Friday, August 26, 2011

Day 37

Presentation day! I think it went really well and although I was extremely nervous all morning. Everyone else did really well too! We gave Joe, Bob and Bethany their gifts (a photo-shopped picture of all of us) as well as a lava-lamp for Bethany, which I think they will all enjoy! Afterwords we all stuck around and talked for awhile... and planned to go overnight laser-tagging and/or a concert at Darien lake sometime! Also, Jake took the astronomical imaging interns (me, evelyn, matt, alex and jason) out to lunch at applebees, which was fun! I'm sad the internship is over (but happy that the presentation is) because I am going to miss everyone :( and the free food too. This experience was amazing and one that I will never forget!

Day 36

Couldn't come into work today . . .spent the night practicing for tomorrow!

Day 35

Today I showed Joel and Rudy my power point and worked on some of their suggestions for improving it. I don't have much more to do with it though . . . except for practice! I can't come in to work tomorrow either, so I won't be able to practice with everyone else. I am kind nervous for this presentation!

Monday, August 22, 2011

Day 34

Today I came in again around four and showed Joe the rough draft of my powerpoint to make sure it ran well on his computer. Then I continued to work on it. Joel and Rudy gave me some good suggestions for a few of my slides but I still have to go through the whole thing with them. Rudy gave me a link to this website that makes a graph of the optimal viewing times of a star from a certain observatory. It says that it would be best to observe 2M1155-79 from Australia in March . . . but it could be possible as soon as December. Joel is hesitant to write a paper about this until we see if the star has Li absorption, which we will hopefully find out with the visible light spectrum.

Day 33

Today I got here around four in the afternoon and just worked on my powerpoint. I think it is coming along pretty well. I was too tired from soccer to stay for too long so I left around 6:30. I don't think I can make the "practice" presentation on Wednesday... which really worries me because I need all the practice I can get!

Thursday, August 18, 2011

Day 32

In the morning I wrote up a detailed summary of how I found the possible companion stars using Topcat. I also went through the process myself, using the mean proper motions, so I can have the exact results of what you get using them. I've already checked to make sure that the new stars that show up using the mean proper motions aren't emitting x-rays, but I wanted to have the correct lists on file anyways.

Today was the last day I could attend coffee time :( Starting tomorrow, I won't be able to come to work until around four because of double sessions of soccer try-outs. But the strawberry-smoothie I got today was amazing!

In the afternoon, Joel clarified a few background questions I had about companion stars and why they chose V4046 Sgr, MP Mus, T Cha, and TW Hya to study. It is because these stars are around 10 million years old and still have gas in their circumstellar disk, but are just starting to form planets. Usually, stars form planets and lose the gas in their circumstellar disks by 2 to 3 million years old. Therefore, there is a theory that these widely separated companion stars (like TWA 28) were once very close to, in this case, TW Hya, and prevented it from forming planets until now. I made a slide for this info in my powerpoint.

Things are looking good for 2M1155-79, the possible companion for T Cha. Rudy continues to analyze the spectrum and he found a small absorption which is good because that means the star doesn't have a disk (most companions don't). Joel is going to ask his friend in Australia if he will extract the spectrum using his telescope, so we can see if it has Li absorption (indication of a young star).

Wednesday, August 17, 2011

Day 31

Today in the morning I used Topcat again and re-did the search for companion stars to T Cha, and V4046 sgr, because their simbad PM's are significantly different from the mean of their PM's. This time, I matched the PPMXL and UCAC3 lists and then made two more columns on the matched table for the mean pmRA and pmDE. Then, I matched this with the 2mass catalog and limited the stars so that only stars with the mean of their PM's within 15 mas/yr of the binary star's mean PM. I didn't come up with any new star coordinates for T Cha, but I came up with a few for v4046 sgr. However, none are emitting x-rays . . .but it was worth going back to just check and make sure. Also, I finished putting the vectors to represent proper motions on the ds9 x-ray image of MP Mus and it's possible companions. For lunch we had free pizza and watched a movie about entrepreneurs.

In the afternoon, I began by going through Joel's email about how he calculated the bolometric luminosity of our unknown star, which we nicknamed 2M1155-79 (from its 2mass coordinates). The ratio of its x-ray luminosity to its bolometric luminosity is a little large, but not unreasonable, but Joel suspected that this was because the x-ray luminosity (from the spectral fit) was a bit too large. So Rudy re-did the spectral fit and found another x-ray luminosity that is smaller and more reasonable. Now we have officially discarded the RXJ star as a possible companion star and the only one we are still considering is this 2M1155-79. Joel said he might try and get someone to calculate proper motion themselves of T Cha and 2M1155-79 (by comparing recent images with images taken a long time ago). Meanwhile, my job is to write up a detailed summary of how I obtained the data (using Topcat) so that Joel can write a paper on this if he decides to. Also I need try and keep my powerpoint up to date, and decide if I want to present what I did with the planetary nebulae in the beginning of the summer or not . . so much to do, so little time!