RW Cep unusual dimming

[Robin Leadbeater]

RW Cep is experiencing an unusually deep dimming currently (similar to the Great Dimming in Betelgeuse ?)
https://www.astronomerstelegram.org/?read=15800

Currently mag 7.5 it is bright enough for high resolutions but it is not clear what wavelengths would be specifically interesting so Echelle spectra could be useful.

I have taken some carefully relative flux calibrated R~1000 spectra seen here in the BAA database (I will also add any further spectra there)
https://britastro.org/specdb/data_graph ... &multi=yes
and there are some interesting discussions on Cloudy Nights
https://www.cloudynights.com/topic/8542 ... t-dimming/
AAVSO have also issued an alert
https://www.aavso.org/aavso-alert-notice-804



Cheers
Robin

[Robin Leadbeater]

H alpha is in emission

https://britastro.org/specdb/data_graph ... s_id=13128

There may be more lines in emission. An echelle spectrum could be interesting

There are several high resolution spectra in the ELODIE archive but none of these show H alpha in emission (here compared with my spectra)

rwcep_elodie_archive_THO_2022-12-19_Halpha.png (119.79 KiB) Viewed 11492 times

rwcep_elodie_archive_THO_2022-12-19_lowres.png (126.8 KiB) Viewed 11492 times

Cheers
Robin

[Joan Guarro Flo]

Hi Robin and everyone,

That is the result of one RW Cep observation, unfortunately the bad weather didn't leave me any other oportunity to observe it.

I left this in BAA, but I don't know either if exist someone interested in more observatons..

Merry Christmas and Happy Good Year, Joan.

[Robin Leadbeater]

Thanks Joan !

Yes I am sure there are people who will be interested in this (I am in contact with the authors of the ATel and Christoph Quandt who ran a project on the YHG Rho Cas)

Cheers
Robin

[Robin Leadbeater]

Hi joan,

What do you think of the flux calibration of your spectrum ? Is it ok? What did you use as reference star?
The continuum shape is very different from mine and historic spectra in the EOODIE Archive.
https://britastro.org/specdb/data_graph ... 20+Spectra

Cheers
Robin

[Joan Guarro Flo]

Hi Robin,

As you said, the perfect spectrograph doesn't exist, and I'm afraid that an echelle isn't the best tool
for taking a good calibration flux, in my opinion, using a low resolution spectrograph takes very useful
data for it and more easily.

One can see that almost all studies using echelles, represent their data in a horizontal background.

BTW, it's possible that I'll have a good night today and I'll try to take this star again, and go to essay
V photometry with the Piera telescope. It's a pity that SMM one is damaged until the middle of January.

Cheers, Joan.