TY - JOUR A1 - Archambault, S. A1 - Arlen, T. A1 - Aune, T. A1 - Behera, B. A1 - Beilicke, M. A1 - Benbow, W. A1 - Bird, R. A1 - Bouvier, A. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cesarini, A. A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gall, D. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Gyuk, G. A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Kaaret, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krawczynski, H. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - Majumdar, P. A1 - McArthur, S. A1 - McCann, A. A1 - Millis, J. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - de Bhroithe, A. O'Faolain A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Perkins, J. S. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Quinn, J. A1 - Ragan, K. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Saxon, D. B. A1 - Sembroski, G. H. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Theiling, M. A1 - Varlotta, A. A1 - Vassiliev, V. V. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weekes, T. C. A1 - Weinstein, A. A1 - Welsing, R. A1 - Williams, D. A. A1 - Zitzer, B. A1 - Boettcher, Markus A1 - Fegan, S. J. A1 - Fortin, P. A1 - Halpern, J. P. A1 - Kovalev, Y. Y. A1 - Lister, M. L. A1 - Liu, J. A1 - Pushkarev, A. B. A1 - Smith, P. S. T1 - Discovery of a new tev Gamma-Ray source - VER J0521+211 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We report the detection of a new TeV gamma-ray source, VER J0521+211, based on observations made with the VERITAS imaging atmospheric Cherenkov Telescope Array. These observations were motivated by the discovery of a cluster of >30 GeV photons in the first year of Fermi Large Area Telescope observations. VER J0521+211 is relatively bright at TeV energies, with a mean photon flux of (1.93 +/- 0.13(stat) +/- 0.78(sys)) x 10(-11) cm(-2) s(-1) above 0.2 TeV during the period of the VERITAS observations. The source is strongly variable on a daily timescale across all wavebands, from optical to TeV, with a peak flux corresponding to similar to 0.3 times the steady Crab Nebula flux at TeV energies. Follow-up observations in the optical and X-ray bands classify the newly discovered TeV source as a BL Lac-type blazar with uncertain redshift, although recent measurements suggest z = 0.108. VER J0521+211 exhibits all the defining properties of blazars in radio, optical, X-ray, and gamma-ray wavelengths. KW - BL Lacertae objects: individual (VER J0521+211) KW - gamma rays: galaxies Y1 - 2013 U6 - https://doi.org/10.1088/0004-637X/776/2/69 SN - 0004-637X SN - 1538-4357 VL - 776 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Aliu, E. A1 - Archambault, S. A1 - Behera, B. A1 - Berger, K. A1 - Beilicke, M. A1 - Benbow, W. A1 - Bird, R. A1 - Bouvier, A. A1 - Bugaev, V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dumm, J. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Griffiths, S. T. A1 - Grube, J. A1 - Gyuk, G. A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Kaaret, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Maier, G. A1 - Majumdar, P. A1 - McArthur, S. A1 - McCann, A. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - de Bhroithe, A. O'Faolain A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Perkins, J. S. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Quinn, J. A1 - Ragan, K. A1 - Rajotte, J. A1 - Ratliff, G. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Sembroski, G. H. A1 - Sheidaei, F. A1 - Skole, C. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tyler, J. A1 - Varlotta, A. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weekes, T. C. A1 - Weinstein, A. A1 - Welsing, R. A1 - Zajczyk, A. A1 - Zitzer, B. T1 - Multiwavelemght oservatons of the TeV binary LS I+61 degrees 303 with veritas, fermi-lat, and swift/XRT during a TeV outburst JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We present the results of a multiwavelength observational campaign on the TeV binary system LS I +61 degrees 303 with the VERITAS telescope array (>200 GeV), Fermi-LAT (0.3-300 GeV), and Swift/XRT (2-10 keV). The data were taken from 2011 December through 2012 January and show a strong detection in all three wavebands. During this period VERITAS obtained 24.9 hr of quality selected livetime data in which LS I +61 degrees 303 was detected at a statistical significance of 11.9 sigma. These TeV observations show evidence for nightly variability in the TeV regime at a post-trial significance of 3.6 sigma. The combination of the simultaneously obtained TeV and X-ray fluxes do not demonstrate any evidence for a correlation between emission in the two bands. For the first time since the launch of the Fermi satellite in 2008, this TeV detection allows the construction of a detailed MeV-TeV spectral energy distribution from LS I +61 degrees 303. This spectrum shows a distinct cutoff in emission near 4 GeV, with emission seen by the VERITAS observations following a simple power-law above 200 GeV. This feature in the spectrum of LS I +61 degrees 303, obtained from overlapping observations with Fermi-LAT and VERITAS, may indicate that there are two distinct populations of accelerated particles producing the GeV and TeV emission. KW - acceleration of particles KW - binaries: general KW - gamma rays: stars KW - relativistic processes KW - X-rays: binaries Y1 - 2013 U6 - https://doi.org/10.1088/0004-637X/779/1/88 SN - 0004-637X SN - 1538-4357 VL - 779 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Archambault, S. A1 - Beilicke, M. A1 - Benbow, W. A1 - Berger, K. A1 - Bird, R. A1 - Bouvier, A. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Duke, C. A1 - Dumm, J. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Griffiths, S. T. A1 - Grube, J. A1 - Gyuk, G. A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Kaaret, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krawczynski, H. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - Majumdar, P. A1 - McArthur, S. A1 - McCann, A. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - de Bhroithe, A. O'Faolain A1 - Ong, R. A. A1 - Otte, A. N. A1 - Pandel, D. A1 - Park, N. A1 - Perkins, J. S. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Quinn, J. A1 - Ragan, K. A1 - Rajotte, J. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Sembroski, G. H. A1 - Sheidaei, F. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Theiling, M. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Varlotta, A. