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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 03. März 2015, 21:18:24 PM 
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Registriert: 31. Juli 2006, 16:43:32 PM
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Not too many months, though. The run ended about 1.5 years ago. A detailed analysis needs some time. Emily will present first results in June in Potsdam (http://www.astro.physik.uni-potsdam.de/~wr2015/), I presume, working hardly towards a paper.

Cheers, Thomas


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 29. Mai 2015, 22:08:28 PM 
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Registriert: 20. Mai 2015, 21:54:39 PM
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Hi everyone,

I have some preliminary results to share with you all from our 2013 campaign. I still have some work left to do on the data, but so far everything has been going well! I really appreciate your patience and understanding. As some of you may already know, I am a student and have been taking classes as well as working on this data set. We still have a few things to figure out, but these are the results we have so far (which are very exciting, I think!). I have only been focusing on one of the stars for my master's work (WR134) and will be focusing on the other two stars (WR135 and 137) for my PhD.

At the bottom, I have included a link to view the poster I created for the recent CASCA (Canadian Astronomical Society) meeting I attended. Unfortunately the file is too large to add to the thread itself, but you don't need a Dropbox account to view the poster. I will include a few quick notes on each figure:

Figure 1: Displays all of the spectra (393) we were able to use from the campaign on WR134. We have a total of 9 observers/locations who contributed. We just recently received new data from Grant Hill a few days ago, who works at the Keck Observatory in Hawaii. We have not incorporated this data yet since it was only recently sent to us but we plan on using it for our final analysis.

Figure 2: This is not a plot of the entire data set, but of a 10-day time span where the emission line showed the strongest variability. The average spectrum was calculated and subtracted from the entire data set, giving a nice residual plot. Higher intensities indicate where the CIR is present in the line. You can see in this figure that the 2.25-day period comes out beautifully.

Figure 3: We used the average spectrum in order to create a 2-D Scargle periodogram. This determines where the frequency (1/period) is the strongest in the emission line. The harmonic to the frequency, along with both of their aliases can be seen as well.

Figure 4: A plot of the skewness calculations verses time. Calculating the skewness of the line helps us determine how much the emission line changes , or how much it is "skewed", with respect to the central wavelength (5411 Angstroms). From this plot, it can be seen that the period comes out the strongest in this calculation around 2.255 and lasts for around 40 days. It is not shown on the poster, but we used many other calculations to verify this period.

Figure 5: After determining the period of the CIR (2.255), we were able to organize the spectra in terms of phase. Similarly to Figure 2, we organized the difference spectra by phase and created a difference image for every 5 cycles (similar to the black and white images of Figure 5). These images were cross-correlated with the central image (dotted line) in order to determine how the CIR changes over a long period of time. It can be seen with this plot that there is a time-coherency of around 40 days (which came out in Figure 4 as well). So it takes around 40 days (or 18 cycles) for the CIR to appear and then disappear once again.

Figure 6: We created new difference images that were organized by phase, but instead of having 5-cycle sections we used 40-day sections. A total of 5 difference images were created in order to determine how the CIR changes with this time coherency. Only 4 are shown here due to space constraint. We compared these images with models created by Dessart & Chesneau. The model indicates that when two CIRs cross in our line of sight, that area should be much brighter. We can see this effect in our images, indicating that there is more than one CIR in the wind of this star.

I find these results very very exciting and hopefully we can continue to learn what exactly we are seeing with this star. We still have some work to do before we can make any concrete conclusions, but we are working on those next. I am currently trying to calculate the kinematics of the central CIR. Once we do this, the central CIR can be "subtracted" from the spectra and we will be able to see for sure if there are other CIRs in the wind. I will be presenting these results next week in Potsdam (I'm very excited to visit Germany again!) and will begin writing my thesis as soon as I get home. Everyone who has participated in the campaign will receive an email if/when I publish the final results. And I will definitely keep everybody on the forum updated as well.

Again, I thank you for being patient with this. It was very challenging to reduce all of the data from different observers, and there were many kinks I had to work out with the Teide data, which took a great deal of time. It is a habit of mine (and I'm sure with other students) to wait until most of the difficult work is finished before publishing their results. I want to make sure I can work out all of the problems correctly before showing other people the data. I wouldn't want to misinform anybody due to rushing the reduction process. Please feel free to ask me any questions and I will try to answer them the best I can. And if anybody wants my work email, feel free to ask and I will send you that as well. :)

Thanks again to everybody who contributed to this campaign. These results are very exciting and we are learning many new things about this star in the process. We couldn't have gotten this far without you and I really appreciate all of the work you all have put into this campaign.

Thank you so much for your patience!
Emily Aldoretta

link:
https://www.dropbox.com/s/7qag0x0lrz4at ... 5.pdf?dl=0


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 30. Mai 2015, 12:29:00 PM 
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Registriert: 19. Oktober 2012, 07:39:49 AM
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:( :( Hi Emily:

I can never open the link you gave.

Dong Li


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 30. Mai 2015, 21:36:57 PM 
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Registriert: 20. Mai 2015, 21:54:39 PM
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Hi all,

Sorry for the issues. I uploaded the poster to my website, so hopefully this will work better. It's very difficult to shrink this PDF and have a good enough resolution to see all of the figures in good detail. If this doesn't work please let me know and I will try to figure something else out.

Thanks,
Emily

http://www.astro.umontreal.ca/~emily/CA ... er2015.pdf


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 30. Mai 2015, 23:20:12 PM 
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Registriert: 23. Februar 2008, 19:33:52 PM
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Zitat:
:( :( Hi Emily:

I can never open the link you gave.

