Multifrequency Observations of BL Lacertae in 1988
Kawai, N.; Matsuoka, M.; Chambers, K. C.; Matthews, K.; Miley, G. K.; Bregman, J. N.; Aller, H. D.; Aller, M. F.; Leacock, R. J.; Smith, A. G.; Balonek, T. J.; Miller, J. S.; Roche, P. F.; Wills, B. J.; Wills, D.; Clegg, R. E. S.; Ohashi, T.; Hoare, M. G.; Valtaoja, E.; Neugebauer, G.; Goodrich, R.; Webb, J. R.; Moriarty-Schieven, G. H.; Terasranta, H.; Hughes, P. A.; Balbus, S. A.; Clements, S. D.; Hereld, M.; Hughes, V. A.; Thronson, H. A.
Japan, United States, Netherlands
Abstract
Simultaneous multiwavelength observations of BL Lacertae were performed on two occasions separated by 1 month in 1988 June and July, covering the radio, submillimeter, infrared, optical, ultraviolet, and X- ray wave bands. In the wide-band photon spectra, the X-ray flux lies clearly above the extension of radio-ultraviolet continuum as expected. The slope of the X-ray spectra is significantly flatter than that at optical-ultraviolet regimes, and its spectral index 0.7-1.0 corresponds to the slope at submillimeter band. Comparison with earlier observations, in fact, indicates that the X-ray flux is correlated with the submillimeter band, and not with the others, and supports the SSC model.