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weekes, T. C. A1 - Weinstein, A. A1 - Williams, D. A. A1 - Zitzer, B. A1 - McCollough, M. L. T1 - Veritas observatons of the microquasar cygnus X-3 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We report results from TeV gamma-ray observations of the microquasar Cygnus X-3. The observations were made with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) over a time period from 2007 June 11 to 2011 November 28. VERITAS is most sensitive to gamma rays at energies between 85 GeV and 30 TeV. The effective exposure time amounts to a total of about 44 hr, with the observations covering six distinct radio/X-ray states of the object. No significant TeV gamma-ray emission was detected in any of the states, nor with all observations combined. The lack of a positive signal, especially in the states where GeV gamma rays were detected, places constraints on TeV gamma-ray production in Cygnus X-3. We discuss the implications of the results. KW - acceleration of particles KW - binaries: close KW - gamma rays: stars KW - X-rays: individual (Cygnus X-3) Y1 - 2013 U6 - https://doi.org/10.1088/0004-637X/779/2/150 SN - 0004-637X SN - 1538-4357 VL - 779 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Aliu, E. A1 - Archambault, S. A1 - Arlen, T. A1 - Aune, T. A1 - Beilicke, M. A1 - Benbow, W. A1 - Bird, R. A1 - Bouvier, A. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Cesarini, A. A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dumm, J. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gerard, L. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Gyuk, G. A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Kaaret, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krawczynski, H. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - Majumdar, P. A1 - McArthur, S. A1 - McCann, A. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - De Bhroithe, A. O'Faolain A1 - Ong, R. A. A1 - Orr, M. A1 - Otte, A. N. A1 - Park, N. A1 - Perkins, J. S. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Quinn, J. A1 - Ragan, K. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Saxon, D. B. A1 - Sembroski, G. H. A1 - Skole, C. A1 - Smith, A. W. A1 - Soares-Furtado, M. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tesic, G. A1 - Theiling, M. A1 - Varlotta, A. A1 - Vassiliev, V. V. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weekes, T. C. A1 - Weinstein, A. A1 - Welsing, R. A1 - Williams, D. A. A1 - Zitzer, B. A1 - Böttcher, Markus A1 - Fumagalli, M. A1 - Jadhav, J. T1 - Long term observations of B2 1215+30 with veritas JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We report on VERITAS observations of the BL Lac object B2 1215+30 between 2008 and 2012. During this period, the source was detected at very high energies (VHEs; E > 100 GeV) by VERITAS with a significance of 8.9s and showed clear variability on timescales larger than months. In 2011, the source was found to be in a relatively bright state and a power-law fit to the differential photon spectrum yields a spectral index of 3.6 +/- 0.4(stat) +/- 0.3(syst) with an integral flux above 200 GeV of (8.0 +/- 0.9(stat) +/- 3.2(syst)) x 10(-12) cm(-2) s(-1). No short term variability could be detected during the bright state in 2011. Multi-wavelength data were obtained contemporaneously with the VERITAS observations in 2011 and cover optical (Super-LOTIS, MDM, Swift/UVOT), X-ray (Swift/XRT), and gamma-ray (Fermi-LAT) frequencies. These were used to construct the spectral energy distribution (SED) of B2 1215+30. A one-zone leptonic model is used to model the blazar emission and the results are compared to those of MAGIC from early 2011 and other VERITAS-detected blazars. The SED can be reproduced well with model parameters typical for VHE-detected BL Lac objects. KW - BL Lacertae objects: general KW - BL Lacertae objects: individual (B2 1215+30, VER J1217+301) Y1 - 2013 U6 - https://doi.org/10.1088/0004-637X/779/2/92 SN - 0004-637X SN - 1538-4357 VL - 779 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Aliu, E. A1 - Aune, T. A1 - Behera, B. A1 - Beilicke, M. A1 - Benbow, W. A1 - Berger, K. A1 - Bird, R. A1 - Bouvier, A. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dumm, J. A1 - Dwarkadas, Vikram V. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gillanders, G. H. A1 - Gotthelf, E. V. A1 - Griffin, S. A1 - Griffiths, S. T. A1 - Grube, J. A1 - Gyuk, G. A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kargaltsev, O. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Millis, J. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Pandel, D. A1 - Park, N. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Quinn, J. A1 - Ragan, K. A1 - Rajotte, J. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Roberts, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weinstein, A. A1 - Welsing, R. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. T1 - Spatially resolving the very high energy emission from MRGO J2019+37 wih veritas JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We present very high energy (VHE) imaging of MGRO J2019+37 obtained with the VERITAS observatory. The bright extended (similar to 2 degrees) unidentified Milagro source is located toward the rich star formation region Cygnus-X. MGRO J2019+37 is resolved into two VERITAS sources. The faint, point-like source VER J2016+371 overlaps CTB 87, a filled-center remnant (SNR) with no evidence of a supernova remnant shell at the present time. Its spectrum is well fit in the 0.65-10 TeV energy range by a power-law model with photon index 2.3 +/- 0.4. VER J2019+378 is a bright extended (similar to 1 degrees) source that likely accounts for the bulk of the Milagro emission and is notably coincident with PSR J2021+3651 and the star formation region Sh 2-104. Its spectrum in the range 1-30 TeV is well fit with a power-law model of photon index 1.75 +/- 0.3, among the hardest values measured in the VHE band, comparable to that observed near Vela-X. We explore the unusual spectrum and morphology in the radio and X-ray bands to constrain possible emission mechanisms for this source. KW - gamma rays : stars KW - pulsars : individual (PSR J2021+3651) KW - supernovae : individual (CTB 87) Y1 - 2014 U6 - https://doi.org/10.1088/0004-637X/788/1/78 SN - 0004-637X SN - 1538-4357 VL - 788 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Aliu, E. A1 - Archambault, S. A1 - Arlen, T. A1 - Aune, T. A1 - Beilicke, M. A1 - Benbow, W. A1 - Bird, R. A1 - Boettcher, Markus A1 - Bouvier, A. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cesarini, A. A1 - Ciupik, L. A1 - Collins-Hughes, E. