Browsing Research publications by Author "McHardy, I.M."

Now showing items 1-8 of 8

    • The 1993 multiwavelength campaign on 3C 279 : the radio to gamma-ray energy distribution inlow state 

      Maraschi, L.; Grandi, P.; Urry, C.M.; Wehrle, A. E.; Madejski, G.M.; Fink, H.; Ghisellini, G.; Hartman, R.C.; Koratkar, A.P.; von Montigny, C.; Pian, E.; Thomas, H.C.; Treves, A.; Aller, M. F.; Aller, H. D.; Bailyn, C. D.; Balonek, T.J.; Bock, H.; Collmar, W.; Glass, I.S.; Litchfield, S.J.; McHardy, I.M.; Mendez, R.; Pesce, J.; Reuter, H.-P.; Robson, E.I.; Steppe, H.; Stevens, Jason; Teraesranta, H.; Wagner, S.J. (1994-11-01)
      Simultaneous observations of 3C 279 at radio, millimeter, near-infrared, optical, ultraviolet (with IUE) and X-ray (with ROSAT) wavelengths were obtained in 1992 December-1993 January, during a three week pointing at the ...

    • 30 years of multi-wavelength observations of 3C 273 

      Turler, M.; Paltani, S.; Courvoisier, T. J-L.; Aller, M.; Aller, H.; Blecha, A.; Bouchet, P.; Lainela, M.; McHardy, I.M.; Robson, E.I.; Stevens, J. A.; Terasranta, H.; Tornikoski, M.; Ulrich, M. H.; Waltman, E.B.; Wamsteker, W.; Wright, M.C.H. (1999)
      We present a wide multi-wavelength database of most observations of the quasar 3C273 obtained during the last 30 years. This database is the most complete set of observations available for an active galactic nucleus (AGN). ...

    • 3C 279 Multiwavelength Monitoring II : The Ground-based Campaign 

      Grandi, P.; Urry, C.M.; Maraschi, L.; Wehrle, A. E.; Madejski, G. M.; Aller, M. F.; Aller, H. D.; Bailyn, C. D.; Balonek, T.J.; Bock, T. H.; Glass, I. S.; Litchfield, S.J.; McHardy, I.M.; Mulchaey, J. S.; Reuter, H.-P.; Robson, E. I.; Sadun, A. C.; Sherry, W.; Steppe, H.; Stevens, Jason; Teraesranta, H.; Tornikoski, M.; Wagner, S.J. (1996-03-01)
      The optically violently variable quasar 3C 279 was monitored simultaneously from radio to y-ray frequencies in 1992 December-1993 January. We report a detailed study of the ground-based results from radio to optical ...

    • LeMMINGs – I. The eMERLIN legacy survey of nearby galaxies. 1.5-GHz parsec-scale radio structures and cores 

      Baldi, R. D.; Williams, D.R.A.; McHardy, I.M.; Beswick, R.J.; Argo, M. K.; Dullo, B. T.; Knapen, J. H.; Brinks, Elias; Muxlow, T. W. B.; Aalto, S.; Alberdi, A.; Bendo, G. J.; Corbel, S.; Evans, R.; Fenech, D.M.; Green, D. A.; Klöckner, H. R; Körding, E.; Kharb, P.; Maccarone, T. J.; Martí-Vidal, I.; Mundell, C. G.; Panessa, F.; Peck, A. B.; Pérez-Torres, M. A.; Saikia, D. J.; Shankar, F.; Spencer, R. E.; Stevens, I. R.; Uttley, P.; Westcott, J. (2018-05-21)
      We present the first data release of high-resolution (≤0.2 arcsec) 1.5-GHz radio images of 103 nearby galaxies from the Palomar sample, observed with the eMERLIN array, as part of the LeMMINGs survey. This sample includes ...

    • Multiwavelength Observations of a Dramatic High-Energy Flare in the Blazar 3C 279 

