Affiliation
None
Fri, 12/20/2019 - 01:38
Hi Everyone
I studied a number of CVs for a short project as part of my Masters degree. Attached is a poster with a summary of my observation of the 2019 superoutburst of VW Hyi in September/October. The poster is just a quick overview, I am looking for questions or comments - if you want I can probably post the whole report or parts of it.
Summary of key findings
1. In addtion to the 'standard' superhumps slightly longer than the rotational frequency, there are shorter period varitions which have also been previously seen in other systems but have no explanation.
2. Compared to historical data the superhump period may be increasing.
Cheers from Western Australia,
- - -Ian- - -
[edited 21/12/19 to correct some spelling mistakes]
File Upload
Thanks for this, Ian - one of my favourites - along with WX Hyi, Z Cha, AH Eri et al!
Are you able to email me your full report.
srh@xtra.co.nz
Kindest regards
Stephen
Hi Stephen - will do. I also observed an outburst of WX Hyi but got clouded out at the critical week. I'd be interested in your comments on the report - I didn't get a lot of feedback from the supervisor but they still gave me an HD :-) By the way I lived in Wellington for 7 years, 2 daughters and a sis-in-law still live there.
Hi Ian,
I am pretty sure you know that I have observed VW Hyi intensively during the time 2012 to 2014 and in 2018. I think it would be an added value for your research to compare whether the properties you menton in your poster did change with time.
Regards,
Josch
Thank you Josch. This report was part of a short project (12 weeks) for my masters so I had limited time. Now though.... I would like to go back over more historical reports to see if the apparent increase in superhump period is real or just an accident of the limited data I used. Thanks again I really would appreciate some feedback, my Masters is finished but there is no reason why I cannot continue studying southern CVs :-)
Hi Ian,
I cannot give much feedback as I did not analyse the data I have taken. I am the data provider and other people interested in those data are doing the analysis as they have the background to do so. I am "just" the amateur astronomer having the possibility to get the data. I could send to you the AAVSO files or say one global file per year of observation. I could also point to you the publications those data have been used in (at least the older ones) as I know about the 2018 data no paper has yet been poped up.
Josch
Hello again Josch
Just to let you know I was planning to present my short study of VW Hyi at the RASNZ conference in NZ this week - but due to travel restrictions it's been postponed!
Anyway I thought you'd like to know that I went back through your data and found the high-cadence data from 2011 especially useful. In your data set as well as mine from 2019 there appears to be a 35-minute periodic signal in the superhump. I also found one at 15 mins but this was not in your data. This is not a harmonic from the Fourier analysis, but an actual variation in the brightness that can be seen. Also I have collated data from the last 15 years and it appears that the early superhump period is increasing. I am writing this up for the newsletter of Variable Stars South and will send you a copy.
Regards,
- - -Ian- - -
Hi again Josch, I would like to know how you got the high-cadence data early in the super-outburst of VW Hyi in 2011. It seems to be 6-second cadence; this is excellent data & I would really recommend collecting another super-outburst at this same cadence rate. I believe I have observed periodic phenomena at 15 minutes and 35 minutes. If true, this would give us clues as to the shape and the processes going on in the accretion disk. Only data can move this suggestion along :-) what instrument did you use to get the 2011 data? The way my scope is configured we can only get about 3 mins per exposure. I can probably get it to about 20sec per exposure but it will need a new software pipeline that will have to go through the Uni's QA process.