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I saw in October’s Journal a report that HR Lyr (Nova Lyr 1919) underwent a deep fade to mag 17 at the end of August (Shears and Poyner, observers notes p317) and a spectrum taken then showed strong emission lines (ATel 9418) so I thought I would take a look with my ALPY 200.
Estimating the brightness from the guider image gave mag 16.5 so it looks like it is on its way back to normal quiescence.
The spectrum shows a blue continuum (similar to a late A, early F type star) but with no obvious features above the noise. At this resolution and SNR (R~120 SNR ~27) a narrow emission line would need to be fairly strong to be detected but the H alpha EW of 22 Angstrom quoted in the ATel would I think have been significantly above the noise. It appears likely therefore that the emission has faded.
The spectrum, with ~ 2 sigma uncertainties and a typical F2v spectrum (Pickles) overlaid is attached below
Robin
Thanks for posting this Robin. It does indeed look like HR Lyr is on it’s way up to it’s normal quiescence – which can be quite active by the way.
So the emission lines fade whilst HR Lyr recovers. What do you make of that?
Gary
Hi Gary,
ATel 9418 makes the suggestion that the H alpha emission at least may be present at times weakly even in the normal quiescent state and stays at the same absolute strength but becomes more obvious as the continuum drops (ie constant flux but increasing Equivalent Width relative to the continuum) My spectrum is not really good enough to confirm this though.
I did also have a try with the ALPY at normal resolution (Thanks to the support from the Harold Rildley grant I now have the capability to switch resolution more easily) but the SNR at this magnitude is too poor to show any more than the general continuum shape. I wonder if the Asiago team are still keeping an eye on it with the 1.2m telescope?
Robin
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