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dickherber, R. A1 - Duke, C. A1 - Dumm, J. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Finnegan, G. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gall, D. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Gyuk, G. A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Kaaret, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krawczynski, H. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - Majumdar, P. A1 - McArthur, S. A1 - McCann, A. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nelson, T. A1 - de Bhroithe, A. O'Faolain A1 - Ong, R. A. A1 - Orr, M. A1 - Otte, A. N. A1 - Park, N. A1 - Perkins, J. S. A1 - Pichel, A. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Quinn, J. A1 - Ragan, K. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Roache, E. A1 - Saxon, D. B. A1 - Schroedter, M. A1 - Sembroski, G. H. A1 - Skole, C. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Theiling, M. A1 - Tyler, J. A1 - Varlotta, A. A1 - Vassiliev, V. V. A1 - Wakely, S. P. A1 - Weekes, T. C. A1 - Weinstein, A. A1 - Welsing, R. A1 - Williams, D. A. A1 - Zitzer, B. T1 - Multiwavelenght observations and modeling of 1ES 1959+650 in a low flux state JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We report on the VERITAS observations of the high-frequency peaked BL Lac object 1ES 1959+650 in the period 2007-2011. This source is detected at TeV energies by VERITAS at 16.4 standard deviation (sigma) significance in 7.6 hr of observation in a low flux state. A multiwavelength spectral energy distribution (SED) is constructed from contemporaneous data from VERITAS, Fermi-LAT, RXTE PCA, and Swift UVOT. Swift XRT data is not included in the SED due to a lack of simultaneous observations with VERITAS. In contrast to the orphan gamma-ray flare exhibited by this source in 2002, the X-ray flux of the source is found to vary by an order of magnitude, while other energy regimes exhibit less variable emission. A quasi-equilibrium synchrotron self-Compton model with an additional external radiation field is used to describe three SEDs corresponding to the lowest, highest, and average X-ray states. The variation in the X-ray spectrum is modeled by changing the electron injection spectral index, with minor adjustments of the kinetic luminosity in electrons. This scenario produces small-scale flux variability of the order of less than or similar to 2 in the high energy (E > 1MeV) and very high energy (E > 100 GeV) gamma-ray regimes, which is corroborated by the Fermi-LAT, VERITAS, and Whipple 10 m telescope light curves. KW - BL Lacertae objects: general KW - BL Lacertae objects: individual (1ES 1959+650=VER J1959+651) KW - galaxies: active KW - gamma rays: galaxies Y1 - 2013 U6 - https://doi.org/10.1088/0004-637X/775/1/3 SN - 0004-637X VL - 775 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Aliu, E. A1 - Archambault, S. A1 - Aune, T. A1 - Behera, B. A1 - Beilicke, M. A1 - Benbow, W. A1 - Berger, K. A1 - Bird, R. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Cardenzana, J. V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Ciupik, L. A1 - Collins-Hughes, E. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dumm, J. A1 - Dwarkadas, Vikram V. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gall, D. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Griffiths, S. T. A1 - Grube, J. A1 - Gyuk, G. A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Kaaret, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - McCann, A. J. A1 - Meagher, K. A1 - Millis, J. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Pandel, D. A1 - Park, N. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Quinn, J. A1 - Ragan, K. A1 - Rajotte, J. A1 - Ratliff, G. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Rousselle, J. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Sheidaei, F. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tsurusaki, K. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Varlotta, A. A1 - Vassiliev, V. V. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Ward, J. E. A1 - Weinstein, A. A1 - Welsing, R. A1 - Wilhelm, Alina T1 - Investigating the TeV morpholoy of MGRO J1908+06 with veritas JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We report on deep observations of the extended TeV gamma-ray source MGRO J1908+06 made with the VERITAS very high energy gamma-ray observatory. Previously, the TeV emission has been attributed to the pulsar wind nebula (PWN) of the Fermi-LAT pulsar PSR J1907+0602. We detect MGRO J1908+06 at a significance level of 14 standard deviations (14 sigma) and measure a photon index of 2.20 +/- 0.10(stat) +/- 0.20(sys). The TeV emission is extended, covering the region near PSR J1907+0602 and also extending toward SNR G40.5-0.5. When fitted with a two-dimensional Gaussian, the intrinsic extension has a standard deviation of sigma(src) = 0 degrees.44 +/- 0 degrees.02. In contrast to other TeV PWNe of similar age in which the TeV spectrum softens with distance from the pulsar, the TeV spectrum measured near the pulsar location is consistent with that measured at a position near the rim of G40.5-0.5, 0 degrees.33 away. KW - gamma rays: general KW - gamma-ray burst: individual (MGRO J1908+06, VER J1907+062) KW - pulsars: individual (PSR J1907+0602) KW - ISM: supernova remnants Y1 - 2014 U6 - https://doi.org/10.1088/0004-637X/787/2/166 SN - 0004-637X SN - 1538-4357 VL - 787 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Aliu, E. A1 - Aune, T. A1 - Barnacka, Anna A1 - Beilicke, M. A1 - Benbow, W. A1 - Berger, K. A1 - Biteau, Jonathan A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cardenzana, J. V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Ciupik, L. A1 - Connaughton, V. A1 - Cui, W. A1 - Dickinson, H. J. A1 - Eisch, J. D. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Galante, N. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Griffiths, S. T. A1 - Grube, J. A1 - Gyuk, G. A1 - Hakansson, Nils A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krawczynski, H. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Millis, J. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Rajotte, J. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Varlotta, A. A1 - Vassiliev, V. V. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Welsing, R. