CH Cyg 2018

Show your spectra, your results ...

CH Cyg 2018

Postby Francois Teyssier » Sat Feb 10, 2018 11:40 am

New season and still surprizing ...


H beta:
Very deep central narrow absorption (under the continuum)
and a broad and deep absorption at -350 km/s (max velocity = -500 km/s)
chcyg_20180210_191_Hb.png (16.75 KiB) Viewed 306 times

Helium lines (He I) have vanished
chcyg_20180210_191_NaID.png (14.73 KiB) Viewed 304 times

(comparison with the last spectrum in the database, obtained by Joan)

chcyg_20180210_191_6300.png (17.48 KiB) Viewed 304 times

I recall that several professionnal teams are working on our spectra.
Coverage at the best cadency as possible is requested.

François Teyssier
Francois Teyssier
Posts: 1116
Joined: Fri Sep 23, 2011 1:01 pm
Location: Rouen

Re: CH Cyg 2018

Postby Peter Somogyi » Sun May 27, 2018 8:36 pm


Let me report here an experiment I've made.
Last year I've shot 2 x 10 minute exposures for the CaII region (unsent due to low snr and faint blue), that I've repeated yesterday (6 x 10 min, lately found too easy), R~5200 in both cases (35 micron slit, ATIK 428 EXm).
Now using the last year's experiment as a baseline, the emission velocities of that time look as if they were negated:
last year vs yesterday

To compare velocities of more Balmer in overall (borrowing a recent H-beta from Francois):
compare various Balmer and CaII velocities

I will be curious whether we see this -500 km/sec at H-zeta in the database soon (in 2015 we saw -1500 km/s, last year was mostly silent). At least, the lower Balmer lines are now a matter of suspect consisting of both absorptions + emissions.
For now this was just an experiment, documenting the result.

Peter Somogyi
Posts: 302
Joined: Sun Jul 13, 2014 8:56 am

Return to Spectra, results, information on activity ...

Who is online

Users browsing this forum: No registered users and 4 guests