Deep Broadband Observations of the Distant GAMMA-RAY Blazar PKS 1424+240

  title={Deep Broadband Observations of the Distant GAMMA-RAY Blazar PKS 1424+240},
  author={S. Archambault and T. Aune and B. Behera and M. Beilicke and W. Benbow and K. Berger and R. Bird and J. Biteau and V. Bugaev and K. Byrum and J. Cardenzana and M. Cerruti and X. Chen and L. Ciupik and M. P. Connolly and W. Cui and J. Dumm and M. Errando and A. Falcone and S. Federici and Q. Feng and J. Finley and H. Fleischhack and L. Fortson and A. Furniss and N. Galante and G. Gillanders and S. Griffin and S. Griffiths and J. Grube and G. Gyuk and D. Hanna and J. Holder and G. Hughes and T. Humensky and C. Johnson and P. Kaaret and M. Kertzman and Y. Khassen and D. Kieda and H. Krawczynski and F. Krennrich and S. Kumar and M. Lang and A. Madhavan and G. Maier and A. McCann and K. Meagher and P. Moriarty and R. Mukherjee and D. Nieto and A. O. D. Bhr{\'o}ithe and R. Ong and A. N. Otte and N. Park and M. Pohl and A. Popkow and H. Prokoph and J. Quinn and K. Ragan and J. Rajotte and L. Reyes and P. Reynolds and G. Richards and E. Roache and G. Sembroski and K. Shahinyan and D. Staszak and I. Telezhinsky and J. Tucci and J. Tyler and A. Varlotta and V. Vassiliev and S. Vincent and S. Wakely and A. Weinstein and R. Welsing and A. Wilhelm and D. Williams and M. Ackermann and M. Ajello and A. Albert and L. Baldini and D. Bastieri and R. Bellazzini and E. Bissaldi and J. Bregeon and R. Buehler and S. Buson and G. Caliandro and R. Cameron and P. Caraveo and E. Cavazzuti and E. Charles and J. Chiang and S. Ciprini and R. Claus and S. Cutini and F. D’Ammando and A. Angelis and F. Palma and C. Dermer and S. Digel and L. Venere and P. Drell and C. Favuzzi and A. Franckowiak and P. Fusco and F. Gargano and D. Gasparrini and N. Giglietto and F. Giordano and M. Giroletti and I. Grenier and S. Guiriec and T. Jogler and M. Kuss and S. Larsson and L. Latronico and F. Longo and F. Loparco and P. Lubrano and G. Madejski and M. Mayer and M. Mazziotta and P. Michelson and T. Mizuno and M. Monzani and A. Morselli and S. Murgia and E. Nuss and T. Ohsugi and J. Ormes and J. Perkins and F. Piron and G. Pivato and S. Rain{\`o} and M. Razzano and A. Reimer and O. Reimer and S. Ritz and M. Schaal and C. Sgr{\`o} and E. Siskind and P. Spinelli and H. Takahashi and L. Tibaldo and M. Tinivella and E. Troja and G. Vianello and M. Werner and M. Wood},
  journal={The Astrophysical Journal},
We present deep VERITAS observations of the blazar PKS 1424+240, along with contemporaneous Fermi Large Area Telescope, Swift X-ray Telescope, and Swift UV Optical Telescope data between 2009 February 19 and 2013 June 8. This blazar resides at a redshift of z ≥ 0.6035, displaying a significantly attenuated gamma-ray flux above 100 GeV due to photon absorption via pair-production with the extragalactic background light. We present more than 100 hr of VERITAS observations over three years, a… Expand
MAGIC long-term study of the distant TeV blazar PKS 1424+240 in a multiwavelength context
Aims. We present a study of the very high energy (VHE; E>100 GeV) -ray emission of the blazar PKS 1424+240 observed with the MAGIC telescopes. The primary aim of this paper is the multiwavelengthExpand
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We report the first detection of very-high-energy (VHE) gamma-ray emission above 140 GeV from PKS 1424+240, a BL Lac object with an unknown redshift. The photon spectrum above 140 GeV measured byExpand
We present the redshift lower limit of z ≥ 0.6035 for the very high energy (VHE; E ≥ 100 GeV) emitting blazar PKS 1424+240 (PG 1424+240). This limit is inferred from Lyβ and Lyγ absorption observedExpand
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Lower limits on the power emitted in ultrahigh-energy cosmic rays (UHECRs), which are assumed to be protons with energy 1017-1020 eV, are derived for TeV blazars with the assumption that the observedExpand
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An absorption feature seen in the combined spectra of a sample of gamma-ray blazars out to a redshift of z ∼ 1.6 allowed us to measure the EBL flux density in this frequency band and put constraints on the cosmic history of star formation. Expand