Now showing items 1-20 of 130

• #### A Search for Pulsed TeV Gamma Ray Emission from the Crab Pulsar ﻿

(1999)
We present the results of a search for pulsed TeV emission from the Crab pulsar using the Whipple Observatory's 10m gamma-ray telescope. The direction of the Crab pulsar was observed for a total of 73.4 hours between 1994 ...
• #### Search for Pulsed TeV Gamma-ray Emission from the Crab Pulsar ﻿

(1999)
We present the results of a search for pulsed TeV emission from the Crab pulsar using the Whipple Observatory's 10 m gamma-ray telescope. The direction of the Crab pulsar was observed for a total of 73.4 hours between 1994 ...
• #### A Search for Pulsed TeV Gamma Ray Emission from the Crab Pulsar ﻿

(1999)
We present the results of a search for pulsed TeV emission from the Crab pulsar using the Whipple Observatory's 10m gamma-ray telescope. The direction of the Crab pulsar was observed for a total of 73.4 hours between 1994 ...
• #### Search for Pulsed TeV Gamma-ray Emission from the Crab Pulsar ﻿

(1999)
We present the results of a search for pulsed TeV emission from the Crab pulsar using the Whipple Observatory's 10 m gamma-ray telescope. The direction of the Crab pulsar was observed for a total of 73.4 hours between 1994 ...
• #### Cutoff in the TeV Energy Spectrum of Markarian 421 During Strong Flares in 2001 ﻿

(2001)
Exceptionally strong and long lasting flaring activity of the blazar Markarian 421 (Mrk 421) occurred between January and March 2001. Based on the excellent signal-to-noise ratio of the data we derive the energy spectrum ...
• #### Discovery of Spectral Variability of Markarian 421 at TeV Energies ﻿

(2002)
The detection of spectral variability of the gamma-ray blazar Mrk 421 at TeV energies is reported. Observations with the Whipple Observatory 10m gamma-ray telescope taken in 2000/2001 revealed exceptionally strong and ...
• #### Recent Results from the VERITAS Collaboration ﻿

(2002)
A decade after the discovery of TeV gamma-rays from the blazar Mrk 421 (Punch et al. 1992), the list of TeV blazars has increased to five BL Lac objects: Mrk 421 (Punch et al. 1992; Petry et al. 1996; Piron et al. 2001), ...
• #### A Very High Energy Gamma-Ray Spectrum of 1ES 2344+514 ﻿

(2005)
The BL Lacertae (BL Lac) object 1ES 2344+514 (1ES 2344), at a redshift of 0.044, was discovered as a source of very high energy (VHE) gamma rays by the Whipple Collaboration in 1995 \citep{2344Catanese98}. This detection ...
• #### TeV Gamma-Ray Observations of the Perseus and Abell 2029 Galaxy Clusters ﻿

(2006)
Galaxy clusters might be sources of TeV gamma rays emitted by high-energy protons and electrons accelerated by large scale structure formation shocks, galactic winds, or active galactic nuclei. Furthermore, gamma rays may ...
• #### Observations of the Unidentified TeV Gamma-Ray Source TeV J2032+4130 with the Whipple Observatory 10 m Telescope ﻿

(2006)
We report on observations of the sky region around the unidentified TeV gamma-ray source TeV J2032+4130 carried out with the Whipple Observatory 10 m atmospheric Cherenkov telescope for a total of 65.5 hrs between 2003 and ...
• #### The First VERITAS Telescope ﻿

(2006)
The first atmospheric Cherenkov telescope of VERITAS (the Very Energetic Radiation Imaging Telescope Array System) has been in operation since February 2005. We present here a technical description of the instrument and a ...
• #### Multiwavelength Observations of 1ES 1959+650, One Year After the Strong Outburst of 2002 ﻿

(2006)
In April-May 2003, the blazar 1ES 1959+650 showed an increased level of X-ray activity. This prompted a multiwavelength observation campaign with the Whipple 10 m gamma-ray telescope, the Rossi X-ray Timing Explorer, the ...
• #### Multiwavelength Observations of Markarian 421 in March 2001: an Unprecedented View on the X-ray/TeV Correlated Variability ﻿

(2007)
(Abridged) We present a detailed analysis of week-long simultaneous observations of the blazar Mrk421 at 2-60 keV X-rays (RXTE) and TeV gamma-rays (Whipple and HEGRA) in 2001. The unprecedented quality of this dataset ...
• #### Very High Energy Observations of Gamma-Ray Burst Locations with the Whipple Telescope ﻿

(2007)
Gamma-ray burst (GRB) observations at very high energies (VHE, E &gt; 100 GeV) can impose tight constraints on some GRB emission models. Many GRB afterglow models predict a VHE component similar to that seen in blazars and ...
• #### Kinematics of the Broad Line Region in M81 ﻿

(2007)
A new model is presented which explains the origin of the broad emission lines observed in the LINER/Seyfert nucleus of M81 in terms of a steady state spherically symmetric inflow, amounting to 1 x 10^-5 Msun/yr, which is ...
• #### Deep optical observations of the interaction of the SS 433 microquasar jet with the W 50 radio continuum shell ﻿

(2007)
Four mosaics of deep, continuum-subtracted, CCD images have been obtained over the extensive galactic radio continuum shell, W 50, which surrounds the remarkable stellar system SS 433. Two of these mosaics in the Halpha+[N ...
• #### VLT / Infrared Integral Field Spectrometer Observations of Molecular Hydrogen Lines in the Knots in the Planetary Nebula NGC 7293 (the Helix Nebula) ﻿

(2007)
Knots are commonly found in nearby planetary nebulae (PNe) and star forming regions. Within PNe, knots are often found to be associated with the brightest parts of the nebulae and understanding the physics involved in knots ...
• #### CO abundances in a protostellar cloud: freeze-out and desorption in the envelope and outflow of L483 ﻿

(2007)
CO isotopes are able to probe the different components in protostellar clouds. These components, core, envelope and outflow have distinct physical conditions and sometimes more than one component contributes to the observed ...
• #### Rotational Modulation of M/L Dwarfs due to Magnetic Spots ﻿

(2007)
We find periodic I-band variability in two ultracool dwarfs, TVLM 513-46546 and 2MASS J00361617+1821104, on either side of the M/L dwarf boundary. Both of these targets are short-period radio transients, with the detected ...
• #### A search for CO+ in planetary nebulae ﻿

(2007)
We have carried out a systematic search for the molecular ion CO+ in a sample of 8 protoplanetary and planetary nebulae in order to determine the origin of the unexpectedly strong HCO+ emission previously detected in these ...