Knox Long

Publications (2)0 Total impact

• Source

  Available from: Arne Rau

  Article: The Impact of the Astro2010 Recommendations on Variable Star Science

  Lucianne M. Walkowicz, Andrew C. Becker, Scott F. Anderson, Joshua S. Bloom, Leonid Georgiev, Josh Grindlay, Knox Long, Anjum Mukadam, Andrej Prsa, Joshua Pepper, Arne Rau, Branimir Sesar, Nicole Silvestri, Nathan Smith, Keivan Stassun, Paula Szkody
  [show abstract] [hide abstract]
  ABSTRACT: The next decade of survey astronomy has the potential to transform our knowledge of variable stars. Stellar variability underpins our knowledge of the cosmological distance ladder, and provides direct tests of stellar formation and evolution theory. Variable stars can also be used to probe the fundamental physics of gravity and degenerate material in ways that are otherwise impossible in the laboratory. The computational and engineering advances of the past decade have made large-scale, time-domain surveys an immediate reality. Some surveys proposed for the next decade promise to gather more data than in the prior cumulative history of astronomy. The actual implementation of these surveys will have broad implications for the types of science that will be enabled. We examine the design considerations for an optimal time-domain photometric survey dedicated to variable star science, including: observing cadence, wavelength coverage, photometric and astrometric accuracy, single-epoch and cumulative depth, overall sky coverage, and data access by the broader astronomical community. The best surveys must combine aspects from each of these considerations to fully realize the potential for the next decade of time-domain science.
  03/2009;
• Source

  Available from: articles.adsabs.harvard.edu

  Article: EUVE Observations of VV PUP

  Paula Szkody, Stephane Vennes, Ed Sion, Knox Long
  [show abstract] [hide abstract]
  ABSTRACT: VV Pup is an AM Her type cataclysmic variable with a 44 MG field, a 100 min orbital period and a viewing geometry such that the primary accreting pole passes behind the limb of the white dwarf for a portion of the orbit. EUVE pointed observations as part of the GO program were conducted from Feb 7 to 9, 1993. At that time, VV Pup was in a high state; it only came out of a low accretion episode in Dec 1992, as witnessed by optical observations and its Nov 1992 non-detection by the EUVE all-sky survey. During the Feb observation, the Deep Survey photometer (Lexan) measured, simultaneously with the spectrometers, 72,000 photons in a 42,000 s portion of the exposure, revealing a bright EUV source. We will present the first EUVE spectrum of a magnetic accretor and discuss the differences between the on/off pole phases of the orbit. This work was partially supported by NASA grant NAGW-3158.
  04/1993; 25:827.