M. F. Cawley

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We have used data from the TeV γ-ray flare associated with the active galaxy Markarian 421 observed on 15 May 1996 to place bounds on the possible energy-dependence of the speed of light in the context of an effective quantum gravitational energy scale. The possibility of an observable time dispersion in high energy radiation has recently received attention(More)
We present multiwavelength observations of the BL Lacertae object Markarian 501 (Mrk 501) in 1997 between April 8 and April 19. Evidence of correlated variability is seen in very high energy (VHE, E ∼ > 350 GeV) γ-ray observations taken with the Whipple Observatory γ-ray telescope, data from the Oriented Scintillation Spectrometer Experiment (OSSE) of the(More)
We present the results of a search for pulsed TeV emission from the Crab pulsar using the Whipple ObservatoryÏs 10-m gamma-ray telescope. The direction of the Crab pulsar was observed for a total of 73.4 hr between 1994 November and 1997 March. During this period the Whipple 10 m telescope was operated at its lowest energy threshold to date. Spectral(More)
Based on BACODINE network notification the Whipple Observatory gamma-ray telescope has been used to search for the delayed TeV counterpart to BATSE-detected gamma-ray bursts. In the fast slew mode, any point in the sky can be reached within two minutes of the burst notification. The search strategy, necessary because of the uncertainty in burst position and(More)
This self-directed learning module highlights new advances in this topic area. It is part of the chapter on spinal cord injury rehabilitation in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This section explores the medical, psychologic, and social challenges facing an individual with(More)
The Crab Nebula has become established as the standard candle for TeV gamma-ray astronomy using the atmospheric Cherenkov technique. No evidence for variability has been seen. The spectrum of gamma rays from the Crab Nebula has been measured in the energy range 500 GeV to 8 TeV at the Whipple Observatory by the atmospheric Cherenkov imaging technique. Two(More)
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 1.6×10 −11 photons cm −2 s −1. Observations in 1993 confirmed this level(More)
Although atmospheric Cherenkov telescopes have restricted fields of view, their fluence sensitivity warrants a search for gamma-ray burst phenomena. A search for 400 GeV gamma-ray bursts on a 1 s timescale using archival data taken between 1988 and 1992 with the Whipple Collaboration 10 m reflector is presented. No evidence of such bursts is found. Bursts(More)
A next generation atmospheric Cherenkov observatory is described based on the Whipple Observatory γ-ray telescope. A total of nine such imaging telescopes will be deployed in an array that will permit the maximum versatility and give high sensitivity in the 50 GeV-50 TeV band (with maximum sensitivity from 100 GeV to 10 TeV). INTRODUCTION Recent successful(More)
Mkn 421 was observed for about two days with BeppoSAX, prior to and partly overlapping the start of a 1 week continuous exposure with ASCA in April 1998, as part of a worldwide multiwavelength campaign. A pronounced, well defined, flare observed in X-rays was also observed simultaneously at TeV energies by the Whipple Observatory's 10 m gamma-ray telescope.(More)
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