Affiliation
American Association of Variable Star Observers (AAVSO)
Fri, 02/26/2016 - 21:36
AAVSO Alert Notice 538 announces an observing campaign on the symbiotic star V694 Mon (MWC 560), which is in outburst. Photometry and spectroscopy are requested. Please see the Alert Notice for details.
Good observing,
Elizabeth Waagen, AAVSO HQ
Hi folks. Thanks very much to those who have been obtaining fast photometry of V694 Mon -- the flickering light curves look spectacular! It is particularly great when more than one observer obtains fast photometry, so that we can be confident that all the little bumps and wiggles in the light curve are real. The large amplitude of the flickering suggests that the high state is related to a high rate of accretion through the accretion disk. If the target starts to fade, it will be especially important to determine whether the flickering disappears.
Clear skies,
Jeno
Just echoing Jeno's thanks here---the light curves are looking great and very useful. FYI, the predicted schedule of March 8 (7:17 to 14:14 UT) and March 9 (2:20 to 9:18 UT) are still the most likely times for the Chandra exposures. Data through the rest of March and April will continue to be useful.
Thanks!
Also, I'm interested in whether that sudden drop in B band at March 7, 9:00 is real. Some more data from a few observers in that filter would be nice. Thanks! -Adrian
Hi Adrian,
I imaged V694 Mon last night, it was fairly 'quiet', the Blue data ranged between 9.9 - 10.1.
Regards, Douglas.
Here is my data from last night.
Many thanks to both of you! Yeah, I don't think that drop was real, the data was withdrawn at some point. All the more reason why multiple observers on the same light curve is useful!
The first Chandra exposure is happening today, not sure when we'll get the data. And Swift's gotten a couple ultraviolet spectra and photometry that we're just starting to look at.
I am still collecting several hours of data on V0694 Mon on clear nights. Here is my data from last night.
Real
Hello Barbara and all
Real nice light curve. I too plan to do several hours per clear night on this object. Here is from 2 nights ago. I plan to follow this into April.
WGR
Hi Gary and Barbara and others,
Thanks for your continued attention to this target! We got some interesting X-ray results, which show that the soft X-rays from either the jet or colliding winds have strengthened quite significantly. The Swift observations are continuing, and Adrian and I are now going to try to obtain some radio observations as well.
Clear skies,
Jeno
Jeno,
Thanks for the update. It is nice to hear what is going on with the data we obtain.
Barbara
Hello Jeno
Yes, ditto. Its good to hear that things are ongoing. How far into April do you want us to go, or does that depend upon what the resuts are?
Gary
Hi All,
Joining the party late here.
I started observing this target when the initial notice went out, but haven't continued to follow up. I got BVRI data on 3/3 and 3/6, which I'm uploading to VPhot now.
If these look good, shall I share them via VPhot, or do you have an ftp/Dropbox collection for images?
Clear skies,
Brad Vietje, VBPA
Newbury, VT
Hello Brad
I would post the data to the AID thru Webobs. That way its all in one spot. Jeno can download it from there, and its now in the archive, and all the other observers can also look at it.
Hello Barbara--and all
Unless I hear otherwise, the campaign notice suggested that observations thru April are welcome and useful. I plan to observer some more, when the weather clears.
Gary
Hi, all,
I had good skies last night. Here is about 3.5 hours of data. How much longer do you want us to monitor this star?
Barbara
Hi all- yes, please continue observing (until MWC 560 ceases to be a nighttime object, which will be rather soon)! Sorry for the slow response, I thought I had my account set up to notify me when there was a post here. Interesting results continue to come in---e.g., we just got a detection at 10 GHz with the Very Large Array, signifying at least an order of magnitude increase in radio flux compared to before the outburst in 2014 October.
Hello
I was looking at the light curve for ref object, and this campaign was started when MWC 560 was reported in ourburst at mag 8.8 V on JD xxxx7430. On 7481, (51 days later) it was reported to be 8.7 Vmag. Is this another outburst?
WGR
Gary
Hi Gary.
About MWC 560's recent brightening, I would characterize it as part of the previously reported "outburst". We don't know how long this outburst, or high state, will last. If MWC 560 behaves like CH Cyg -- another jet-producing symbiotic star -- it could even last for more than a year!
As Adrian mentioned, both the radio and soft X-ray flux have increased by more than an order of magnitude in this high state. Since both radio and soft X-ray emission are thought to be associated with the jet from this binary, it looks like the strength of the outflow has increased. When MWC 560 does eventually fade in the optical, we will be very interested in seeing what happens to the optical flickering.
Thanks for your continued attention to this source!
Best,
Jeno
I just wanted to thank Rolf Carstens in New Zealand for the data point on May 14. If MWC 560 is up at night for anyone else, photometry continues to be very useful through the end of the month (i.e., the end of our Swift campaign, and probably our last Very Large Array exposure). We might have no further optical measurements from the professionals as of early-May, since the source is too bright in the optical for Swift, yet I increasingly think the optical might be the best probe of the outburst state. So optical magnitudes or spectra through the end of May, no matter how sporadic, would be precious.
Hi,
I have started observations with snapshots of V0694 Mon in BVI filters.
Unfortunately the comparison stars in the AAVSO sequence are rather faint compared to the brightness of the star (about 8.2 mag in I, 9.4 in V and 9.8 in B).
Regards,
Josch
Hi folks- PI for the X-ray/radio data here. If MWC 560 = V694 Mon is a nighttime object again for anyone, I'd love some photometry (e.g., V band, but any band observed during the early-2016 outburst is fine). Ideally we'd get to check if there's still flickering, but even just one observation would give us a hint as to whether MWC 560 is still in outburst, help us evaluate whether we should apply for more X-ray time and how important continued AAVSO-monitoring is, and aid in the interpretation of radio data still being taken every 1.5 months through January.
A spectrum of, e.g., H-alpha or H-beta would be nice too to check the status of the outflow.
Thanks!
AAVSO Special Notice #429 announces the modification to primarily spectroscopy and continuation of the 2016 campaign on the symbiotic variable V694 Mon (MWC 560). Please see the notice for details and observing instructions.
Many thanks, and good observing,
Elizabeth Waagen, AAVSO HQ
Paper including many of these observations submitted to MNRAS and posted to the arXiv today! https://arxiv.org/abs/1905.02399
Mx. Lucy,
Congratulations on completing the paper. V694 Mon is clearly excited about it: it's currently undergoing another outburst, sitting at just about V=9.
Shawn
To: Dr. Lucy,
Thanks for the citation in your detailed article! I just took (early April19) a Visual-IR spectrum of V0694 Mon before it got too low:
Will download my photometric data to AASVO within the next couple of days.
James
p.s. My dad, was a Columbia College M.S. graduate!