Search for high-redshift blazars with Fermi/LAT
Kreter M, Gokus A, Kadler M, Krauß F, Buson S, Ojha R, Wilms J, Böttcher M (2019)
Publication Type: Conference contribution
Publication year: 2019
Journal
Publisher: Sissa Medialab Srl
Book Volume: 371
Conference Proceedings Title: Proceedings of Science
Event location: Swakopmund
Abstract
High-redshift blazars (z ≥ 2.5) are the most powerful class of persistent γ-ray sources in the Universe. These objects possess the highest jet powers and luminosities and have black hole masses often in excess of 109 solar masses. In addition, high-z blazars are important cosmological probes and serve as test objects for blazar evolution models. Due to their large distance and the resulting electron/positron cascading on the extragalactic background light, their high-energy emission typically peaks below the GeV range. This makes these blazars difficult to study with Fermi/LAT and only the very brightest objects are detectable. Hence, only a small number of high-z blazars could be detected with Fermi/LAT so far. In this work, we present a strategy to increase the detection statistics at redshift z ≥ 2.5 via a search for flaring events in high-z γ-ray blazars whose long-term averaged flux is just below the sensitivity limit of Fermi/LAT. Seven previously GeV undetected high-z blazars have been identified with a test statistic of TS ≥ 25 from their bright monthly outburst periods, while more detections are expected in the future.
Authors with CRIS profile
Involved external institutions
Noordwes-Universiteit / North-West University
South Africa (ZA)
Julius-Maximilians-Universität Würzburg
Germany (DE)
National Aeronautics and Space Administration (NASA)
United States (USA) (US)
Pennsylvania State University (Penn State)
United States (USA) (US)
South Africa (ZA)
Julius-Maximilians-Universität Würzburg
Germany (DE)
National Aeronautics and Space Administration (NASA)
United States (USA) (US)
Pennsylvania State University (Penn State)
United States (USA) (US)
How to cite
APA:
Kreter, M., Gokus, A., Kadler, M., Krauß, F., Buson, S., Ojha, R.,... Böttcher, M. (2019). Search for high-redshift blazars with Fermi/LAT. In Proceedings of Science. Swakopmund, NA: Sissa Medialab Srl.
MLA:
Kreter, Michael, et al. "Search for high-redshift blazars with Fermi/LAT." Proceedings of the 7th Annual Conference on High Energy Astrophysics in Southern Africa, HEASA 2019, Swakopmund Sissa Medialab Srl, 2019.
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