New analysis of the radio source counts
1Mathematics Department, University of Otago, Dunedin, New Zealand.
Nature
|July 25, 1970
Summary
Radio source counts are primarily explained by luminosity evolution, not density evolution. This finding impacts our understanding of cosmic radio source populations.
Area of Science:
- Cosmic evolution
- Radio astronomy
Background:
- Understanding the evolution of extragalactic radio sources is crucial for cosmology.
- Previous models considered both luminosity and density evolution.
Purpose of the Study:
- To determine the dominant factor influencing radio source counts.
- To differentiate between luminosity and density evolution effects.
Main Methods:
- Analysis of deep radio survey data.
- Modeling of source count distributions.
Main Results:
- Luminosity evolution significantly dominates over density evolution.
- Observed radio source counts are best explained by changes in source luminosity over cosmic time.
Conclusions:
- Luminosity evolution is the primary driver of radio source counts.
- This clarifies the nature of radio source populations across cosmic history.
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