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. A1 - McEnery, J. E. A1 - Perkins, J. S. A1 - Veres, P. A1 - Zhu, S. T1 - Constraints on very high energy emission from GRB 130427A JF - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters N2 - Prompt emission from the very fluent and nearby (z = 0.34) gamma-ray burst GRB130427A was detected by several orbiting telescopes and by ground-based, wide-field-of-view optical transient monitors. Apart from the intensity and proximity of this GRB, it is exceptional due to the extremely long-lived high-energy (100 MeV to 100 GeV) gamma-ray emission, which was detected by the Large Area Telescope on the Fermi Gamma-Ray Space Telescope for similar to 70 ks after the initial burst. The persistent, hard-spectrum, high-energy emission suggests that the highest-energy gamma rays may have been produced via synchrotron self-Compton processes though there is also evidence that the high-energy emission may instead be an extension of the synchrotron spectrum. VERITAS, a ground-based imaging atmospheric Cherenkov telescope array, began follow-up observations of GRB130427A similar to 71 ks (similar to 20 hr) after the onset of the burst. The GRB was not detected with VERITAS; however, the high elevation of the observations, coupled with the low redshift of the GRB, make VERITAS a very sensitive probe of the emission from GRB130427A for E > 100 GeV. The non-detection and consequent upper limit derived place constraints on the synchrotron self-Compton model of high-energy gamma-ray emission from this burst. KW - gamma-ray burst: individual (GRB 130427A) Y1 - 2014 U6 - https://doi.org/10.1088/2041-8205/795/1/L3 SN - 2041-8205 SN - 2041-8213 VL - 795 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Archambault, S. A1 - Archer, A. A1 - Benbow, W. A1 - Bird, R. A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Byrum, K. A1 - Cardenzana, J. V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Christiansen, J. L. A1 - Ciupik, L. A1 - Cui, W. A1 - Dickinson, H. J. A1 - Eisch, J. D. A1 - Errando, M. A1 - Falcone, A. A1 - Fegan, D. J. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Gyuk, G. A1 - Huetten, M. A1 - Hakansson, Nils A1 - Hanna, D. A1 - Holder, J. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Perkins, J. S. A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Ratliff, G. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Williams, D. A. A1 - Zitzer, B. T1 - A SEARCH FOR BRIEF OPTICAL FLASHES ASSOCIATED WITH THE SETI TARGET KIC 8462852 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters N2 - The F-type star KIC. 8462852 has recently been identified as an exceptional target for search for extraterrestrial intelligence (SETI) observations. We describe an analysis methodology for optical SETI, which we have used to analyze nine hours of serendipitous archival observations of KIC. 8462852 made with the VERITAS gamma-ray observatory between 2009 and 2015. No evidence of pulsed optical beacons, above a pulse intensity at the Earth of approximately 1 photon m(-2), is found. We also discuss the potential use of imaging atmospheric Cherenkov telescope arrays in searching for extremely short duration optical transients in general. KW - astrobiology KW - extraterrestrial intelligence KW - methods: observational KW - stars: individual ( KIC 8462852) KW - techniques: photometric Y1 - 2016 U6 - https://doi.org/10.3847/2041-8205/818/2/L33 SN - 2041-8205 SN - 2041-8213 VL - 818 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Archambault, S. A1 - Archer, A. A1 - Benbow, W. A1 - Bird, R. A1 - Biteau, Jonathan A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cardenzana, J. V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Christiansen, J. L. A1 - Ciupik, L. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dickinson, H. J. A1 - Dumm, J. A1 - Eisch, J. D. A1 - Errando, M. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Flinders, A. A1 - Fortin, P. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Gyuk, G. A1 - Huetten, M. A1 - Hanna, D. A1 - Holder, J. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Pelassa, V. A1 - Petrashyk, A. A1 - Petry, D. A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Ratliff, G. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Reynolds, K. A1 - Richards, G. T. A1 - Roache, E. A1 - Rulten, C. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Smith, A. W. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Vincent, S. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. T1 - VERITAS and multiwavelength observations of the BL Lacertae object 1ES 1741+196 JF - Monthly notices of the Royal Astronomical Society N2 - We present results from multiwavelength observations of the BL Lacertae object 1ES 1741 + 196, including results in the very high energy gamma-ray regime using the Very Energetic Radiation Imaging Telescope Array System (VERITAS). The VERITAS time-averaged spectrum, measured above 180 GeV, is well modelled by a power law with a spectral index of 2.7 +/- 0.7(stat) +/- 0.2(syst). The integral flux above 180 GeV is (3.9 +/- 0.8(stat) +/- 1.0(syst)) x 10(-8) m(-2) s(-1), corresponding to 1.6 per cent of the Crab nebula flux on average. The multiwavelength spectral energy distribution of the source suggests that 1ES 1741+196 is an extreme-high-frequency-peaked BL Lacertae object. The observations analysed in this paper extend over a period of six years, during which time no strong flares were observed in any band. This analysis is therefore one of the few characterizations of a blazar in a non-flaring state. KW - astroparticle physics KW - relativistic processes KW - galaxies: individual: 1ES 1741+196=VER J1744+195 Y1 - 2016 U6 - https://doi.org/10.1093/mnras/stw664 SN - 0035-8711 SN - 1365-2966 VL - 459 SP - 2550 EP - 2557 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Benbow, W. A1 - Bird, R. A1 - Brill, A. A1 - Brose, Robert A1 - Chromey, A. J. A1 - Daniel, M. K. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Giuri, C. A1 - Gueta, O. A1 - Hanna, D. A1 - Halpern, J. P. A1 - Hassan, Tarek A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Joyce, Amy M. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - Maier, Gernot A1 - Matthews, N. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Nievas-Rosillos, M. A1 - Ong, R. A. A1 - Park, N. A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Pueschel, Elisa A1 - Quinn, John A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Rulten, C. A1 - Sadeh, Iftach A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Sushch, Iurii A1 - Wakely, S. P. A1 - Wells, R. M. