Methods. We cross-correlated the 6100 deg2 Murchison Widefield Array Commissioning Survey catalogue with the Roma blazar catalogue, the third catalogue of active galactic nuclei detected by Fermi-LAT, and the unidentified members of the entire third catalogue of gamma-ray sources detected by Fermi-LAT. When available, we also added high-frequency radio data from the Australia Telescope 20 GHz catalogue. Results. We find low-frequency counterparts for 186 out of 517 (36%) blazars, 79 out of 174 (45%) gamma-ray blazars, and 8 out of 73 (11%) gamma-ray blazar candidates. The mean low-frequency (120–180 MHz) blazar spectral index is ⟨αlow⟩ = 0.57 ± 0.02: blazar spectra are flatter than the rest of the population of low-frequency sources, but are steeper than at ~GHz frequencies. Low-frequency radio flux density and gamma-ray energy flux display a mildly significant and broadly scattered correlation. Ten unidentified gamma-ray sources have a (probably fortuitous) positional match with low radio frequency sources. Conclusions. Low-frequency radio astronomy provides important information about sources with a flat radio spectrum and high energy. However, the relatively low sensitivity of the present surveys still misses a significant fraction of these objects. Upcoming deeper surveys, such as the GaLactic and Extragalactic All-Sky MWA (GLEAM) survey, will provide further insight into this population.en_US
dc.language.isoenen_US
dc.publisherEDP Sciences for European Southern Observatoryen_US
dc.relation.urihttp://adsabs.harvard.edu/abs/2016A%26A...588A.141Gen_US
dc.relation.urihttp://arxiv.org/abs/1602.08869en_US
dc.relation.urihttp://dx.doi.org/10.1051/0004-6361/201527817en_US
dc.rights2016 European Southern Observatoryen_US
dc.titleHigh-energy sources at low radio frequency: the Murchison widefield array view of Fermi blazarsen_US
dc.typeArticleen_US
Appears in Collections:Research Papers (A&A)

Files in This Item:
File Description SizeFormat 
2016_A&A_588_A141.pdf
  Restricted Access		Open Access280.93 kBAdobe PDFView/Open Request a copy
2016_A&A_588_A141.epub
  Restricted Access		Open Access1.02 MBEPUBView/Open Request a copy
Show simple item record


Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.