Dong Li
Hi Dong Li!
Those of us who receive this via email will have the link "spoiled". The link will be abbreviated with "..." in the middle, so it will not work. You must follow the link to the forum, and then click on the link here.

(I am, however, not able to log in to my dropbox account, and apparently this is needed) :(

_________________
Fil.


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 31. Mai 2015, 05:22:10 AM 
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Registriert: 19. Oktober 2012, 07:39:49 AM
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:-* Filipe , thank you for your explanation! Now I can download the PDF from Emily.

Wow~~ :shock: the result is fantastic Emily. Great work!

Cheers,
Dong Li


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 31. Mai 2015, 09:54:52 AM 
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Registriert: 19. August 2006, 11:45:20 AM
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Hi Emily,

thank you for presenting your splendid results. A lot of work!

Cheers
Berthold


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 02. Juni 2015, 11:45:57 AM 
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Hi all, presently Emily and me are in Potsdam on a professional WR workshop. http://www.astro.physik.uni-potsdam.de/~wr2015/ Emily presented her great results already and she got very positive reactions. Our main goal to see if the Corotating Interaction Regions come and go periodically has been successfully answered. Their 40 days period of occurence was a matter of debate. Is it because of hot spots on the surface or is it a resonance effect due to non-radial pulsations? The whole issue is so exciting and reflects our success! YOU ARE PARt OF IT!

Cheers, Thomas


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 11. Februar 2016, 18:23:51 PM 
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Registriert: 20. Mai 2015, 21:54:39 PM
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Hi everyone!!

I'm sorry for taking long on posting the final results of this campaign. I have finally submitted my master's thesis and it was accepted at the end of December!! :D Since my thesis has been finished, I have been working on reformating the paper for publication and just completed this today. I have just sent out an email to all of the professional astronomers that were involved in the project and once I have reviewed their comments I will be sending out the final version to everybody (including you all) before I submit to Monthly Notices of the Royal Astronomical Society. So if you were involved in the project, pleaset be on the look-out for an email in the next few weeks!! I have to wait and hear back from 18 people before we can move to the next step, so only a little more patience is needed! Again, thank you all for your hard work on this project. The results are spectacular and we've learned so much about the winds of these massive stars because of you! If you would like to read my thesis (section 2 is the results of the project), here is a link:

http://www.astro.umontreal.ca/~emily/Al ... emoire.pdf

It's a very large file, so be aware when you go to open it. Once the published version has been accepted, I will post a link to that on here as well. And feel free to ask me any questions you may have about the results!! The published version will differ slightly than what I have in my thesis. It is much more condensed and has a slightly different layout, but the results are the same. Enjoy!!!! :D

Cheers,
Emily


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 12. Februar 2016, 04:20:54 AM 
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:D Emily:

Great job~~~ Congratulation from CHINA ;D ~~ Hope we can work together again in the future.

Dong Li


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 12. Februar 2016, 18:02:50 PM 
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Hi Emily,

Congratulations for your great work! Even if I cannot understand all details of your big paper, it is very interesting to me! By the way, my name ist "Berthold Stober" not "Stöber"! Please could you correct this?!

best regards
berthold


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 15. Februar 2016, 21:57:46 PM 
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Registriert: 20. Mai 2015, 21:54:39 PM
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Hi Berthold,

Yes I have corrected! I apologize for the mistake! I will be sending you (and Dong Li, as well as the other amateurs who contributed) an email in about two weeks after I hear back from all of the professionals and make their corrections. Be on the look-out for my email!! :D

Best regards,
Emily


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 15. Februar 2016, 23:42:57 PM 
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Registriert: 25. Oktober 2006, 23:43:13 PM
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Hi Emily,

Congratulations on completing the thesis !

In "section 2.4.3 Other Amateur Data" you suggest that the variation in resolution between the spectra from observers using the LHIRES III was due to variations in spectrograph focus. I suspect the difference is more likely to be due to the slit width used. The LHIRES has standard slit widths of 19,23 and 35um. The resolution in my spectra closely matches the expected resolution for a well focused spectrum using the 35um slit, based on the FWHM of the IS Na D lines for example. I suspect the reason Mike Potters spectra were at higher resolution may have been because he used the 23um slit instead of the 35 um slit used by the other observers. This would explain the higher resolution (R~7500 compared with ~5300 in table 2 II)

Cheers
Robin


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 16. Februar 2016, 00:00:30 AM 
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Also I used the LHIRES III for these observations, not the ALPY 600 (Table 2 I)

Cheers
Robin


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 Betreff des Beitrags: Re: Teide 2013 WR campaign
BeitragVerfasst: 16. Februar 2016, 17:44:38 PM 
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Registriert: 20. Mai 2015, 21:54:39 PM
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Hi Robin,

Thank you for letting me know about the LHIRES III. I've made the change in the version of the paper that is going to be published. Unfortunately, the version that is going to be sent to MNRAS had to be drastically cut, so the majority of the observation section was condensed and/or removed. I was not aware that Mike had used a different slit size, which of course would give his spectra a much higher resolution. He also used a slightly larger telescope (C14 rather than C11) which would also affect the data quality as well. I'm sure it was a combination of both. But that's of course my mistake, I should have contacted him personally and asked him which slit he used. I will make the appropriate corrections to the thesis version that I have posted up in the forum. Also, expect an email from me at the end of the month. Please feel free to send lots of comments when I send out the MNRAS version. It's quite difficult to find these small mistakes when you have been looking at this project/paper for two years! Fresh eyes always help. :D

Cheers,
Emily


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