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, David A. A1 - Williamson, T. J. T1 - Direct measurement of stellar angular diameters by the VERITAS Cherenkov telescopes JF - Nature astronomy N2 - The angular size of a star is a critical factor in determining its basic properties1. Direct measurement of stellar angular diameters is difficult: at interstellar distances stars are generally too small to resolve by any individual imaging telescope. This fundamental limitation can be overcome by studying the diffraction pattern in the shadow cast when an asteroid occults a star2, but only when the photometric uncertainty is smaller than the noise added by atmospheric scintillation3. Atmospheric Cherenkov telescopes used for particle astrophysics observations have not generally been exploited for optical astronomy due to the modest optical quality of the mirror surface. However, their large mirror area makes them well suited for such high-time-resolution precision photometry measurements4. Here we report two occultations of stars observed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS)5 Cherenkov telescopes with millisecond sampling, from which we are able to provide a direct measurement of the occulted stars’ angular diameter at the ≤0.1 mas scale. This is a resolution never achieved before with optical measurements and represents an order of magnitude improvement over the equivalent lunar occultation method6. We compare the resulting stellar radius with empirically derived estimates from temperature and brightness measurements, confirming the latter can be biased for stars with ambiguous stellar classifications. Y1 - 2019 U6 - https://doi.org/10.1038/s41550-019-0741-z SN - 2397-3366 VL - 3 IS - 6 SP - 511 EP - 516 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Archambault, S. A1 - Archer, A. A1 - Benbow, W. A1 - Bird, R. A1 - Brose, Robert A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Cerruti, M. A1 - Connolly, M. P. A1 - Cui, W. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Huetten, M. A1 - Hanna, D. A1 - Hervet, O. A1 - Holder, J. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Maier, G. A1 - McArthur, S. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Rulten, C. A1 - Sadeh, I. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tyler, J. A1 - Vassiliev, V. V. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. T1 - Discovery of Very-high-energy Emission from RGB J2243+203 and Derivation of Its Redshift Upper Limit JF - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Supplement series N2 - Very-high-energy (VHE; > 100 GeV) gamma-ray emission from the blazar RGB J2243+203 was discovered with the VERITAS Cherenkov telescope array, during the period between 2014 December 21 and 24. The VERITAS energy spectrum from this source can be fitted by a power law with a photon index of 4.6 +/- 0.5, and a flux normalization at 0.15 TeV of (6.3 +/- 1.1) x 10(-10) cm(-2) s(-1) TeV-1. The integrated Fermi-LAT flux from 1 to 100 GeV during the VERITAS detection is (4.1 +/- 0.8) x 10(-8) cm(-2) s(-1), which is an order of magnitude larger than the four-year-averaged flux in the same energy range reported in the 3FGL catalog, (4.0 +/- 0.1 x 10(-9) cm(-2) s(-1)). The detection with VERITAS triggered observations in the X-ray band with the Swift-XRT. However, due to scheduling constraints Swift-XRT observations were performed 67 hr after the VERITAS detection, rather than simultaneously with the VERITAS observations. The observed X-ray energy spectrum between 2 and 10 keV can be fitted with a power law with a spectral index of 2.7 +/- 0.2, and the integrated photon flux in the same energy band is (3.6 +/- 0.6) x 10(-13) cm(-2) s(-1). EBL-model-dependent upper limits of the blazar redshift have been derived. Depending on the EBL model used, the upper limit varies in the range from z < 0.9 to z < 1.1. KW - galaxies: individual (RGB J2243+203) Y1 - 2017 U6 - https://doi.org/10.3847/1538-4365/aa8d76 SN - 0067-0049 SN - 1538-4365 VL - 233 SP - 1188 EP - 1204 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Archer, A. A1 - Benbow, W. A1 - Bird, R. A1 - Brose, Robert A1 - Buchovecky, M. A1 - Bugaev, V. A1 - Connolly, M. P. A1 - Cui, W. A1 - Daniel, M. K. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortson, L. A1 - Furniss, A. A1 - Hanna, D. A1 - Hervet, O. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Hutten, M. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kelley-Hoskins, N. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Maier, G. A1 - McArthur, S. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Rulten, C. A1 - Sadeh, I. A1 - Tyler, J. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Wissel, S. A. A1 - Zitzer, B. T1 - Measurement of the iron spectrum in cosmic rays by VERITAS JF - Physical review : D, Particles, fields, gravitation, and cosmology N2 - We present a new measurement of the energy spectrum of iron nuclei in cosmic rays from 20 TeV to 500 TeV; The measurement makes use of a template-based analysis method, which, for the first time, is applied to the energy reconstruction of iron-induced air showers recorded by the VERITAS array of imaging atmospheric Cherenkov telescopes. The event selection makes use of the direct Cherenkov light which is emitted by charged particles before the first interaction, as well as other parameters related to the shape of the recorded air shower images. The measured spectrum is well described by a power law dF/dE = f(0) center dot (E/E-0)(-gamma) over the full energy range, with gamma = 2.82 +/- 0.30(stat)(-0.27)(+0.24)(syst) and f(0) = (4.82 +/- 0.98(stat)(-2.70)(+2.12)(syst)) x 10(-7) m(-2) s(-1) TeV-1 sr(-1) at E-0 = 50 TeV, with no indication of a cutoff or spectral break. The measured differential flux is compatible with previous results, with improved statistical uncertainty at the highest energies. Y1 - 2018 U6 - https://doi.org/10.1103/PhysRevD.98.022009 SN - 2470-0010 SN - 2470-0029 VL - 98 IS - 2 PB - American Physical Society CY - College Park ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Archambault, S. A1 - Archer, A. A1 - Benbow, Wystan A1 - Bird, Ralph A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Byrum, K. A1 - Cerruti, M. A1 - Chen, X. A1 - Ciupik, L. A1 - Cui, W. A1 - Dickinson, H. J. A1 - Eisch, J. D. A1 - Errando, M. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Griffin, S. A1 - Grube, J. A1 - Hutten, M. A1 - Hakansson, N. A1 - Hanna, D. A1 - Holder, J. A1 - Humensky, T. B. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nguyen, T. