Multiwavelength Observations of the VHE Blazar 1ES 2344+514
Creators: name: Acciari, V. A.
name: Aliu, E.
name: Arlen, T.
name: Aune, T.
name: Beilicke, M.
name: Benbow, W.
name: Boltuch, D.
name: Bugaev, V.
name: Cannon, A.
name: Ciupik, L.
name: Cogan, P.
name: Colin, P.
name: Dickherber, R.
name: Falcone, A.
name: Fegan, S. J.
name: Finley, J. P.
name: Fortin, P.
name: Fortson, L. F.
name: Furniss, A.
name: Gall, D.
name: Gillanders, G. H.
name: Grube, J.
name: Guenette, R.
name: Gyuk, G.
name: Hanna, D.
name: Holder, J.
name: Horan, D.
name: Hui, C. M.
name: Humensky, T. B.
name: Imran, A.
name: Kaaret, P.
name: Karlsson, N.
name: Kertzman, M.
name: Kieda, D.
name: Kildea, J.
name: Konopelko, A.
name: Krawczynski, H.
name: Krennrich, F.
name: Lang, M. J.
name: LeBohec, S.
name: Maier, G.
name: Moriarty, P.
name: Mukherjee, R.
name: Ong, R. A.
name: Otte, A. N.
name: Pandel, D.
name: Perkins, J. S.
name: Pichel, A.
name: Pohl, M.
name: Quinn, J.
name: Ragan, K.
name: Reynolds, P. T.
name: Rose, H. J.
name: Schroedter, M.
name: Sembroski, G. H.
name: Smith, A. W.
name: Steele, D.
name: Swordy, S. P.
name: Theiling, M.
name: Toner, J. A.
name: Varlotta, A.
name: Vassiliev, V. V.
name: Vincent, S.
name: Wagner, R.
name: Wakely, S. P.
name: Ward, J. E.
name: Weekes, T. C.
name: Weinstein, A.
name: Weisgarber, T.
name: Williams, D. A.
name: Wissel, S.
name: Wood, M.
name: Zitzer, B.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Multiwavelength observations of the high-frequency-peaked blazar 1ES2344+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 &gt;100 GeV) γ-ray, X-ray, and UV energies. Observations with VERITAS in VHE γ-rays yield a strong detection of 20 σ with 633 excess events in a total exposure of 18.1 hours live-time. A strong VHE γ-ray flare on 2007 December 7 is measured at F(&gt;300 GeV) = (6.76 \pm 0.62) \times 10-11 ph 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(&gt;300 GeV) = (1.06 \pm 0.09) \times 10-11 ph 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 \pm 0.09stat \pm 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 XRT at a flux of F(2-10 keV) = (6.28 \pm 0.31) \times 10-11 erg cm-2 s-1. Evidence for a correlation between the X-ray flux and VHE γ-ray flux on nightly time-scales is indicated with a Pearson correlation coefficient of r = 0.60 \pm 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.
description: 13 pages, 7 figures, accepted by ApJ