THE OPTICAL JET OF 3C273 - AN ELECTRON POSITRON PLASMA BEAM VIEWED BY THE LIGHT OF ITS QUASAR

The nearby bright quasar 3C273 has an extended multiband jet whose spatial pattern of intensity differs strongly from band to band. We propose that only the radio power of the jet is accounted for by the usual synchrotron model. All the higher energy photons seen are instead secondary, 'misdirected' photons from the bright quasar core scattered our way by material within the jet. This model gives a good account of form, spectrum, polarization and intensity pattern along the jet in all the higher bands. Dust cannot plausibly scatter the X-rays seen, but Thomson scattering fits all bands well. Ordinary hydrogen plasma demands uncomfortably high scattering mass. A thousand-fold reduction in mass is secured if the scattering material, though not the main flow, is an electron-positron plasma.