Exoplanet XO-1b in CrB

Very nice to see this light curve indeed!
It must be very cool to see the curve dip indicating the
planet is passing in front as predicted.
I assume there is some place one can download data
for estimates of transits?

How much of a drop in mag are you recording here?
it seems to be around 0.06 of a mag?

Does the data come in in real time or are
there calculations required after the event to confirm the pass?

Amazing work as always.

Barberskum wrote:

Very nice to see this light curve indeed!
It must be very cool to see the curve dip indicating the
planet is passing in front as predicted.

Once you get into this type of work, it really becomes very addictive. Unfortunately I am more than half way through the available list of candidates and, as such, a good portion of this work will come to an end. I plan to repursue a number of efforts from last year but this time with my ST-10XME since it produces much cleaner results owing to its greater sensitivity and well-depth.

I assume there is some place one can download data
for estimates of transits?

I personally work off the published papers which always give you the julian date at midtransit as well as the period of revolution for the planet and the transit duration. With these three bits of information, you can predict as far into the future involving future transits as you wish.

As far as online sources are concerned, you also have the TransitSearch website at transitsearch.org/ .

How much of a drop in mag are you recording here?
it seems to be around 0.06 of a mag?

Oh no, it is MUCH less than that. For this particular exoplanet, the transit depth is 17 mmag or 17 parts per 1000. In other words, 0.017 magnitudes. Given the host star is mag 11.190 preingress, it dips to 11.207 during midtransit.

These exoplanets typically involve transit depths of 6 to 20 mmag. There is a very small number which exceed 20 mmag but certainly still represent faint changes. I think the greatest depth I have read about is around 32 mmag (one of the Corot finds).

Does the data come in in real time or are
there calculations required after the event to confirm the pass?

The light curve is produced at the end of the session. However, I do process the subs +/- 30 min of the predicted ingress during my session out of shear anxiety and interest.

Amazing work as always.

Thanks!

Anthony.

ayiomamitis wrote:

Dave_Lillis wrote:

Thats very serious stuff there Anthony, 1 down 51 to go!

Excuse me?

We have nineteen captures so far and counting: www.perseus.gr/Astro-Photometry.htm ... with two complete scopes up and running, I sincerely hope to knock all of them off this year.
Anthony.

oops, I didnt realise, so you're well on your way.
Fab stuff !

Anthony - I checked out the graph - did you consider that your measured egress time seems a little earlier than the prediction?

I'm no mathematician/statistician but might it be worth looking into?
Dave

dmcdona wrote:

Anthony - I checked out the graph - did you consider that your measured egress time seems a little earlier than the prediction?

I'm no mathematician/statistician but might it be worth looking into?

Hi Dave,

Your observation is something which is already being looked into and there seems to be a possible sinusoidal pattern in these deviations between predicted and observed ingress/egress times using a variety of results and which mine also confirms.

This is the beauty about amateur participation in such work where multiple measurements and participation allows for more thorough analysis and refinements which otherwise would take much longer.

Last night I went after TrES-4b in Her and I fell flat on my face for the second time with this particular exoplanet. Although I can easily capture the 10.2 mmag transit, the light curve is quite messy using Lum (first effort) and Infrared (second effort) filters with high standard errors. I do have a very good S/N ratio and a flux which exceeds 200,000 ADU for both my exoplanet hosting star as well as for my comparison and check stars.

To add insult to injury, one has only two to three efforts each year to capture the complete transit.

Patience as usual ... I will get it!

Anthony.

If your data helps confirm the theory, its another good-news story of pro-am collaboration and of your own tireless work in this area. Well, apart from screwing up TrES-4b

Patience is a virtue, and you have it bucket-loads! Keep it going and keep it coming!

Dave