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Title: A SEARCH FOR FAST X-RAY VARIABILITY FROM ACTIVE GALACTIC NUCLEI USING SWIFT

Abstract

Blazars are a class of active galactic nuclei (AGNs) known for their very rapid variabilty in the high energy regions of the electromagnetic spectrum. Despite this known fast variability, X-ray observations have generally not revealed variability in blazars with rate doubling or halving timescales less than approximately 15 minutes. Since its launch, the Swift X-ray Telescope has obtained 0.2–10 keV X-ray data on 143 AGNs, including blazars, through intense target of opportunity observations that can be analyzed in a multiwavelength context and used to model jet parameters, particularly during flare states. We have analyzed this broad Swift data set in a search for short timescale variability in blazars that could limit the size of the emission region in the blazar jet. While we do find several low-significance possible flares with potential indications of rapid variability, we find no strong evidence for rapid (<15 minutes) doubling or halving times in flares in the soft X-ray energy band for the AGNs analyzed.

Authors:
; ;  [1]
  1. Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)
Publication Date:
OSTI Identifier:
22522542
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 802; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; GALAXIES; GALAXY NUCLEI; GAMMA RADIATION; JETS; KEV RANGE; PHOTON EMISSION; POTENTIALS; QUASARS; SOFT X RADIATION; STELLAR FLARES; TELESCOPES

Citation Formats

Pryal, Matthew, Falcone, Abe, and Stroh, Michael. A SEARCH FOR FAST X-RAY VARIABILITY FROM ACTIVE GALACTIC NUCLEI USING SWIFT. United States: N. p., 2015. Web. doi:10.1088/0004-637X/802/1/33.
Pryal, Matthew, Falcone, Abe, & Stroh, Michael. A SEARCH FOR FAST X-RAY VARIABILITY FROM ACTIVE GALACTIC NUCLEI USING SWIFT. United States. doi:10.1088/0004-637X/802/1/33.
Pryal, Matthew, Falcone, Abe, and Stroh, Michael. Fri . "A SEARCH FOR FAST X-RAY VARIABILITY FROM ACTIVE GALACTIC NUCLEI USING SWIFT". United States. doi:10.1088/0004-637X/802/1/33.
@article{osti_22522542,
title = {A SEARCH FOR FAST X-RAY VARIABILITY FROM ACTIVE GALACTIC NUCLEI USING SWIFT},
author = {Pryal, Matthew and Falcone, Abe and Stroh, Michael},
abstractNote = {Blazars are a class of active galactic nuclei (AGNs) known for their very rapid variabilty in the high energy regions of the electromagnetic spectrum. Despite this known fast variability, X-ray observations have generally not revealed variability in blazars with rate doubling or halving timescales less than approximately 15 minutes. Since its launch, the Swift X-ray Telescope has obtained 0.2–10 keV X-ray data on 143 AGNs, including blazars, through intense target of opportunity observations that can be analyzed in a multiwavelength context and used to model jet parameters, particularly during flare states. We have analyzed this broad Swift data set in a search for short timescale variability in blazars that could limit the size of the emission region in the blazar jet. While we do find several low-significance possible flares with potential indications of rapid variability, we find no strong evidence for rapid (<15 minutes) doubling or halving times in flares in the soft X-ray energy band for the AGNs analyzed.},
doi = {10.1088/0004-637X/802/1/33},
journal = {Astrophysical Journal},
number = 1,
volume = 802,
place = {United States},
year = {Fri Mar 20 00:00:00 EDT 2015},
month = {Fri Mar 20 00:00:00 EDT 2015}
}