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Full-Text Articles in Astrophysics and Astronomy
The Recent High State Of The Bl Lacertae Object Ao 0235 And Cross-Correlations Between Optical And Radio Bands, M. Roy, I. E. Papadikis, E. Ramos-Colon, R. Sambruna, K. Tsinganos, J. Papamastorkis, Menas Kafatos
The Recent High State Of The Bl Lacertae Object Ao 0235 And Cross-Correlations Between Optical And Radio Bands, M. Roy, I. E. Papadikis, E. Ramos-Colon, R. Sambruna, K. Tsinganos, J. Papamastorkis, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
We present new optical (B, V , R, I) and radio (at 14.5, 8.5, and 4.8 GHz) observations of the γ-ray- loud blazar AO 0235+164 obtained during the high state of 1997 December-1998 January. The data were combined with historical light curves from the literature to study correlated optical and radio variations over a time span of more than 20 years. Flux variability with large and energy-dependent amplitude is observed at both wave bands, with the source varying over all timescales sampled (years-months- days), in agreement with previous reports. We have performed a cross-correlation analysis of optical and radio light …
Multiwavelength Observations Of Markarian 421 During A Tev/X-Ray Flare, D. J. Macomb, C. W. Akerlof, H. D. Aller, M. F. Aller, D. L. Bertsch, Menas Kafatos
Multiwavelength Observations Of Markarian 421 During A Tev/X-Ray Flare, D. J. Macomb, C. W. Akerlof, H. D. Aller, M. F. Aller, D. L. Bertsch, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
A Te V 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. Contemporaneous observations by ASCA showed the X-ray flux to be in a very high state. We present these results, combined with the first ever simultaneous or nearly simultaneous observations at Ge V gamma-ray, UV, IR, mm, and radio energies for this nearest BL Lac object. While the GeV gamma-ray flux increased slightly, there is little evidence for variability …
Osse Observations In Blazars, K. Mcnaron-Brown, W. N. Johnson, G. V. Jung, R. L. Kinzer, J. D. Kurfess, M. S. Strickman, C. D. Dermer, D. A. Grabelsky, W. R. Purcell, M. P. Ulmer, Menas Kafatos, P. A. Becker, R. Staubert, M. Maisack
Osse Observations In Blazars, K. Mcnaron-Brown, W. N. Johnson, G. V. Jung, R. L. Kinzer, J. D. Kurfess, M. S. Strickman, C. D. Dermer, D. A. Grabelsky, W. R. Purcell, M. P. Ulmer, Menas Kafatos, P. A. Becker, R. Staubert, M. Maisack
Mathematics, Physics, and Computer Science Faculty Articles and Research
Results are reported on observations obtained with the Oriented Scintillation Spectrometer Experiment (OSSE) instrument on the Compton Gamma Ray Observatory (CGRO) of 17 active galactic nuclei (AGNs) known to exhibit blazar properties at other wavelengths. These observations span the period from 1991 June through 1994 May. Of the 33 high-confidence EGRET detections of blazars during CGRO observing phases 1 and 2 (1991 May 16-1993 September 7), OSSE has observed eight and detected five, namely 3C 273, 3C 279, PKS 0528+134, CTA 102, and 3C 454.3. Additionally, OSSE has detected the BL Lac sources H1517+65.6 and PKS 2155-304, which were not …