AAVSO: American Association of Variable Star Observers

Proposal #166

Proposer (19770) Joshua Hamilton (hami.christ@gmail.com) obscode: HJRA
Assigned To(3663) Dirk Terrell
Date SubmittedNov. 28, 2020

I am currently doing further research on WW Vul (https://www.aavso.org/vsx/index.php?view=detail.top&oid=38220). This is a star that has been studied for over a century, and conclusive period(s) have not been able to be established. I am currently comparing AAVSO photometry charting back to the late 1990's with other light curves from ASAS and other studies on WW Vul that gave suggested periods or semi-periods (as a YSO, it is not uncommon to have either no regular period, or difficult to determine periods). In addition to my seeking to develop or confirm a period or quasi-period, I am also researching the possibility of stellar pulsation in this particular YSO.

Some of the research on this star indicates that the star may pulse at a low frequency at a rate of 5d to the negative 1 power (.2 days). I would like to attempt to detect (or not detect) these low frequency pulsations. I am proposing a 1 night observation with frequencies of imaging every 1 or 2 hours (should only need 180 - 300 second exposure each time as WW Vul is a bright star). If possible, these images should be taken in V, B, and I bands each time.

If possible, I'd like to then like to run for another set of images on a subsequent night (within a week or two) to confirm or refute findings of low frequency pulsations.

Target RA (H.HH) Dec (D.DD) Magnitude Telescope Observation Frequency Expiration Date Proprietary Term
WW Vul 19.432986 21.20870 12.94–10.25 BSM_NH2 once May 31, 2021 No


(3663) Dirk Terrell — Nov. 30, 2020, 1:03 p.m.

The TAC views this proposal positively, although with a suspected period of 0.2 days, the cadence would need to be higher. Suggest that a continuous time series on a couple of nights. Since it is only visible now for about an hour after sunset, we suggest some preliminary BVI datasets now to get exposures right, then do the time series when the target is better situated. If this is ok with the proposer, we will move forward with this plan.

(19770) Joshua Hamilton — Nov. 30, 2020, 8:51 p.m.

That sounds like a great plan - thank you!

(4726) Kenneth Menzies — Dec. 2, 2020, 12:48 p.m.

Committed to NM. Runs once in BVI. Will reactivate in Spring when it is again visible long enough for a time series.

Comments on this proposal are closed.