Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516
We report on the VERITAS discovery of very high energy (VHE) gamma-ray emission above 200GeV from the high-frequency-peaked BL Lac (HBL) object RXJ0648.7+1516 (GBJ0648+1516), associated with 1FGLJ0648.8+1516. The photon spectrum above 200GeV is fitted by a power law dN/dE = F 0(E/E 0)-Γ with a photo...
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2011
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paper:paper_0004637X_v742_n2_p_Aliu2023-06-08T14:29:03Z Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516 gamma rays: galaxies We report on the VERITAS discovery of very high energy (VHE) gamma-ray emission above 200GeV from the high-frequency-peaked BL Lac (HBL) object RXJ0648.7+1516 (GBJ0648+1516), associated with 1FGLJ0648.8+1516. The photon spectrum above 200GeV is fitted by a power law dN/dE = F 0(E/E 0)-Γ with a photon index Γ of 4.4 ± 0.8stat± 0.3syst and a flux normalization F 0 of (2.3± 0.5stat± 1.2sys) × 10-11TeV-1cm-2 s-1 with E 0 = 300GeV. No VHE variability is detected during VERITAS observations of RXJ0648.7+1516 between 2010 March 4 and April 15. Following the VHE discovery, the optical identification and spectroscopic redshift were obtained using the Shane 3 m Telescope at the Lick Observatory, showing the unidentified object to be a BL Lac type with a redshift of z = 0.179. Broadband multiwavelength observations contemporaneous with the VERITAS exposure period can be used to subclassify the blazar as an HBL object, including data from the MDM observatory, Swift-UVOT, and X-Ray Telescope, and continuous monitoring at photon energies above 1GeV from the Fermi Large Area Telescope (LAT). We find that in the absence of undetected, high-energy rapid variability, the one-zone synchrotron self-Compton (SSC) model overproduces the high-energy gamma-ray emission measured by the Fermi-LAT over 2.3 years. The spectral energy distribution can be parameterized satisfactorily with an external-Compton or lepto-hadronic model, which have two and six additional free parameters, respectively, compared to the one-zone SSC model. © 2011. The American Astronomical Society. All rights reserved. 2011 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v742_n2_p_Aliu http://hdl.handle.net/20.500.12110/paper_0004637X_v742_n2_p_Aliu |
institution |
Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
gamma rays: galaxies |
spellingShingle |
gamma rays: galaxies Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516 |
topic_facet |
gamma rays: galaxies |
description |
We report on the VERITAS discovery of very high energy (VHE) gamma-ray emission above 200GeV from the high-frequency-peaked BL Lac (HBL) object RXJ0648.7+1516 (GBJ0648+1516), associated with 1FGLJ0648.8+1516. The photon spectrum above 200GeV is fitted by a power law dN/dE = F 0(E/E 0)-Γ with a photon index Γ of 4.4 ± 0.8stat± 0.3syst and a flux normalization F 0 of (2.3± 0.5stat± 1.2sys) × 10-11TeV-1cm-2 s-1 with E 0 = 300GeV. No VHE variability is detected during VERITAS observations of RXJ0648.7+1516 between 2010 March 4 and April 15. Following the VHE discovery, the optical identification and spectroscopic redshift were obtained using the Shane 3 m Telescope at the Lick Observatory, showing the unidentified object to be a BL Lac type with a redshift of z = 0.179. Broadband multiwavelength observations contemporaneous with the VERITAS exposure period can be used to subclassify the blazar as an HBL object, including data from the MDM observatory, Swift-UVOT, and X-Ray Telescope, and continuous monitoring at photon energies above 1GeV from the Fermi Large Area Telescope (LAT). We find that in the absence of undetected, high-energy rapid variability, the one-zone synchrotron self-Compton (SSC) model overproduces the high-energy gamma-ray emission measured by the Fermi-LAT over 2.3 years. The spectral energy distribution can be parameterized satisfactorily with an external-Compton or lepto-hadronic model, which have two and six additional free parameters, respectively, compared to the one-zone SSC model. © 2011. The American Astronomical Society. All rights reserved. |
title |
Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516 |
title_short |
Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516 |
title_full |
Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516 |
title_fullStr |
Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516 |
title_full_unstemmed |
Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516 |
title_sort |
multiwavelength observations of the previously unidentified blazar rx j0648.7+1516 |
publishDate |
2011 |
url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v742_n2_p_Aliu http://hdl.handle.net/20.500.12110/paper_0004637X_v742_n2_p_Aliu |
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1768546656642400256 |