Pulsed optical emission from Geminga

A. Shearer; A. Golden; S. Harfst; R. Butler; R. M. Redfern; C. M. O'Sullivan; G. M. Beskin; S. I. Neizvestny; V. V. Neustroev; V. L. Plokhotnichenko; M. Cullum; A. Danks

arXiv · astro-ph/9802225

Pulsed optical emission from Geminga

A. Shearer·A. Golden·S. Harfst·R. Butler·R. M. Redfern·C. M. O'Sullivan·G. M. Beskin·S. I. Neizvestny·V. V. Neustroev·V. L. Plokhotnichenko·M. Cullum·A. Danks

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Abstract

We present optical data which shows that G", the optical counterpart of the gamma-ray pulsar Geminga, pulses in B with a period of 0.237 seconds. The similarity between the optical pulse shape and the gamma-ray light curve indicates that a large fraction of the optical emission is non-thermal in origin - contrary to recent suggestions based upon the total optical flux. The derived magnitude of the pulsed emission is m_B = 26.0 +/- 0.4. Whilst it is not possible to give an accurate figure for the pulsed fraction (due to variations in the sky background) we can give an upper limit of m_B ~ 27 for the unpulsed fraction.

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A. Shearer, A. Golden, S. Harfst, R. Butler, R. M. Redfern, C. M. O'Sullivan, G. M. Beskin, S. I. Neizvestny, V. V. Neustroev, V. L. Plokhotnichenko, M. Cullum, A. Danks. 1998-02-17. Pulsed optical emission from Geminga. https://arxiv.org/abs/astro-ph/9802225

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