HR Lyrae (Nova Lyr 1919): from outburst to active quiescence

Jeremy Shears; Gary Poyner

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HR Lyrae (Nova Lyr 1919): from outburst to active quiescence

Jeremy Shears·Gary Poyner

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Abstract

Nova Lyrae was discovered at the Harvard College Observatory on 1919 December 6 at magnitude 6.5. We present a lightcurve for this nova based on published and archival observations. This was a classical fast nova, probably of type B. Decline times were t2 = 31 or 47d, depending on the method used, and t3 = 97d. The amplitude was at least 9.5 magnitudes. Based on our t2 values, we estimate that the absolute magnitude at maximum was -6.9 or -7.2 (+ or -1.1) and at minimum is +2.3 or +2.6 (+ or - 1.1). The star shows an active quiescence with brightness variations on a variety of timescales. Visual observations over a period of ten years also reveal long periods when the star was around 15.4v and others when it was close to 15.7v. Finally, we point out that some characteristics of the star are similar to those of recurrent novae and propose further monitoring of future activity.

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Jeremy Shears, Gary Poyner. 2007-01-25. HR Lyrae (Nova Lyr 1919): from outburst to active quiescence. https://arxiv.org/abs/astro-ph/0701719

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