spectra of Be stars in the TESS field

[robin_astro]

Meanwhile with the LHIRES spectrograph, for the past month I have been following a number of Be stars in the field of the TESS satellite at H alpha and He6678A at a resolving power of R=5500 contributing to a Pro Am study trying to correlate star activity with disc formation.  Although there have not been too many clear nights they only take 30min-1 hour each so it is possible to knock off half a dozen in an evening. The graphic shows the results for selection of different Be stars at H alpha.  The one in red currently has no circumstellar disc so just shows the normal absorption line of a B star. Where a disc is present the emission from the disc is superimposed on the absorption and if the disc is strong enough this completely dominates.  Whether the emission is single or double peaked depends on the orientation of the rotating disc relative to us.  When viewed pole on there is no Doppler broadening from the rotation so we just see a single narrow line. When viewed side on we see two peaks from the two sides of the disc rotating towards and away from us.

Robin

Edited September 25, 2019 by robin_astro

[andrew s]

Nice work Robin.

Regards Andrew

[JeremyS]

Interesting project Robin. Thanks for sharing!