The variability of the blazar Markarian 421 in TeV gamma rays over a 14-year time period has been explored with the Whipple 10 m telescope. It is shown that the dynamic range of its flux variations is large and similar to that in X-rays. A correlation between the X-ray and TeV energy bands is observed during some bright flares and when the complete data sets are binned on long timescales. The main database consists of 878.4 h of observation with the Whipple telescope, spread over 783 nights. The peak energy response of the telescope was 400 GeV with 20% uncertainty. This is the largest database of any TeV-emitting active galactic nucleus (AGN) and hence was used to explore the variability profile of Markarian 421. The time-averaged flux from Markarian 421 over this period was 0.446±0.008 Crab flux units. The flux exceeded 10 Crab flux units on three separate occasions. For the 2000-2001 season the average flux reached 1.86 Crab units, while in the 1996-1997 season the average flux was only 0.23 Crab units. © 2013 Elsevier B.V. All rights reserved.
Documento: | Artículo |
Título: | Observation of Markarian 421 in TeV gamma rays over a 14-year time span |
Autor: | Acciari, V.A.; Arlen, T.; Aune, T.; Benbow, W.; Bird, R.; Bouvier, A.; Bradbury, S.M.; Buckley, J.H.; Bugaev, V.; De La Calle Perez, I.; Carter-Lewis, D.A.; Cesarini, A.; Ciupik, L.; Collins-Hughes, E.; Connolly, M.P.; Cui, W.; Duke, C.; Dumm, J.; Falcone, A.; Federici, S.; Fegan, D.J.; Fegan, S.J.; Finley, J.P.; Finnegan, G.; Fortson, L.; Gaidos, J.; Galante, N.; Gall, D.; Gibbs, K.; Gillanders, G.H.; Griffin, S.; Grube, J.; Gyuk, G.; Hanna, D.; Horan, D.; Humensky, T.B.; Kaaret, P.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krawczynski, H.; Krennrich, F.; Lang, M.J.; McEnery, J.E.; Madhavan, A.S.; Moriarty, P.; Nelson, T.; O'Faoláin De Bhróithe, A.; Ong, R.A.; Orr, M.; Otte, A.N.; Perkins, J.S.; Petry, D.; Pichel, A.; Pohl, M.; Quinn, J.; Ragan, K.; Reynolds, T.; Roache, E.; Rovero, A.; Schroedter, M.; Sembroski, G.H.; Smith, A.; Telezhinsky, I.; Theiling, M.; Toner, J.; Tyler, J.; Varlotta, A.; Vivier, M.; Wakely, S.P.; Ward, J.E.; Weekes, T.C.; Weinstein, A.; Welsing, R.; Williams, D.A.; Wissel, S. |
Filiación: | School of Science, Galway-Mayo Institute of Technology, Dublin Road, Galway, Ireland Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645, United States Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, United States Santa Cruz Institute for Particle Physics, Department of Physics, University of California, Santa Cruz, CA 95064, United States School of Physics, University College Dublin, Belfield, Dublin 4, Ireland Department of Physics, University of Leeds, Leeds LS2 9JT, Yorkshire, United Kingdom Department of Physics, Washington University, St. Louis, MO 63130, United States European Space Astronomy Center, 28080 Villafranca Del Castillo, Madrid, Spain Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, United States School of Physics, National University of Ireland Galway, University Road, Galway, Ireland Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605, United States Department of Physics, Purdue University, West Lafayette, IN 47907, United States Department of Physics, Grinnell College, Grinnell, IA 50112-1690, United States School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, United States Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802, United States Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany DESY, Platanenallee 6, 15738 Zeuthen, Germany Laboratoire Leprince-Riguet, École Polytechnique, CNRS/IN2P3, Palaiseau, France Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, United States Department of Physics and Astronomy, University of Iowa, Van Allen Hall, Iowa City, IA 52242, United States Physics Department, McGill University, Montreal, QC H3A 2T8, Canada Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027, United States Department of Physics and Astronomy, DePauw University, Greencastle, IN 46135-0037, United States NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States Department of Physics, University of Maryland, College Park, MD 20742, United States School of Physics, Center for Relativistic Astrophysics, Georgia Institute of Technology, 837 State Street NW, Atlanta, GA 30332-0430, United States CRESST, Astroparticle Physics Laboratory NASA/GSFC, Greenbelt, MD 20771, United States University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, United States ALMA Regional Centre, ESO, Karl-Schwarzschild-Strasse 2, 85748 Garching, Germany Instituto de Astronomía y Física Del Espacio, Casilla de Correo 67 - Sucursal 26 (C1428ZAA), Ciudad Autónoma de Buenos Aires, Argentina Department of Applied Physics and Instrumentation, Cork Institute of Technology, Cork, Ireland Department of Physics and Astronomy, Bartol Research Institute, University of Delaware, Newark, DE 19716, United States Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, United States Valeo Vision Systems, Tuam, Co., Galway, Ireland |
Palabras clave: | AGN; Markarian 421; TeV gamma rays; Active galactic nuclei; AGN; Average flux; Dynamic range; Flux variation; Markarian 421; Time-averaged; Time-periods; Gamma rays; Shellfish; Telescopes; Tellurium compounds |
Año: | 2014 |
Volumen: | 54 |
Página de inicio: | 1 |
Página de fin: | 10 |
DOI: | http://dx.doi.org/10.1016/j.astropartphys.2013.10.004 |
Título revista: | Astroparticle Physics |
Título revista abreviado: | Astropart. Phys. |
ISSN: | 09276505 |
CODEN: | APHYE |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_09276505_v54_n_p1_Acciari |