Upper Limits on the Continuum Emission from Geminga at 74 and 326 MHz

Abstract

We report a search for radio continuum emission from the gamma-ray pulsar Geminga. We have used the VLA to image the location of the optical counterpart of Geminga at 74 and 326 MHz. We detect no radio counterpart. We derive upper limits to the pulse-averaged flux density of Geminga, taking diffractive scintillation into account. We find that diffractive scintillation is probably quenched at 74 MHz and does not influence our upper limit, S<56 mJy (2 sigma), but that a 95% confidence level at 326 MHz is S<5 mJy. Owing to uncertainties on the other low-frequency detections and the possibility of intrinsic variability or extrinsic variability (refractive interstellar scintillation) or both, our nondetections are nominally consistent with these previous detections.

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Document Details

Document Type
Technical Report
Publication Date
Dec 20, 1999
Accession Number
ADA464434

Entities

People

  • Namir E. Kassim
  • T. Joseph W. Lazio

Organizations

  • United States Naval Research Laboratory

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Astronomy
  • Bandwidth
  • Detection
  • Dynamic Range
  • Emission
  • Flux Density
  • Frequency
  • Gamma Rays
  • Military Research
  • Observation
  • Radio Astronomy
  • Scattering
  • Scintillation
  • Spectra
  • Uncertainty
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics
  • Optical Physics and Photonics.
  • Solar Physics

Technology Areas

  • Space