      Wehrle, A. E.; Pian, E.; Urry, C.M.; Maraschi, L.; McHardy, I.M.; Lawson, A.J.; Ghisellini, G.; Hartman, R.C.; Madejski, G.M.; Makino, F.; Marscher, A.P.; Wagner, S.J.; Webb, J.R.; Aldering, G.S.; Aller, M.F.; Aller, H.D.; Backman, D.E.; Balonek, T.J.; Boltwood, P.; Bonnell, J.; Caplinger, J.; Celotti, A.; Collmar, W.; Dalton, J.; Drucker, A.; Falomo, R.; Fichtel, C.E.; Freudling, W.; Gear, W.K.; Gonzalez-Perez, N.; Hall, P.; Inoue, H.; Johnson, W.N.; Kazanas, D.; Kidger, M.R.; Kii, T.; Kollgaard, R.I.; Kondo, Y.; Kurfess, J.; Lin, Y.C.; McCollum, B.; McNaron-Brown, K.; Nagase, F.; Nair, A.D.; Penton, S.; Pesce, J.E.; Pohl, M.; Raiteri, C.M.; Renda, M.; Robson, E.I.; Sambruna, R.M.; Schirmer, A.F.; Shrader, C.; Sikora, M.; Sillanpaeae, A.; Smith, P.S.; Stevens, Jason; Stocke, J.; Takalo, L.O.; Teraesranta, H.; Thompson, D.J.; Thompson, R.; Tornikoski, M.; Tosti, G.; Treves, A.; Turcotte, P.; Unwin, S.C.; Valtaoja, E.; Villata, M.; Xu, W.; Yamashita, A.; Zook, A. (1998-04-01)
      The blazar 3C 279, one of the brightest identified extragalactic objects in the γ-ray sky, underwent a large (factor of ~10 in amplitude) flare in γ-rays toward the end of a 3 week pointing by Compton Gamma Ray Observatory ...

    • Multiwavelength Observations of Markarian 421 During a TeV/X-Ray Flare 

      Macomb, D.J.; Akerlof, C.; Aller, H. D.; Aller, M. F.; Bertsch, D. L.; Bruhweiler, F.; Buckley, J.H.; Carter-Lewis, D.A.; Cawley, M.F.; Cheng, K.-P.; Dermer, C.; Fegan, D.J.; Gaidos, J.A.; Gear, W.K.; Hall, C.R.; Hartman, R.C.; Hillas, A.M.; Kafatos, M.; Kerrick, A.D.; Kniffen, D.A.; Kondo, Y.; Kubo, H.; Lamb, R.C.; Makino, F.; Makishima, K.; Marscher, A.; McEnery, J.; McHardy, I.M.; Meyer, D.I.; Moore, E.M.; Ramos, E.; Robson, E.I.; Rose, H.J.; Schubnell, M.S.; Sembroski, G.; Stevens, Jason; Takahashi, T.; Tashiro, M.; Weekes, T.C.; Wilson, C.; Zweerink, J. (1995-08-01)
      A TeV flare from the BL Lac object Mrk 421 was detected in May of 1994 by the Whipple Observatory air Cherenkov experiment during which the flux above 250 GeV increased by nearly an order of magnitude over a 2-day period. ...

    • Multiwavelength observations of the February 1996 high-energy flare in the blazar 3C 279 

      Wehrle, A. E.; Pian, E.; Urry, C.M.; Maraschi, L.; Ghisellini, G.; Hartman, R.C.; Madejski, G. M.; Makino, F.; Marscher, A.P.; McHardy, I.M.; Webb, J. R.; Aldering, G. S.; Aller, M. F.; Aller, H. D.; Backman, D.E.; Balonek, T.J.; Boltwood, P.; Bonnell, J.; Caplinger, J.; Celotti, A.; Collmar, W.; Dalton, J.; Drucker, A.; Falomo, R.; Fichtel, C.E.; Freudling, W.; Gear, W.K.; Gonzalez-Perez, N.; Hall, P.; Inoue, H.; Johnson, W. N.; Kidger, M. R.; Kollgaard, R. I.; Kondo, Y.; Kurfess, J.; Lawson, A.J.; McCollum, B.; McNaron-Brown, K.; Nair, D.; Penton, S.; Pesce, J. E.; Pohl, M.; Raiteri, C.M.; Renda, M.; Robson, E.I.; Sambruna, R.M.; Schirmer, A. F.; Shrader, C.; Sikora, M.; Sillanpää, A.; Smith, P.S.; Stevens, Jason; Stocke, J.; Takalo, L.O.; Teräsranta, H.; Thompson, D.J.; Thompson, R.; Tornikoski, M.; Tosti, G.; Turcotte, P.; Treves, A.; Unwin, S.C.; Valtaoja, E.; Villata, M.; Wagner, S.J.; Xu, W.; Zook, A. C. (American Institute of Physics (AIP), 1997-05-01)
      We report CGRO, RXTE, ASCA, ROSAT, IUE, HST and ground-based observations of a large flare in 3C 279 in February 1996. X-rays and γ-rays peaked simultaneously (within one day). We show simultaneous spectral energy distributions ...

    • Submillimetre photometry of X-ray absorbed quasi-stellar objects: their formation and evolutionary status 

      Stevens, J. A.; Page, M.J.; Ivison, R.J.; Carrera, F.J.; Mittaz, J.P.D.; Smail, I.; McHardy, I.M. (2005-06)