Statistics of the MASIV 5 GHZ VLA Scintillation Survey

Abstract

We are undertaking a large-scale VLA 5 GHz variability survey of the northern sky searching for rapid intra-day variability. From four epochs of observations spread over a year we find 56% of the flat-spectrum sources showed significant variability on time-scales from hours to days, with many sources varying episodically on only one epoch during the year. We find that the weaker sources show more frequent variability as well as fractionally larger amplitude variability. Fewer sources were detected at high Galactic latitude, demonstrating that inter-stellar scintillation is the principal mechanism responsible for this IDV. We also see a significant dependence on spectral index with the flatter and more inverted sources more frequently exhibiting scintillation.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 2007
Accession Number
ADA483314

Entities

People

  • Barney Rickett
  • Cliff Senkbeil
  • David Jauncey
  • Hayley Bignall
  • James Lovell
  • Jean-Pierre Macquart
  • Lucyna Kedziora-chudczer
  • Roopesh Ojha
  • Stanislav Shabala
  • Tapio Pursimo

Organizations

  • United States Naval Observatory

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Australia
  • Classification
  • Electronic Mail
  • Fresnel Zones
  • High Latitudes
  • Latitude
  • Mathematics
  • Observation
  • Observatories
  • Radio Telescopes
  • Scintillation
  • Scintillation Counters
  • Spectra
  • Statistics
  • Surveys
  • Telescopes
  • Universities

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics
  • Mathematics or Statistics