Journal article
MULTIWAVELENGTH OBSERVATIONS OF THE VERY HIGH ENERGY BLAZAR 1ES 2344+514
The Astrophysical journal, Vol.738(2), 169
2011
DOI: 10.1088/0004-637X/738/2/169
Abstract
Multiwavelength observations of the high-frequency-peaked blazar 1ES 2344+514 were performed from 2007 October to 2008 January. The campaign represents the first contemporaneous data on the object at very high energy (VHE, E >100 GeV) γ-ray, X-ray, and UV energies. Observations with VERITAS in VHE γ-rays yield a strong detection of 20σ with 633 excess events in a total exposure of 18.1 hr live time. A strong VHE γ-ray flare on 2007 December 7 is measured at F(>300 GeV) = (6.76 ± 0.62) × 10−11 photons cm−2 s−1, corresponding to 48% of the Crab Nebula flux. Excluding this flaring episode, nightly variability at lower fluxes is observed with a time-averaged mean of F(>300 GeV) = (1.06 ± 0.09) × 10−11 photons cm−2 s−1 (7.6% of the Crab Nebula flux). The differential photon spectrum between 390 GeV and 8.3 TeV for the time-averaged observations excluding 2007 December 7 is well described by a power law with a photon index of Γ = 2.78 ± 0.09stat ± 0.15syst. On the flaring night of 2007 December 7 the measured VHE γ-ray photon index was Γ = 2.43 ± 0.22stat ± 0.15syst. Over the full period of VERITAS observations contemporaneous X-ray and UV data were taken with Swift and RXTE. The measured 2–10 keV flux ranged by a factor of ∼7 during the campaign. On 2007 December 8 the highest ever observed X-ray flux from 1ES 2344+514 was measured by Swift X-ray Telescope at a flux of F(2–10 keV) = (6.28 ± 0.31) × 10−11 erg cm−2 s−1. Evidence for a correlation between the X-ray flux and VHE γ-ray flux on nightly timescales is indicated with a Pearson correlation coefficient of r = 0.60 ± 0.11. Contemporaneous spectral energy distributions (SEDs) of 1ES 2344+514 are presented for two distinct flux states. A one-zone synchrotron self-Compton (SSC) model describes both SEDs using parameters consistent with previous SSC modeling of 1ES 2344+514 from non-contemporaneous observations.
Details
- Title: Subtitle
- MULTIWAVELENGTH OBSERVATIONS OF THE VERY HIGH ENERGY BLAZAR 1ES 2344+514
- Creators
- V. A Acciari - Harvard UniversityE Aliu - University of DelawareP Cogan - McGill UniversityP Colin - University of UtahR Dickherber - Washington University in St. LouisA Falcone - Pennsylvania State UniversityS. J Fegan - University of California, Los AngelesJ. P Finley - Purdue University West LafayetteP Fortin - Columbia UniversityL. F Fortson - Adler PlanetariumA Furniss - University of California, Santa CruzD Gall - Purdue University West LafayetteT Arlen - University of California, Los AngelesG. H Gillanders - Ollscoil na Gaillimhe – University of GalwayJ Grube - Adler PlanetariumR Guenette - McGill UniversityG Gyuk - Adler PlanetariumD Hanna - McGill UniversityJ Holder - University of DelawareD Horan - École PolytechniqueC. M Hui - University of UtahT. B Humensky - University of ChicagoA Imran - Iowa State UniversityT Aune - University of California, Santa CruzP Kaaret - University of IowaN Karlsson - Adler PlanetariumM Kertzman - DePauw UniversityD Kieda - University of UtahJ Kildea - Harvard UniversityA Konopelko - Pittsburg State UniversityH Krawczynski - Washington University in St. LouisF Krennrich - Iowa State UniversityM. J Lang - Ollscoil na Gaillimhe – University of GalwayS Lebohec - University of UtahM Beilicke - Washington University in St. LouisG Maier - McGill UniversityP Moriarty - Galway-Mayo Institute of TechnologyR Mukherjee - Columbia UniversityR. A Ong - University of California, Los AngelesA. N Otte - University of California, Santa CruzD Pandel - University of IowaJ. S Perkins - Harvard UniversityA Pichel - Universidad de Buenos AiresM Pohl - Iowa State UniversityJ Quinn - University College DublinW Benbow - Harvard UniversityK Ragan - McGill UniversityP. T Reynolds - Cork Institute of TechnologyH. J Rose - University of LeedsM Schroedter - Iowa State UniversityG. H Sembroski - Purdue University West LafayetteA. W Smith - Argonne National LaboratoryD Steele - Adler PlanetariumS. P Swordy - University of ChicagoM Theiling - Harvard UniversityJ. A Toner - Ollscoil na Gaillimhe – University of GalwayD Boltuch - University of DelawareV Bugaev - Washington University in St. LouisA Cannon - University College DublinL Ciupik - Adler Planetarium
- Resource Type
- Journal article
- Publication Details
- The Astrophysical journal, Vol.738(2), 169
- DOI
- 10.1088/0004-637X/738/2/169
- ISSN
- 0004-637X
- eISSN
- 1538-4357
- Publisher
- Institute of Physics (IOP)
- Language
- English
- Date published
- 2011
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9984199945102771
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