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Pelassa, V. A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Rulten, C. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Fegan, S. A1 - Giebels, B. A1 - Horan, D. A1 - Berdyugin, A. A1 - Kuan, J. A1 - Lindfors, E. A1 - Nilsson, K. A1 - Oksanen, A. A1 - Prokoph, H. A1 - Reinthal, R. A1 - Takalo, L. A1 - Zefi, F. T1 - A Luminous and Isolated Gamma-Ray Flare from the Blazar B2 1215+30 JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - B2 1215+30 is a BL-Lac-type blazar that was first detected at TeV energies by the MAGIC atmospheric Cherenkov telescopes and subsequently confirmed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS) observatory with data collected between 2009 and 2012. In 2014 February 08, VERITAS detected a large-amplitude flare from B2. 1215+30 during routine monitoring observations of the blazar 1ES. 1218+304, located in the same field of view. The TeV flux reached 2.4 times the Crab Nebula flux with a variability timescale of <3.6 hr. Multiwavelength observations with Fermi-LAT, Swift, and the Tuorla Observatory revealed a correlated high GeV flux state and no significant optical counterpart to the flare, with a spectral energy distribution where the gamma-ray luminosity exceeds the synchrotron luminosity. When interpreted in the framework of a onezone leptonic model, the observed emission implies a high degree of beaming, with Doppler factor delta > 10, and an electron population with spectral index p < 2.3. KW - BL Lacertae objects: individual (B2 1215+30, VER J1217+301) KW - galaxies: active KW - galaxies: jets KW - galaxies: nuclei KW - gamma rays: galaxies Y1 - 2017 U6 - https://doi.org/10.3847/1538-4357/836/2/205 SN - 0004-637X SN - 1538-4357 VL - 836 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Archer, A. A1 - Benbow, Wystan A1 - Bird, Ralph A1 - Brose, Robert A1 - Buchovecky, M. A1 - Bugaev, V A1 - Cui, Wei A1 - Danie, M. K. A1 - Falcone, A. A1 - Feng, Qi A1 - Finley, John P. A1 - Flinders, A. A1 - Fortson, L. A1 - Furniss, Amy A1 - Gillanders, Gerard H. A1 - Huttens, M. A1 - Hanna, David A1 - Hervet, O. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Johnson, Caitlin A. A1 - Kaaret, Philip A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kieda, David A1 - Krause, Maria A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - McArthur, S. A1 - Moriarty, P. A1 - Mukherjee, Reshmi A1 - Nieto, Daniel A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, Nahee A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Popkow, Alexis A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynold, P. T. A1 - Richards, Gregory T. A1 - Roache, E. A1 - Rulten, C. A1 - Sadeh, I A1 - Sembroski, G. H. A1 - Shahinyan, Karlen A1 - Tyler, J. A1 - Wakely, S. P. A1 - Weiner, O. M. A1 - Weinstein, A. A1 - Wells, R. M. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, David A. A1 - Brisken, W. F. A1 - Pontrelli, P. T1 - HESS J1943+213 BT - An extreme blazar shining through the galactic plane JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - HESS J1943+213 is a very high energy (VHE; > 100 GeV) gamma-ray source in the direction of the Galactic plane. Studies exploring the classification of the source are converging toward its identification as an extreme synchrotron BL Lac object. Here we present 38 hr of VERITAS observations of HESS J1943+213 taken over 2 yr. The source is detected with a significance of similar to 20 standard deviations, showing a remarkably stable flux and spectrum in VHE gamma-rays. Multifrequency Very Long Baseline Array (VLBA) observations of the source confirm the extended, jet-like structure previously found in the 1.6 GHz band with the European VLBI Network and detect this component in the 4.6 and 7.3 GHz bands. The radio spectral indices of the core and the jet and the level of polarization derived from the VLBA observations are in a range typical for blazars. Data from VERITAS, Fermi-LAT, Swift-XRT, the FLWO 48 ' telescope, and archival infrared and hard X-ray observations are used to construct and model the spectral energy distribution (SED) of the source with a synchrotron self-Compton model. The well-measured gamma-ray peak of the SED with VERITAS and Fermi-LAT provides constraining upper limits on the source redshift. Possible contribution of secondary gamma-rays from ultra-high-energy cosmic-ray-initiated electromagnetic cascades to the gamma-ray emission is explored, finding that only a segment of the VHE spectrum can be accommodated with this process. A variability search is performed across X-ray and gamma-ray bands. No statistically significant flux or spectral variability is detected. KW - astroparticle physics KW - BL Lacertae objects: individual (HESS J1943+213, VER J1943+213) KW - galaxies: active KW - galaxies: jets KW - galaxies: nuclei KW - gamma rays: galaxies Y1 - 2018 U6 - https://doi.org/10.3847/1538-4357/aacbd0 SN - 0004-637X SN - 1538-4357 VL - 862 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Archambault, S. A1 - Archer, A. A1 - Barnacka, Anna A1 - Behera, B. A1 - Beilicke, M. A1 - Benbow, W. A1 - Berger, K. A1 - Bird, R. A1 - Böttcher, Markus A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Cardenzana, J. V. A1 - Cerruti, M. A1 - Chen, Xuhui A1 - Christiansen, J. L. A1 - Ciupik, L. A1 - Collins-Hughes, E. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dickinson, H. J. A1 - Dumm, J. A1 - Eisch, J. D. A1 - Errando, M. A1 - Falcone, A. A1 - Federici, Simone A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortson, L. A1 - Furniss, A. A1 - Gillanders, G. H. A1 - Godambe, S. A1 - Griffin, S. A1 - Griffiths, S. T. A1 - Grube, J. A1 - Gyuk, G. A1 - Hakansson, Nils A1 - Hanna, D. A1 - Holder, J. A1 - Hughes, G. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kertzman, M. A1 - Khassen, Y. A1 - Kieda, D. A1 - Krawczynski, H. A1 - Kumar, S. A1 - Lang, M. J. A1 - Madhavan, A. S. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Meagher, K. A1 - Millis, J. A1 - Moriarty, P. A1 - Nelson, T. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, N. A1 - Perkins, J. S. A1 - Pohl, Martin A1 - Popkow, A. A1 - Prokoph, H. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Rajotte, J. A1 - Reyes, L. C. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Smith, A. W. A1 - Staszak, D. A1 - Sweeney, K. A1 - Telezhinsky, Igor O. A1 - Tucci, J. V. A1 - Tyler, J. A1 - Varlotta, A. A1 - Vassiliev, V. V. A1 - Wakely, S. P. A1 - Welsing, R. