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Updated: Jul 12, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Summary
Pulsar intensity fluctuations suggest interstellar medium irregularities. These scintillations indicate pulsar angular sizes are less than 0.3 micro-arcseconds, impacting radio source angular diameter.
Area of Science:
- Astronomy and Astrophysics
- Radio Astronomy
Background:
- Pulsars are rapidly rotating neutron stars emitting beams of electromagnetic radiation.
- Interstellar medium (ISM) can affect radio wave propagation, causing observed intensity variations.
Purpose of the Study:
- To investigate time fluctuations in pulsed radio signals from specific pulsars.
- To determine if observed fluctuations align with interstellar scintillation theory.
Main Methods:
- Analysis of power spectra, modulation indices, frequency distributions, and decorrelation frequencies.
- Modeling interstellar scintillation effects.
Main Results:
- Fluctuations in pulsar intensity are consistent with interstellar scintillation.
- Estimated scale size of ISM irregularities: ~10^4 km.
- Estimated distance to irregularities: ~70 parsecs.
- Estimated pulsar angular diameter: < 0.3 x 10^-5 arcseconds.
Conclusions:
- Interstellar medium irregularities cause observed pulsar intensity variations.
- The study provides constraints on pulsar angular sizes and the apparent angular broadening of point radio sources.
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