A three-year multi-wavelength study of the very-high-energy γ-ray blazar 1ES 0229+200

Journal Article · Mon Feb 10 04:00:00 EST 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/782/1/13· OSTI ID:22348064

Aliu, E. ^[1]; Archambault, S. ^[2]; Arlen, T.; Aune, T. ^[3]; Behera, B.; Chen, X. ^[4]; Beilicke, M.; Buckley, J. H.; Bugaev, V. ^[5]; Benbow, W.; Cerruti, M. ^[6]; Berger, K. ^[7]; Bird, R. ^[8]; Bouvier, A. ^[9]; Byrum, K. ^[10]; Ciupik, L. ^[11]; Connolly, M. P. ^[12]; Cui, W. ^[13]; Duke, C. ^[14]; others, and

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1. Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027 (United States)
2. Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada)
3. Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)
4. DESY, Platanenallee 6, D-15738 Zeuthen (Germany)
5. Department of Physics, Washington University, St. Louis, MO 63130 (United States)
6. Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States)
7. Department of Physics and Astronomy and the Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)
8. School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)
9. Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 (United States)
10. Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)
11. Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States)
12. School of Physics, National University of Ireland Galway, University Road, Galway (Ireland)
13. Department of Physics, Purdue University, West Lafayette, IN 47907 (United States)
14. Department of Physics, Grinnell College, Grinnell, IA 50112-1690 (United States)

The high-frequency-peaked BL Lacertae object 1ES 0229+200 is a relatively distant (z = 0.1396), hard-spectrum (Γ ∼ 2.5), very-high-energy (VHE; E > 100 GeV) emitting γ-ray blazar. VHE measurements of this active galactic nucleus have been used to place constraints on the intensity of the extragalactic background light and the intergalactic magnetic field (IGMF). A multi-wavelength study of this object centered around VHE observations by Very Energetic Radiation Imaging Telescope Array System (VERITAS) is presented. This study obtained, over a period of three years, an 11.7 standard deviation detection and an average integral flux F(E > 300 GeV) = (23.3 ± 2.8{sub stat} ± 5.8{sub sys}) × 10{sup –9} photons m{sup –2} s{sup –1}, or 1.7% of the Crab Nebula's flux (assuming the Crab Nebula spectrum measured by H.E.S.S). Supporting observations from Swift and RXTE are analyzed. The Swift observations are combined with previously published Fermi observations and the VHE measurements to produce an overall spectral energy distribution which is then modeled assuming one-zone synchrotron-self-Compton emission. The χ{sup 2} probability of the TeV flux being constant is 1.6%. This, when considered in combination with measured variability in the X-ray band, and the demonstrated variability of many TeV blazars, suggests that the use of blazars such as 1ES 0229+200 for IGMF studies may not be straightforward and challenges models that attribute hard TeV spectra to secondary γ-ray production along the line of sight.

• OSTI ID: 22348064
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 782; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BL LACERTAE OBJECTS
CRAB NEBULA
DETECTION
EMISSION
ENERGY SPECTRA
GALAXIES
GAMMA RADIATION
GEV RANGE
LIMITING VALUES
MAGNETIC FIELDS
SYNCHROTRONS
TELESCOPES
TEV RANGE
VISIBLE RADIATION
WAVELENGTHS
X RADIATION