Two new high-energy γ-ray blazar candidates

Campana, R.; Maselli, A.; Bernieri, E.; Massaro, E.

doi:10.1093/mnras/stw3007

Cited by 12 publications

(8 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This work will contribute to a more comprehensive understanding of the diverse and fascinating γ-ray sky as observed by Fermi. In particular, the community will benefit from the WIBRaLS2 and KDEBLLACS catalogs of candidate blazars presented in this paper and the subsequent programs of follow-up spectroscopic observations needed to confirm their nature and, possibly, determine their redshifts by using them to: (i) improve our knowledge of the luminosity function of BL Lacs (see e.g., Ajello et al 2014); (ii) select potential targets for the Cherenkov Telescope Array (CTA) as shown by Massaro et al (2013c); Arsioli et al (2015) ; (iii) obtain more stringent limits on the dark matter annihilation in sub-halos (see e.g., Zechlin, & Horns 2012;Berlin et al 2014); (iv) search for counterparts of new flaring γ-ray sources (see e.g., Bernieri et al 2013) and of high energy neutrino emission (see e.g., IceCube Collaboration et al 2018); (v) test new γ-ray detection algorithms (see e.g., Campana et al 2015Campana et al , 2016Campana et al , 2017; (vi) and, finally, perform population studies of the remaining UGSs (see e.g., Acero et al 2013).…”

Section: Discussionmentioning

confidence: 99%

Two New Catalogs of Blazar Candidates in the WISE Infrared Sky

D’Abrusco

Crespo

Massaro

et al. 2019

ApJS

View full text Add to dashboard Cite

We present two catalogs of radio-loud candidate blazars whose WISE mid-infrared colors are selected to be consistent with the colors of confirmed γ-ray emitting blazars. The first catalog is the improved and expanded release of the WIBRaLS catalog presented by D' Abrusco et al. (2014): it includes sources detected in all four WISE filters, spatially cross-matched with radio source in one of three radio surveys and radio-loud based on their q 22 spectral parameter. WIBRaLS2 includes 9541 sources classified as BL Lacs, FSRQs or mixed candidates based on their WISE colors. The second catalog, called KDEBLLACS, based on a new selection technique, contains 5579 candidate BL Lacs extracted from the population of WISE sources detected in the first three WISE passbands ([3.4], [4.6] and [12]) only, whose mid-infrared colors are similar to those of confirmed, γ-ray BL Lacs. KDBLLACS members area also required to have a radio counterpart and be radio-loud based on the parameter q 12 , defined similarly to q 22 used for the WIBRaLS2. We describe the properties of these catalogs and compare them with the largest samples of confirmed and candidate blazars in the literature. We crossmatch the two new catalogs with the most recent catalogs of γ-ray sources detected by Fermi LAT instrument. Since spectroscopic observations of candidate blazars from the first WIBRaLS catalog within the uncertainty regions of γ-ray unassociated sources confirmed that ∼ 90% of these candidates are blazars, we anticipate that these new catalogs will play again an important role in the identification of the γ-ray sky.

show abstract

Section: Discussionmentioning

confidence: 99%

Two New Catalogs of Blazar Candidates in the WISE Infrared Sky

D’Abrusco

Crespo

Massaro

et al. 2019

ApJS

View full text Add to dashboard Cite

show abstract

“…The choice of a complete flux-limited sample of bursts ensures to study the lag properties with a sample which is less affected by instrumental selection effects, though being limited in number because composed only by the bright end of the population of Swift GRBs. However, as extensively discussed in several papers Campana et al 2012;D'Avanzo et al 2012;Melandri et al 2012;Nava et al 2012;Covino et al 2013;Ghirlanda et al 2013), the BAT6 sample is suited to study the prompt and afterglow properties of GRBs being almost free from instrumental selection effects: this sample contains all the bursts with favorable observing conditions from ground that Swift has detected above a flux limit of 2.6 ph cm −2 s −1 (in the 15 − 150 keV energy band) and, a posteriori, it has a high degree of completeness in redshift (95%).…”

