150 yars later... I am taking spectra of several Be stars with an echelle spectrograph and a C11 telescope. This is part of the ARAS and BeSS Be Star Spectra monitoring program.
What is interesting is that sometimes a star which didn't show emission recently suddently display an emission in its spectrum. This is the case of V442 And which I just took. The first look into the spectrum clearly show a narrow emission superimposed over the Halpha absorption line of the star. This is coming from a disk of material surrounding the star (material coming from the star itself through a mechanism not completely understood, some Non Radial Pulsation seem the main cause but maybe not the sole one).
As I reduced the first spectrum of the serie I am taking, I noticed the narrow emission:
The emission was not visible on a spectrum taken 20 days ago:
YOUPI - I just discovered an outburst of a Be star. Not a very frequent event!
Here is the screenshot of the observatory PC duyring acquisition:
After proper data reduction, here is a comparison with Valérie Desnoux spectrum dated 31-july, the emission seems to be visible on Valérie's spectrum but just starting:
A look at previous years show that V442 And is a very active Be star with period of quiet and period of outbursts. The required observation period in ARASBeAm is set at 30 days so a continuous observation of this target seems a good idea. There are 97 spectra of this star in ARASBeAm/BeSS database. Here is a graph with a spectrum taken about every year:
UPDATE from August 24th:
In less than 48 hours, the emission changed drastically and now it is a clear double peak with the R (Red) peak higher than the V (Violet) one:
UPDATE from August 25th:
In 24hours, the V/R inverted and now the V peak is higher than the R one!
But a 4h monitoring on the same star didn't show any obvious changes in the profile during the night:
Be stars rocks! :-)
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