The following document lists the file abstract/BARR_AGN_M501TOO.abs
from catalogue VI/111.
A plain copy of the file
(without headers/trailers) may be downloaded.
We propose an ISO target of Opportunity observation of the BL Lacartae object Markarian 501 which is currently undergoing a major outburst at TeV energies. According to many current theories of the emission processes in blazras, the far-IR continuum provides the seed photons for inverse Compton gamma rays, so a gamma-ray outburst should be accompanied (and preceeded) by a far-IR outburst. Unfortunately, since the launch of ISO, only one blazar outburst (3C279) has been observed by ISO, and that in PV phase where the quality of the ISO data are less than optimum. Furthermore no Ultra High Energy (UHE) gamma ray measurements were available. This may represent the only chance with ISO to investigate any IR/UHE gamma ray linj in flaring blazars. An accurate measurement of the IR continuum during the current outburst will yield major diagnostics of the physical processes in the emission region of these enigmatic objects.