TESS Science Team Meeting #23 - Shared screen with speaker view
Sam Quinn
As Dave mentioned, if you have a question during the presentation, you can type your question in chat and I can read them for the speaker to answer. If a question comes to you during the Q&A, feel free to raise your hand, or if there’s a lull, you can unmute yourself.
Courtney McIntosh
Where is NGTS located?
peter mccullough
Atacama near VLT
David Anderson
Paranal in Chile @Courtney
David Anderson
(same site as the ESO VLT and near to the ESO ELT)
Pablo Lewin
NGTS how are you combining the data from so many telescopes at once? (No time for answers now I know but maybe later?)
Sam Gill
It depends on the need exactly, but most of the time we fit the lightcurve from each telescope seperatly and combine once zero-points are known. Ed Bryant, a Ph.D. student at Warwick does a lot of our bright-star work.
Ares Osborn
per David Ciardi's question, we have inclinations of the planets in the TOI-431 system as: b - 84.5 degrees; c - <86.35 degrees (in order to not transit); and d - 89.7 degrees
David R. Ciardi
Thanks … I just couldn't quite remember.
Ares Osborn
no problem! :)
Douglas Caldwell
Do you have enough RV data to set upper limits on the masses of the potential 2 planets at the proposed longer periods?
Steven Villanueva
Which, if any, of the possible transiting planets are expected to re-transit in the extended mission?
Lauren Weiss
“Do you have enough RV data to set upper limits on the masses of the potential 2 planets at the proposed longer periods?” —> Good question! Yes, and the best constraints will come from combining the HIRES and HARPS-N RVs.
Gaia Lacedelli
"Do you have enough RV data to set upper limits on the masses of the potential 2 planets at the proposed longer periods?" ==> yes, we were actually able to determine the masses of the 2 external period planet
Gaia Lacedelli
"Which, if any, of the possible transiting planets are expected to re-transit in the extended mission? " ==> The planets at 10.8 d, 16 d and 25 d are expected to re-transit, but unfortunately not the planet at ~77 d
Eric Jensen
Is there any archival photometry (WASP, KELT) that might have detected earlier transits?
David R. Ciardi
I've already asked questions so feel free to skip: is there a common period between the rv and photometric rotation period?
Maximilian N. Günther
How good is HARPS with dealing with such bright stars? Might the BIS correlation be an effect of being too bright?
peter mccullough
Saturation might be an issue too
Joey Rodriguez
Yeh, probably saturated in KELT unless it is near the edge of the frame.
Coel Hellier
What is the transit depth of HD128582?
Hugh Osborn
I did start looking, but it was saturated in WASP. And at 500ppm, it’s unlikely to cause any observable signal.
Belinda Nicholson
@David Ciardi: There is a similarity in the timescale of variation in the TESS light curve and the rvs.
Belinda Nicholson
@ Max Guenther: The HARPS data a nice, but also there are too few of them to say much. They do show the strongest correlation with BIS, but you have to be careful with small no. stats with that.
Belinda Nicholson
@ Coel Hellier: the transit depth is d = 0.0006 mag
Joey Rodriguez
Unfortunately, that depth most ground based surveys won’t provide any additional constraints.
Peter Wheatley
@Belinda: if the new RV data could be taken during the next TESS observations, maybe the stellar activity could be decorrelated using the photometry?
Simon Albrecht
For Ashley: Nice results! How different would the ecc. distributions of the giant and dwarf hosts look like if you would to plot them over period and instead of a/R?
Ashley Chontos
@ Simon Albrecht: Thank you! The period distribution also appears to have a similar trend but these are still preliminary orbits. We also haven’t added giants in from https://arxiv.org/pdf/1805.11620.pdf but we are looking to compare to this population as well
Luke Bouma
@Ann Marie: thanks for this talk! Quick question: what approach are you taking to ensure that the periodic “rotation” signals aren’t from unresolved binary blends?
Belinda Nicholson
@Peter Wheatley Having simultaneous TESS photometry would definitely be a big help. It will still be challenging though, as our current activity mitigation methods don’t handle well having activity evolution on timescales shorter than the periods we are looking for.
Josh Schlieder
David, we are seeing your presenter view
Ann Marie Cody
@LukeBouma - that is a good question. In general, the Herbigs are much brighter than any companions, and so the variability signal should in principle drown out variability of blended neighbors. But you are right that any signals (rotation or otherwise) need to be followed up at higher spatial resolution.
Ashley Chontos
Which is WILD to think
Ashley Chontos
Luke Bouma
@Ann Marie – got it! Makes sense. Thank you!
Erica Gonzales
Was KOI-5 in the False Positive Catalog? For David
David R. Ciardi
Erica … KOI 5.01 and 5.02 are not in the FP catalog
Eric Jensen
@David Ciardi - what are your best-estimate semimajor axes for the two stellar companions?
Erica Gonzales
Thanks, David!
David R. Ciardi
Eric: 15 and 75 AU (projected)
Eric Jensen
Can you correct the inner one based on orbital solution?
David R. Ciardi
yes … that is the astrometry+rv fit … I have the period, but would need to look up the au
Eric Jensen
Thanks, David!
peter mccullough
How many pixels show a detectable step function?
Douglas Caldwell
And is the step always positive?
Rahul Jayaraman (he/him)
@Peter — we find that around 10-20% of the light curves we generate per CCD show this step function, not sure how that translates into a pixel percentage/count. These are assigned high probabilities by the CNN - on the order of 0.8 or higher.
Rahul Jayaraman (he/him)
@Douglas - not necessarily! We are also finding ones with 3 or even 4 levels of the “step function.”
David R. Ciardi
Eric: 12.3 au (max sep: 37 mas, min sep: 7mas)
Jon Jenkins
Rahul: It would be helpful if you could document these step discontinuities and pass the information along to tesshelp@bigbang.gsfc.nasa.gov. A ticket will be filed and will help us coordinate our analysis and response back to you and the community.
Coel Hellier
@Anna Payne: what is the V mag of that ASAS-SN object?
Eric Jensen
@Anna Payne - it looks like the X-ray brightening lagged the UV and optical; is that understood?
Anna Payne
@ Michael — the blackbody fits show ~10,000K
Anna Payne
@ Coel — the V mag is ~14.6
Anna Payne
@ Eric — the x-ray evolution is very interesting and the x-ray flux did not correlate but we are not sure if it is a lag or just a different type of behavior. I’m currently looking into the X-ray evolution more and didn’t have time to discuss it here, but I will be observing the X-rays with NICER/Chandra/Swift.
Eric Jensen
Interesting, thanks!
David R. Ciardi
Michelle - can you comment on how well this works in the crowded regions vs non-crowded regions?
David R. Ciardi
Nice talk - thank you.