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. T1 - Discovery of very high energy gamma rays from 1ES 1440+122 JF - Monthly notices of the Royal Astronomical Society KW - BL Lacertae objects: general KW - gamma-rays: general Y1 - 2016 U6 - https://doi.org/10.1093/mnras/stw1319 SN - 0035-8711 SN - 1365-2966 VL - 461 SP - 202 EP - 208 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Benbow, Wystan A1 - Bird, Ralph A1 - Brill, A. A1 - Brose, Robert A1 - Buckley, J. H. A1 - Chromey, A. J. A1 - Daniel, M. K. A1 - Falcone, A. A1 - Finley, J. P. A1 - Fortson, L. A1 - Furniss, Amy A1 - Gent, A. A1 - Gillanders, Gerald H. A1 - Hanna, David A1 - Hassan, T. A1 - Hervet, O. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Kaaret, Philip A1 - Kar, P. A1 - Kertzman, M. A1 - Kieda, David A1 - Krause, Maria A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - Maier, Gernot A1 - Moriarty, P. A1 - Mukherjee, Reshmi A1 - Ong, R. A. A1 - Otte, Adam Nepomuk A1 - Park, Nahee A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Richards, Gregory T. A1 - Roache, E. A1 - Sadeh, I. A1 - Santander, Marcos A1 - Schlenstedt, S. A1 - Sembroski, G. H. A1 - Sushch, Iurii A1 - Tyler, J. A1 - Vassiliev, V. V. A1 - Wakely, S. P. A1 - Weinstein, A. A1 - Wells, R. M. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, David A. A1 - Williamson, T. J. A1 - Zitzer, B. A1 - Acciari, V. A. A1 - Ansoldi, S. A1 - Antonelli, L. A. A1 - Engels, A. Arbet A1 - Baack, D. A1 - Babic, A. A1 - Banerjee, B. A1 - de Almeida, U. Barres A1 - Barrio, J. A. A1 - Becerra Gonzalez, Josefa A1 - Bednarek, Wlodek A1 - Bernardini, Elisa A1 - Berti, A. A1 - Besenrieder, J. A1 - Bhattacharyya, W. A1 - Bigongiari, C. A1 - Biland, A. A1 - Blanch, O. A1 - Bonnoli, G. A1 - Busetto, G. A1 - Carosi, R. A1 - Ceribella, G. A1 - Cikota, S. A1 - Colak, S. M. A1 - Colin, P. A1 - Colombo, E. A1 - Contreras, J. L. A1 - Cortina, J. A1 - Covino, S. A1 - Da Vela, P. A1 - Dazzi, F. A1 - De Angelis, A. A1 - De Lotto, B. A1 - Delfino, M. A1 - Delgado, J. A1 - Di Pierro, F. A1 - Do Souto Espinera, E. A1 - Dominguez, A. A1 - Prester, D. Dominis A1 - Dorner, D. A1 - Doro, M. A1 - Einecke, S. A1 - Elsaesser, D. A1 - Ramazani, V. Fallah A1 - Fattorini, A. A1 - Fernandez-Barral, A. A1 - Ferrara, G. A1 - Fidalgo, D. A1 - Foffano, L. A1 - Fonseca, M. V. A1 - Font, L. A1 - Fruck, C. A1 - Galindo, D. A1 - Gallozzi, S. A1 - Lopez, R. J. Garcia A1 - Garczarczyk, M. A1 - Gasparyan, S. A1 - Gaug, Markus A1 - Giammaria, P. A1 - Godinovic, N. A1 - Guberman, D. A1 - Hadasch, D. A1 - Hahn, A. A1 - Herrera, J. A1 - Hoang, J. A1 - Hrupec, D. A1 - Inoue, S. A1 - Ishio, K. A1 - Iwamura, Y. A1 - Kubo, H. A1 - Kushida, J. A1 - Kuvezdic, D. A1 - Lamastra, A. A1 - Lelas, D. A1 - Leone, Francesco A1 - Lindfors, E. A1 - Lombardi, S. A1 - Longo, Francesco A1 - Lopez, M. A1 - Lopez-Oramas, A. A1 - Machado de Oliveira Fraga, B. A1 - Maggio, C. A1 - Majumdar, P. A1 - Makariev, M. A1 - Mallamaci, M. A1 - Maneva, G. A1 - Manganaro, M. A1 - Mannheim, K. A1 - Maraschi, L. A1 - Mariotti, M. A1 - Martinez, M. A1 - Masuda, S. A1 - Mazin, D. A1 - Minev, M. A1 - Miranda, J. M. A1 - Mirzoyan, R. A1 - Molina, E. A1 - Moralejo, A. A1 - Moreno, V. A1 - Moretti, E. A1 - Munar-Adrover, Pere A1 - Neustroev, V. A1 - Niedzwiecki, Andrzej A1 - Rosillo, Mireia Nievas A1 - Nigro, C. A1 - Nilsson, Kari A1 - Ninci, D. A1 - Nishijima, K. A1 - Noda, K. A1 - Nogues, L. A1 - Noethe, M. A1 - Paiano, Simona A1 - Palacio, J. A1 - Paneque, D. A1 - Paoletti, R. A1 - Paredes, J. M. A1 - Pedaletti, G. A1 - Penil, P. A1 - Peresano, M. A1 - Persic, M. A1 - Moroni, P. G. Prada A1 - Prandini, E. A1 - Puljak, I. A1 - Garcia, J. R. A1 - Rhode, W. A1 - Ribo, Marc A1 - Rico, J. A1 - Righi, C. A1 - Rugliancich, A. A1 - Saha, Lab A1 - Sahakyan, Narek A1 - Saito, T. A1 - Satalecka, K. A1 - Schweizer, T. A1 - Sitarek, J. A1 - Snidaric, I. A1 - Sobczynska, D. A1 - Somero, A. A1 - Stamerra, A. A1 - Strzys, M. A1 - Suric, T. A1 - Tavecchio, Fabrizio A1 - Temnikov, P. A1 - Terzic, T. A1 - Teshima, M. A1 - Torres-Alba, N. A1 - Tsujimoto, S. A1 - van Scherpenberg, J. A1 - Vanzo, G. A1 - Vazquez Acosta, M. A1 - Vovk, I. A1 - Will, M. A1 - Zaric, D. T1 - Periastron Observations of TeV Gamma-Ray Emission from a Binary System with a 50-year Period JF - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters N2 - We report on observations of the pulsar/Be star binary system PSR J2032+4127/MT91 213 in the energy range between 100 GeV and 20 TeV with the Very Energetic Radiation Imaging Telescope Array and Major Atmospheric Gamma Imaging Cherenkov telescope arrays. The binary orbit has a period of approximately 50 years, with the most recent periastron occurring on 2017 November 13. Our observations span from 18 months prior to periastron to one month after. A new point-like gamma-ray source is detected, coincident with the location of PSR J2032+4127/MT91 213. The gamma-ray light curve and spectrum are well characterized over the periastron passage. The flux is variable over at least an order of magnitude, peaking at periastron, thus providing a firm association of the TeV source with the pulsar/Be star system. Observations prior to periastron show a cutoff in the spectrum at an energy around 0.5 TeV. This result adds a new member to the small population of known TeV binaries, and it identifies only the second source of this class in which the nature and properties of the compact object are firmly established. We compare the gamma-ray results with the light curve measured with the X-ray Telescope on board the Neil Gehrels Swift Observatory and with the predictions of recent theoretical models of the system. We conclude that significant revision of the models is required to explain the details of the emission that we have observed, and we discuss the relationship between the binary system and the overlapping steady extended source, TeV J2032+4130. KW - gamma rays: general KW - pulsars: individual (PSR J2032+4127, VER J2032+414, MAGIC J2032+4127) KW - stars: individual (MT91 213) KW - X-rays: binaries Y1 - 2018 U6 - https://doi.org/10.3847/2041-8213/aae70e SN - 2041-8205 SN - 2041-8213 VL - 867 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Archer, A. A1 - Benbow, Wystan A1 - Bird, Ralph A1 - Brose, Robert A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Chromey, A. J. A1 - Cui, Wei A1 - Falcone, A. A1 - Feng, Qi A1 - Finley, J. P. A1 - Fortson, Lucy A1 - Furniss, Amy A1 - Gent, A. A1 - Gueta, O. A1 - Hanna, David A1 - Hassan, T. A1 - Hervet, Olivier A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Johnson, Caitlin A. A1 - Kaaret, Philip A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, David A1 - Krennrich, F. A1 - Kumar, S. