April 25, 2018: Dr. Jeno Sokoloski (Columbia University) and Mx. Adrian Lucy (graduate student, Columbia University) have requested AAVSO observations in support of a search underway by Mx. Lucy for symbiotic stars.
Dr. Sokoloski writes: "My graduate student (Adrian Lucy) is searching for new symbiotic stars and has identified a few candidates. What we need is some fast photometry (any filter, but V or B would probably be best) to check for CV-like flickering. If we find flickering, it would confirm that these giants are actually newly discovered symbiotic stars!
"Ideally, we would want light curves that are at least a few hours long, with cadences of no longer than, say, 20 minutes (with even shorter cadence being even better, if the error bars do not become too large)...[The cadence depends] on the size of the telescope being used. Basically, we need the error bars to be small enough to detect flickering with an amplitude of about 10% or a few tens of percent."
The list of targets is as follows:
| Name | RA (2000) | Dec (2000) | Vmag |
Visibility |
|---|---|---|---|---|
| ASASSN-V J081823.00-111138.9 | 08 18 23.00 | -11 11 38.9 | 12.5 | near end of observing season |
| CD-28 10578 | 14 18 28.91 | -28 39 03.7 | 11.7 | obs season recently started |
| NSVS J1444107-074451 | 14 44 10.68 | -07 44 49.4 | 13.1 | obs season recently started |
| GSC 09276-00130 | 17 18 09.29 | -67 57 26.0 | 13.6 | at start of obs season |
| ASAS J195948-8252.7 | 19 59 48.42 | -82 52 37.5 | 11.6 | far-southern circumpolar |
Fast photometry (V or B preferred) as described above is requested.
The AAVSO observations will not only help determine if these targets are symbiotics, but will also help refine the candidate selection procedure by showing whether fast flickering or spectroscopy provides a better clue.
More candidates will be announced from time to time as Mx. Lucy's research proceeds; observers will be informed via AAVSO Alert Notices and posts to the AAVSO forum thread given below. Observers will also be informed via posts to this thread when candidates need no longer be observed.
Charts with comparison star sequences for these stars may be created using the AAVSO Variable Star Plotter (VSP). Be sure to include spaces in names as shown below:
ASASSN-V J081823.00-111138.9
CD-28 10578
NSVS J1444107-074451
GSC 09276-00130
ASAS J195948-8252.7
Please submit observations to the AAVSO International Database using the names given in the table above. Again, be sure to include spaces in names as shown above.
This campaign is being followed on the AAVSO Campaigns and Observing Reports online forum at
https://www.aavso.org/symbiotic-candidates-campaign
This AAVSO Alert Notice was compiled by Elizabeth O. Waagen.
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