Upper Limits on TeV Gamma-Ray Emission from Active Galactic Nuclei

The results of a search for TeV gamma-ray emission from 35 active galactic nuclei (AGNs) using the Whipple Observatory High Resolution Atmospheric Cerenkov Camera are reported. Fifteen of these objects have been detected at GeV energies by the EGRET experiment on the {ital Compton} {ital Gamma} {ital Ray} {ital Observatory}. None of the 35 objects gave a signal at the 3 {sigma} level; Mrk 421 remains the only AGN detected at TeV energies. The absence of a TeV signal may imply a change in the primary source spectrum and/or the effect of absorption by pair production on intergalactic infrared photons. {copyright} {ital 1995 The American Astronomical Society.}