A Deep, High-Resolution Survey at 74 MHz

Abstract

We present a 74 MHz survey of a 165 deg^2 region located near the north Galactic pole. This survey has an unprecedented combination of both resolution and sensitivity. We detect 949 sources in this region, enough to begin exploring the nature of the 74 MHz source population. We present differential source counts, spectral index measurements, and the size distribution as determined from counterparts in the high-resolution FIRST 1.4 GHz survey. We find a trend of steeper spectral indices for the brighter sources. Further, there is a clear correlation between spectral index and median source size, with the flat spectrum sources being much smaller on average. Ultra-steep spectrum objects are identified, and we present high-resolution VLA follow-up observations of these sources which, identified at such a low frequency, are excellent candidates for high-redshift radio galaxies.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 2004
Accession Number
ADA464494

Entities

People

  • A. S. Cohen
  • H. J. Roettgering
  • M. J. Jarvis
  • Namir Kassim
  • T. Joseph W. Lazio

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Absorption
  • Detection
  • Flux Density
  • Frequency
  • High Resolution
  • Jet Propulsion
  • Measurement
  • Military Research
  • Observation
  • Observatories
  • Radio Frequency
  • Remote Sensing
  • Sensitivity
  • Shape
  • Spectra
  • Three Dimensional
  • Very Low Frequency

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics