Abstract
Using experimental data on observed pulsars, we have estimated a lower limit for the birth rate of pulsars in our Galaxy to be B1b = 0.0111 (±0.0050) K pulsars yr−1 where K, the ‘beam factor‘, allows for the possibility that only a fraction of all pulsars is beamed towards the Earth. If we take1 K to be 5, we obtain a mean birth rate of 1 pulsar per 18 yr while we can place a firmer lower bound with 95% confidence of 1 per 50 yr. Two important new features of the present approach are: (1) we do not assume any model for pulsars; (2) we have allowed for selection effects (in a model independent way). Apart from obtaining a more reliable number for the birth rate of pulsars, we conclude that the quantity P/(2Ṗ), where P is the period of the pulsar and Ṗ is its time derivative, is probably a good measure of age in “young” pulsars up to half a million years old, and that selection effects which have been neglected in all earlier calculations are significant. The present calculation reduces the discrepancy between pulsar and supernova birth rates.
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References
Manchester, R. N. & Taylor, J. H. Pulsars (Freeman, San Francisco, 1977).
Davies, J. G., Lyne, A. G. & Seiradakis, J. H. Mon. Not. R. astr. Soc. 179, 635–650 (1977).
Hulse, R. A. & Taylor, J. H. Astrophys. J. 201, L55–59 (1975).
Manchester, R. N. et al. Mon. Not. R. astr. Soc. 185, 409–421 (1978).
Lyne, A. G. IAUSymp. No. 95 (1980).
Ostriker, J. P. & Gunn, J. E. Astrophys. J. 157, 1395–1417 (1969).
Narayan, R. & Vivekanand, M. (in preparation).
Lyne, A. G., Ritchings, R. T. & Smith, F. G. Mon. Not. R. astr. Soc. 171, 579–597 (1975).
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Narayan, R., Vivekanand, M. A lower limit for the birth rate of pulsars. Nature 290, 571–572 (1981). https://doi.org/10.1038/290571a0
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DOI: https://doi.org/10.1038/290571a0
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