Section: Sample Selectionmentioning

confidence: 99%

Comparing the spectral lag of short and long gamma-ray bursts and its relation with the luminosity

Bernardini

Ghirlanda

Campana

et al. 2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We investigated the rest frame spectral lags of two complete samples of bright long (50) and short (6) gamma-ray bursts (GRB) detected by Swift. We analysed the Swift /BAT data through a discrete cross-correlation function (CCF) fitted with an asymmetric Gaussian function to estimate the lag and the associated uncertainty. We find that half of the long GRBs have a positive lag and half a lag consistent with zero. All short GRBs have lags consistent with zero. The distributions of the spectral lags for short and long GRBs have different average values. Limited by the small number of short GRBs, we cannot exclude at more than 2 σ significance level that the two distributions of lags are drawn from the same parent population. If we consider the entire sample of long GRBs, we do not find evidence for a lag-luminosity correlation, rather the lag-luminosity plane appears filled on the left hand side, thus suggesting that the lagluminosity correlation could be a boundary. Short GRBs are consistent with the long ones in the lag-luminosity plane.

show abstract

“…Results of our follow up optical campaign were used by several groups to: (i) build the luminosity function of BL Lacs (see e.g., Ajello et al 2014); (ii) select potential targets for the Cherenkov Telescope Array (see e.g., Massaro et al 2013d;Arsioli et al 2015); (iii) obtain stringent limits on the dark matter annihilation in sub-halos (see e.g., Zechlin & Horns 2012;Berlin & Hooper 2014); (iv) search for counterparts of new flaring gamma-ray sources (see e.g., Bernieri et al 2013); (v) test new gamma-ray detection algorithms (see e.g., Campana et al 2015;Campana et al 2016;Campana et al 2017); (vi) perform population studies on the UGSs (see e.g., Acero et al 2013) and (vii) discover the new subclass of radio weak BL Lacs (see e.g., Massaro et al 2017), to name a few.…”

Section: Introductionmentioning

confidence: 99%

Optical spectroscopic observations of gamma-ray blazar candidates VIII: the 2016–2017 follow up campaign carried out at SPM, NOT, KPNO and SOAR telescopes

Marchesini

Peña-Herazo

Crespo

et al. 2019

Astrophys Space Sci

View full text Add to dashboard Cite

The third Fermi source catalog lists 3033 γray sources above 4σ significance. More than 30% are classified as either unidentified/unassociated Gammaray sources (UGSs), with about 20% classified as Blazar candidates of uncertain types (BCUs). To confirm the blazar-like nature of candidate counterparts of UGSs and BCUs, we started in 2012 an optical spectroscopic follow up campaign. We report here the spectra of 36 targets with observations from the Observatorio Astronómico Nacional San Pedro Mártir, the Southern Astrophysical Research Observatory, the Kitt Peak National Observatory and the Northern Optical Telescope, between 2016 and 2017. We confirm the BL Lac nature of 23 sources, and the flat spectrum radio quasar nature of other 7 ones. We also provide redshift estimates for 19 out of these 30 confirmations, with only one being a lower limit due to spectral features ascribable to intervening systems along the line of sight. As in previous analyses, the largest fraction of now-classified BCUs belong to the class of BL Lac objects, that appear to be the most elusive class of active galactic nuclei. One of the BL Lacs identified in this work, associated with 3FGL J2213.6-4755, lies at a redshift of z >1.529, making it one of the few distant gamma-ray BL Lac objects.

show abstract

Two new high-energy γ-ray blazar candidates

Cited by 12 publications

References 30 publications

Two New Catalogs of Blazar Candidates in the WISE Infrared Sky

Two New Catalogs of Blazar Candidates in the WISE Infrared Sky

Comparing the spectral lag of short and long gamma-ray bursts and its relation with the luminosity

Optical spectroscopic observations of gamma-ray blazar candidates VIII: the 2016–2017 follow up campaign carried out at SPM, NOT, KPNO and SOAR telescopes

Contact Info

Product

Resources

About