A. C. Rovero

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.}

Very high-energy gamma-ray emission from the Blazar Markarian-421

Very high energy gamma-ray emission from the BL Lac object Markarian 421 has been detected over three observing seasons on 59 nights between April 1992 and June 1994 with the Whipple 10-meter imaging Cherenkov telescope. During its initial detection in 1992, its flux above 500 GeV was 1.6

Upper limits from five years of blazar observations with the VERITAS Cherenkov telescopes

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Absolute calibration of a large-diameter light source

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Redshift measurement of the BL-Lac gamma-ray blazar PKS 1424+240

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Very-high-energy observations of the binaries V 404 Cyg and 4U 0115+634 during giant X-ray outbursts

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Detecting extended gamma-ray emission with the next generation Cherenkov telescopes

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Constraints on cosmic-ray origin from TeV gamma-ray observations of supernova remnants

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Search for radio counterpart of the Fermi/VERITAS PWN candidate in the SNR CTA 1

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Operating Water Cherenkov Detectors in high altitude sites for the Large Aperture GRB Observatory

. Observations in 1993 confirmed this level of emission. For observations made between December 1993 and April 1994, its intensity was a factor of 2.2