Astronomy and Coffee: March 2010

Application + trip

Just a job application and preparing things for our easter trip to Austria.

Labels: applications, life

Some stuff finished

Mammary gland analysis, finished (so far).

New application for a position, finished, to be sent tomorrow.

Proposal that I'm in but couldn't contribute much to the text finished and submitted.

Labels: applications, mammary_gland_paper

Collecting posts

So, several days.

Gave up writing a new proposal, better advance some stuff to give more background for the next proposal. Of course, not before checking what I needed and I we wanted ...

Successfully modified the ISODENS code I've got from Hugo Capelato (DAS/INPE) to work on the Mac and expanding capabilities to "today's computers". Not, interpreting the results is a whole other story :-)

Mammary gland project almost ready. Gotta write my statistical conclusions.

Wednesday we went to Hofbräuhaus to have dinner with Elif Kutdemir (former Göttingen) that just finished her Ph.D. thesis in Gronningen. It was a nice evening.

Weekend was typically german. We had a really sunny week, that I couldn't enjoy due to too many things to do. Then, friday at 3:00 PM weather changed, windy and rainy ... as it was the whole weekend.

My parents arrived to visit for a month :-)

Labels: hcg_gcs, life, mammary_gland_paper

More on GCs

So! Once the color-color issue was set, candidates were selected on the color-color plot using Harris (1996) Galactic GCs and GALEV SSP models for ages from 2-15 Gyr and a range of metallicities. Locus defined, candidates selected.

Also young star clusters locus defined using GALEV models, from 100 Myr to 1 Gyr.

Now that candidates are selected, density maps to find the GCS center. Options are, they are centered on the galaxies, or they are "common" to the potential (what is the expected considering the distribution of galaxies, UCDs and IGL). To that an kernel density estimator. Tried to find something available on the net, but couldn't (maybe if I look better ...) so using an old code from my old boss and friend Hugo Capelato (DAS/INPE). Making old workstation FORTRAN work on a Mac :-) Also expanding capabilities.

Labels: hcg_gcs

Found!

Despite the 300 thousand things I have to do this week, the whole day was spent on one single, but solution was found and an elegant one :-)

I was worried about the FORS calibration for my images. When I plot a color-color diagram and overplot Harris (1996) Galactic globular clusters on it they are not where my supposed population is.

Option 1 - There's a calibration error. Small errors can't be seen in magnitudes, but popup in colors!

So part of the day was a recalibration effort. FORS transformation equations, surface brightness profiles, very old FORS equations ... confirmed my values. If it's wrong, it's a serious problem ...

Option 2 - Filter differences. Johnson-Cousins to FORS-Bessel filters are supposed to be very close to each other ...

Couldn't find "colors" from Johnson-Cousins to FORS-Bessel filters, so solution was using a SSP model with output in both systems.

Not used to SSP models. Learning how to use Bruzual & Charlot (2003) or any other model would take too much time.

GALEV (Kotulla et al, 2009) turns out to have a great web interface that works very well, at least for simple uses such as my need. Managed to get my magnitudes for a GC with different metallicities and a large range of ages. All that without having to spend time learning details. Of course for something more sophisticated you probably have to really get into it, but for this filter transformation it has worked perfectly.

Got a mean color shift for a 15 Gyr population in metallicities ranging from [Fe/H] = -1.7 to 0.3, applied it to Harris (1996) GCs and VOILA, it all falls into place :-)

One problem less! Now let's move on and with minimal damage (bad calibration would require several modifications, once the right value was found).

Labels: hcg_gcs

For several days!

Just noticed now that several days have passed without posting. Things are quite crazy around here.

So, summarizing including some stuff done during the weekend (which I shouldn't but despaired times call for despaired measures).

Mammary gland projects is going. Still to be done parts 4 and 5.

A lot of discussion about the UCDs paper, even though no feedback from other authors, just the usual ones.

Tweaked the star-galaxy classification to a misclassification ratio of 19%. That includes extended objects in the point-sources list and point-sources left out of the list. That was done in the R FORS image and checked at the ACS image. The ACS image is about a quarter of the FOV, so it's not useful to do the whole classification deal. How this has got to the point where there can be a small error in calibrations. So that's the days task for monday, along with other things.

Other things: prepare a proposal and a job application. All that for friday. Deadline is next week, but my parents will arrive on saturday, and you can imagine what that means :-)

Comment on the weather. This weekend was a typical german weather. Sun until friday, rain on the weekend and a sunny monday :-) At least I took Matheus to the Tagesmutter by bike, like old times. Feeling german again hehehehehehe

I'm also astonished by some stuff I've been reading lately. Can't comment for political reasons, but the only thing that can be said is "the worse bureaucracy is the one we carry inside of us ...".

Labels: hcg_gcs, hcg_ucd, life, mammary_gland_paper

Two days like one :-)

Monday was a very, but very short and slow day. Matheus decided to wake up at 4:30 and finally slept about the time we should be waking up ... so we slept a bit longer.

