Now showing items 66-85 of 113

  • Radio Imaging of the Very-High-Energy Gamma-Ray Emission Region in the Central Engine of a Radio Galaxy 

    Lang, Mark (2009)
    The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10^12 electron ...
  • A recent change in the optical and gamma ray polarization of the Crab nebula and pulsar 

    Moran, Paul; Kyne, Gillian; Redfern, R. M.; Shearer, Andrew (Oxford journals, 2015-12-31)
    We report on observations of the polarization of optical and γ-ray photons from the Crab nebula and pulsar system using the Galway Astronomical Stokes Polarimeter (GASP), the Hubble Space Telescope, Advanced Camera for ...
  • Recent Results from the VERITAS Collaboration 

    Lang, Mark; Gillanders, Gary (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), ...
  • Refinement and validation of an exposure model for the pharmaceutical industry 

    Mc Donnell, Patricia E.; Coggins, Marie (2011)
    Objectives: Assessment of worker's exposure is becoming increasingly critical in the pharmaceutical industry as drugs of higher potency are being manufactured. The batch nature of operations often makes it difficult to ...
  • Rotational Modulation of M/L Dwarfs due to Magnetic Spots 

    Butler, Ray (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 brief optical flashes associated with the SETI target KIC 8462852 

    Gillanders, Gary; Lang, Mark (IOP Publishing, 2016-02-18)
    The F-type star KIC. 8462852 has recently been identified as an exceptional target for search for extraterrestrial intelligence (SETI) observations. We describe an analysis methodology for optical SETI, which we have used ...
  • A search for CO+ in planetary nebulae 

    Redman, Matt P. (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 ...
  • A Search for Dark Matter Annihilation with the Whipple 10m Telescope 

    Lang, Mark (2008)
    We present observations of the dwarf galaxies Draco and Ursa Minor, the local group galaxies M32 and M33, and the globular cluster M15 conducted with the Whipple 10m gamma-ray telescope to search for the gamma-ray signature ...
  • A search for optical bursts from RRAT J1819-1458: II. Simultaneous ULTRACAM-Lovell Telescope observations 

    Shearer, Andrew (2011)
    The Rotating RAdio Transient (RRAT) J1819-1458 exhibits ~3 ms bursts in the radio every ~3 min, implying that it is visible for only ~1 per day. Assuming that the optical light behaves in a similar manner, long exposures ...
  • A search for pulsations from Geminga above 100 GeV with VERITAS 

    Connolly, M.P.; Gillanders, Gary; Moriarty, P.; Lang, Mark (American Astronomical Society, 2015-02-10)
    We present the results of 71.6 hr of observations of the Geminga pulsar (PSR J0633+1746) with the VERITAS very-high-energy gamma-ray telescope array. Data taken with VERITAS between 2007 November and 2013 February were ...
  • A Search for Pulsed TeV Gamma Ray Emission from the Crab Pulsar 

    Lang, Mark; Gillanders, Gary (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 ...
  • A Search for Pulsed TeV Gamma Ray Emission from the Crab Pulsar 

    Lang, Mark; Gillanders, Gary; Burdett, A. M.; Bond, I. H.; Boyle, P. J.; Bradbury, S. M.; Buckley, J. H.; Carter-Lewis, D. A.; Catanese, M.; Cawley, M. F.; D'Vali, M.; Fegan, D. J.; Fegan, S. J.; Finley, J. P.; Gaidos, J. A.; Gillanders, G. H.; Hall, T. A.; Hillas, A. M.; Kildea, J.; Knapp, J.; Krennrich, F.; Lang, M. J.; LeBohec, S.; Lessard, R. W.; Masterson, C.; Moriarty, P.; Quinn, J.; Rose, H. J.; Samuelson, F. W.; Sembroski, G. H.; Srinivasan, R.; Vassiliev, V. V.; Weekes, T. C. (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 

    Lang, Mark; Gillanders, Gary (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 ...
  • Search for Pulsed TeV Gamma-ray Emission from the Crab Pulsar 

    Lang, Mark; Gillanders, Gary; Lessard, R. W.; Bond, I. H.; Bradbury, S. M.; Buckley, J. H.; Burdett, A. M.; Carter-Lewis, D. A.; Catanese, M.; Cawley, M. F.; D'Vali, M.; Fegan, D. J.; Finley, J. P.; Gaidos, J. A.; Gillanders, G. H.; Hall, T.; Hillas, A. M.; Krennrich, F.; Lang, M. J.; Masterson, C.; Moriarty, P.; Quinn, J.; Rose, H. J.; Samuelson, F. W.; Sembroski, G. H.; Srinivasan, R.; Vassiliev, V. V.; Weekes, T. C. (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 ...
  • Simultaneous Multiwavelength Observations of Markarian 421 During Outburst 

    Lang, Mark (2009)
    We report on the results of two coordinated multiwavelength campaigns that focused on the blazar Markarian 421 during its 2006 and 2008 outbursts. These campaigns obtained UV and X-ray data using the XMM-Newton satellite, ...
  • Status of the VERITAS Observatory 

    Lang, Mark; Gillanders, Gary (2008)
    VERITAS, an Imaging Atmospheric Cherenkov Telescope (IACT) system for gammma-ray astronomy in the GeV-TeV range, has recently completed its first season of observations with a full array of four telescopes. A number of ...
  • The study of neutron star magnetospheres with LOFT 

    Shearer, Andrew (2015)
    The Large Observatory for X-ray Timing, LOFT, is designed to perform fast X-ray timing and spectroscopy with uniquely large throughput (Feroci et al. 2014). LOFT focuses on two fundamental questions of ESA’s Cosmic Vision ...
  • Supersonic turbulence in the cold massive core JCMT 18354-0649S 

    Redman, Matt P. (2009)
    An example of a cold massive core, JCMT 18354-0649S, a possible high mass analogue to a low mass star forming core is studied. Line and continuum observations from JCMT, Mopra Telescope and Spitzer are presented and modelled ...
  • TeV and Multi-wavelength Observations of Mrk 421 in 2006-2008 

    Lang, Mark; Gillanders, Gary (2011)
    We report on TeV gamma-ray observations of the blazar Mrk 421 (redshift of 0.031) with the VERITAS observatory and the Whipple 10m Cherenkov telescope. The excellent sensitivity of VERITAS allowed us to sample the TeV ...
  • TeV Gamma-Ray Observations of the Perseus and Abell 2029 Galaxy Clusters 

    Lang, Mark; Gillanders, Gary (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 ...