Thu, 06/18/2020 - 02:19
AAVSO Alert Notice 708 announces a short campaign on 17 symbiotic binary candidates. This campaign is a little different in that only one observation in each filter for each target is needed in order to obtain current magnitudes. Please be sure to read the notice for details and observing instructions.
Many thanks, and Good observing,
Elizabeth O. Waagen, AAVSO HQ
Below is the table which shows the status of coverage of the targets in AAVSO Alert Notice 708. When a filter field is marked "done", please do not observe that target in that field any more. Please watch this table to see what is still needed. Also, please check the AAVSO Light Curve Generator (LCG) to see if data for a target have been received since the table was updated. (Use JD 2459018 as the starting date for plotting using the LCG.)
If you have questions, please post in this thread.
Many thanks, and good observing - Elizabeth
Latest update: 2 July 2020
THIS CAMPAIGN IS NOW CLOSED (July 2, 2020). THANKS TO ALL WHO CONTRIBUTED!
NO ADDITIONAL V OR B OBSERVATIONS ARE NEEDED.
U OBSERVATIONS ARE STILL USEFUL IF YOU HAVE THE TIME AND RESOURCES. PLEASE POST IN THIS FORUM THREAD IF YOU SUBMIT U OBSERVATIONS.
Note: Coordinates are from the VSX pages for these stars
I'm having trouble with this first item called ASAS J150924-5303.5
I can't find any reference to it in the ASAS database or in Simbad.
I have taken a test exposure and there isn't a star on my image at the coordinates. This may be because it is too dim of course. I have attached a screenshot from VPhot,
I searched on VSX and found an entry, then selected ASAS Light Curve from External Links that led me to this:
The Simbad external link gave nothing though, as you say.
Hi Terry— As David says, it shows up in a VSX search, typing ASAS J150924-5303.5 in the name field. It's a Mira, so it may indeed have dimmed too much for your exposure's depth. Typing in the coordinates in Aladin-Lite (https://aladin.u-strasbg.fr/AladinLite/) and rotating your image 180 deg to match, I think your labelled location looks close to correct. If you can get a rough upper limit (you can just post in the forum if uploading upper limits is too complicated), that could be useful.
The ASASSN-V light curve on Sky Patrol (https://asas-sn.osu.edu) suggests a magnitude range ~13.5--16.7.
I have taken a few images for these stars on 19/6/2020
ASAS J152058-4519.7 V=12.87 B=14.25
NSV 20400 V= 13.56 B=14.51
Gaia DR2 6043925532812301184 V=15.21 B=16.41
I also tooka spectra of NSV20400.
It shows nice emission lines.
ASAS J150924-5303.5 is in Simbad as IRAS 15057-5252. I did a coordinate search in Simbad and found the IRAS name in VSX as an alternate ID.
Thanks for participating in this campaign!
I have imaged 3 of these (2MASS J185....GSC 05140...... and IRAS F19019......) in B and V from SRO; reduced the data and uploaded to the AID. I plan to do about 7 more of them that are in the North.
Thank you all very much for completing this project so quickly—your results have been essential for choosing exposure times for our light curves now entered into the observing queue of the Las Cumbres Observatory network. In 2 weeks, you completed B and V band results for all targets. (We're closing the campaign, but for anyone with the time and resources, U band observations remain useful. If possible, please comment in the forum if you get U band magnitudes for new targets, as I'll no longer be checking the light curve generator results for each target very regularly.)
Thank you again! --Adrian