Sent the paper to the other co-authors, after some small modifications and then organized some info to be "repaired" when it comes back. Small stuff.

Today a failed anaerobic threshold test ... home trainer should have more resistance at the beginning. Again next time.

One more step in the Mammary Gland project. Now gotta write it and do 2 more.

Some playing with colors from SSP models.

Labels: hcg_gcs, hcg_ucd, life, mammary_gland_paper

Friday

So! Friday!

Good thing, this week I managed to train twice, in-door (I know, like a hamster, but there is about 10-15 cm of snow outside).

Retrieved the FLT images from the HST archive ... but still the coordinate transformation doesn't work. It complains about a missing keyword on the header, but doesn't tell me which and why ... dammed pyraf! I'll have to do it brute force, as usual!

UCDs paper is back to me. Gotta finish going thru it, couple of small modifications and distribute it to all the authors on monday.

Tweaking the star-galaxy classificator. Figured out a nice way of defining the tweaking procedure.

Labels: hcg_gcs, hcg_ucd, life

A bit of all

So! Wrote some text describing the analysis so far of the Mammary Gland project, discussed some conclusions for the UCDs paper a we started the idea for the next proposal. Paper will be back today and distributed to all the authors after I fix a couple of references and table captions.

Installed a new version of SciSoft (for OSX) to be sure pyraf would work. Well, it does, but still the function TRAN from STSDAS.DRIZZLE doesn't. It maybe that it's the header of the WI4 image that is not the same as the FLT image. So I already requested the image from STSci's archive, but this may come only tomorrow.

In the mean while I can do something on the ground-based images. So, star-galaxy classification using my old FWHM x Mag method, as in the 2002 paper. On that, it needs some tweaking. On that.

Let's see tomorrow!

Labels: hcg_gcs, hcg_ucd, mammary_gland_paper

Geometric corrections ...

Yesterday more on the mammary gland project. One more step gone. Gotta stop and write what's up so far. 3 steps yet to go and getting more complicated and interesting.

Today GCSs in H90 to complement the UCD's study. Fighting with ACS multidrizzle corrections. Of course there's a pyraf task for that and of course there's something wrong with my pyraf.

The first question is why pyraf? IRAF has been working fine for more than 15 years!

The second question is why ONLY FOR pyraf?

Never managed to make pyraf works! You're told "install scisoft, it comes with it all", no it doesn't! There's always a problem!

Also, I want things on a terminal, so I can do things remotely! I hate windows and GUIs and stuff that doesn't work remotely!

They say Python is the future ... as long as you define which version you're programming to, seems 2.5 is not compatible with 2.6, or so. And as long as you can make it work, mine comes with a "closed package" installation, but still there's something wrong.

Probably gonna have to do things "the hard way", as always. I don't even know why do I bother ...

Labels: hcg_gcs, mammary_gland_paper

Solving small things, again

So! Solving problems like finally registering at the Brazilian consulate and transferring our voting "cards" to Munich. Then to IKEA to buy some stuff we need and never had the will to go as far as IKEA is ... today we did it.

More statistical analysis on the Mammary Gland project.

Labels: life, mammary_gland_paper

Something else

So! To rest my head I started to work on another project. Something on molecular biology :-)

Not Astrobiology, molecular biology, for real! Cancer research!!!

No, I'm not changing areas, not yet. My wife is analyzing a huge chunk of data and if there's something we learn during a PhD is astrophysics is STATISTICS!!! So I'm in charge of the statistical analysis of the data. It's good to deal with something different and it will be nice to be on a non-astronomical paper :-)

I'll finish that on the next couple of days, alongside another important project. An IGL+GCS analysis.

Labels: mammary_gland_paper

Sent "back"

So! No big boring details about the last 3 days.

UCDs paper sent back to Steffen Mieske (ESO-Chile) and Iskren Georgiev (AIfA) with discussion and conclusions drafted. Now their turn to give input on that. This paper is gonna be nice.

Summary of modifications. Text, new text drafted, figures changes, new tables, old tables modified ... so nice work!

In the meanwhile some other stuff to do.

Labels: hcg_ucd

Tables and more tables

Providing some data to Bodo on our low luminosity ellipticals and some drafting on the UCD's paper.

Labels: hcg_ucd, Low luminosity ellipticals

Astronomy and Coffee

Wednesday, March 31, 2010

Application + trip

Tuesday, March 30, 2010

Some stuff finished

Monday, March 29, 2010

Collecting posts

Tuesday, March 23, 2010

More on GCs

Monday, March 22, 2010

Found!

Friday, March 19, 2010

For several days!

Tuesday, March 16, 2010

Two days like one :-)

Friday, March 12, 2010

Friday

Thursday, March 11, 2010

A bit of all

Wednesday, March 10, 2010

Geometric corrections ...

Monday, March 08, 2010

Solving small things, again

Friday, March 05, 2010

Something else

Thursday, March 04, 2010

Sent "back"

Monday, March 01, 2010

Tables and more tables

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