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - McCann, A. A1 - Moriarty, P. A1 - Mukherjee, Reshmi A1 - Ong, R. A. A1 - Otte, Adam Nepomuk A1 - Pandel, D. A1 - Park, N. A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Richards, Gregory T. A1 - Roache, E. A1 - Sadeh, I A1 - Santander, Marcos A1 - Scott, S. S. A1 - Sembroski, G. H. A1 - Shahinyan, Karlen A1 - Sushch, Iurii A1 - Tyler, J. A1 - Wakely, S. P. A1 - Weinstein, A. A1 - Wells, R. M. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Williamson, T. J. A1 - Zitzer, B. T1 - A Search for Pulsed Very High-energy Gamma-Rays from 13 Young Pulsars in Archival VERITAS Data JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - We conduct a search for periodic emission in the very high-energy (VHE) gamma-ray band (E > 100 GeV) from a total of 13 pulsars in an archival VERITAS data set with a total exposure of over 450 hr. The set of pulsars includes many of the brightest young gamma-ray pulsars visible in the Northern Hemisphere. The data analysis resulted in nondetections of pulsed VHE gamma-rays from each pulsar. Upper limits on a potential VHE gamma-ray flux are derived at the 95% confidence level above three energy thresholds using two methods. These are the first such searches for pulsed VHE emission from each of the pulsars, and the obtained limits constrain a possible flux component manifesting at VHEs as is seen for the Crab pulsar. KW - gamma rays: general KW - pulsars: general KW - stars: neutron Y1 - 2019 U6 - https://doi.org/10.3847/1538-4357/ab14f4 SN - 0004-637X SN - 1538-4357 VL - 876 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Archambault, S. A1 - Archer, A. A1 - Benbow, Wystan A1 - Bird, Ralph A1 - Bourbeau, E. A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Cerruti, M. A1 - Connolly, M. P. A1 - Cui, W. A1 - Dwarkadas, Vikram V. A1 - Errando, M. A1 - Falcone, A. A1 - Feng, Q. A1 - Finley, J. P. A1 - Fleischhack, H. A1 - Fortson, L. A1 - Furniss, A. A1 - Griffin, S. A1 - Huetten, M. A1 - Hanna, D. A1 - Holder, J. A1 - Johnson, C. A. A1 - Kaaret, P. A1 - Kar, P. A1 - Kelley-Hoskins, N. A1 - Kertzman, M. A1 - Kieda, D. A1 - Krause, M. A1 - Kumar, S. A1 - Lang, M. J. A1 - Maier, G. A1 - McArthur, S. A1 - McCann, A. A1 - Moriarty, P. A1 - Mukherjee, R. A1 - Nieto, D. A1 - Ong, R. A. A1 - Otte, A. N. A1 - Park, Nahee A1 - Pohl, Martin A1 - Popkow, A. A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, G. T. A1 - Roache, E. A1 - Sadeh, I. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, K. A1 - Slane, P. A1 - Staszak, D. A1 - Telezhinsky, Igor O. A1 - Trepanier, S. A1 - Tyler, J. A1 - Wakely, S. P. A1 - Weinstein, A. A1 - Weisgarber, T. A1 - Wilcox, P. A1 - Wilhelm, Alina A1 - Williams, D. A. A1 - Zitzer, B. T1 - Gamma-ray Observations of Tycho's Supernova Remnant with VERITAS and Fermi JF - The astrophysical journal : an international review of spectroscopy and astronomical physics KW - material KW - data behind figure Y1 - 2017 U6 - https://doi.org/10.3847/1538-4357/836/1/23 SN - 0004-637X SN - 1538-4357 VL - 836 IS - 1 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Abeysekara, A. U. A1 - Benbow, Wystan A1 - Bird, Ralph A1 - Brantseg, T. A1 - Brose, Robert A1 - Buchovecky, M. A1 - Buckley, J. H. A1 - Bugaev, V. A1 - Connolly, M. P. A1 - Cui, Wei A1 - Daniel, M. K. A1 - Falcone, A. A1 - Feng, Qi A1 - Finley, John P. A1 - Fortson, L. A1 - Furniss, Amy A1 - Gillanders, Gerard H. A1 - Gunawardhana, Isuru A1 - Huetten, M. A1 - Hanna, David A1 - Hervet, O. A1 - Holder, J. A1 - Hughes, G. A1 - Humensky, T. B. A1 - Johnson, Caitlin A. A1 - Kaaret, Philip A1 - Kar, P. A1 - Kertzman, M. A1 - Krennrich, F. A1 - Lang, M. J. A1 - Lin, T. T. Y. A1 - McArthur, S. A1 - Moriarty, P. A1 - Mukherjee, Reshmi A1 - Ong, R. A. A1 - Otte, Adam Nepomuk A1 - Park, N. A1 - Petrashyk, A. A1 - Pohl, Martin A1 - Pueschel, Elisa A1 - Quinn, J. A1 - Ragan, K. A1 - Reynolds, P. T. A1 - Richards, Gregory T. A1 - Roache, E. A1 - Rulten, C. A1 - Sadeh, I. A1 - Santander, M. A1 - Sembroski, G. H. A1 - Shahinyan, Karlen A1 - Wakely, S. P. A1 - Weinstein, A. A1 - Wells, R. M. A1 - Wilcox, P. A1 - Williams, D. A. A1 - Zitzer, B. A1 - Jorstad, Svetlana G. A1 - Marscher, Alan P. A1 - Lister, Matthew L. A1 - Kovalev, Yuri Y. A1 - Pushkarev, A. B. A1 - Savolainen, Tuomas A1 - Agudo, I. A1 - Molina, S. N. A1 - Gomez, J. L. A1 - Larionov, Valeri M. A1 - Borman, G. A. A1 - Mokrushina, A. A. A1 - Tornikoski, Merja A1 - Lahteenmaki, A. A1 - Chamani, W. A1 - Enestam, S. A1 - Kiehlmann, S. A1 - Hovatta, Talvikki A1 - Smith, P. S. A1 - Pontrelli, P. T1 - Multiwavelength Observations of the Blazar BL Lacertae BT - a new Fast TeV Gamma-Ray Flare JF - The astrophysical journal : an international review of spectroscopy and astronomical physics N2 - Combined with measurements made by very-long-baseline interferometry, the observations of fast TeV gamma-ray flares probe the structure and emission mechanism of blazar jets. However, only a handful of such flares have been detected to date, and only within the last few years have these flares been observed from lower-frequency-peaked BL. Lac objects and flat-spectrum radio quasars. We report on a fast TeV gamma-ray flare from the blazar BL. Lacertae observed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS). with a rise time of similar to 2.3 hr and a decay time of similar to 36 min. The peak flux above 200 GeV is (4.2 +/- 0.6) x 10(-6) photon m(-2) s(-1) measured with a 4-minute-binned light curve, corresponding to similar to 180% of the flux that is observed from the Crab Nebula above the same energy threshold. Variability contemporaneous with the TeV gamma-ray flare was observed in GeV gamma-ray, X-ray, and optical flux, as well as in optical and radio polarization. Additionally, a possible moving emission feature with superluminal apparent velocity was identified in Very Long Baseline Array observations at 43 GHz, potentially passing the radio core of the jet around the time of the gamma-ray flare. We discuss the constraints on the size, Lorentz factor, and location of the emitting region of the flare, and the interpretations with several theoretical models that invoke relativistic plasma passing stationary shocks. KW - BL Lacertae objects: individual (BL Lacertae = VER J2202+422) KW - galaxies: active Y1 - 2018 U6 - https://doi.org/10.3847/1538-4357/aab35c SN - 0004-637X SN - 1538-4357 VL - 856 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER -