Sunday, March 26, 2006

Weekly postings

It has been a busy week, though arguably my most productive since Christmas.

I now have Wake's pdl codes running and what's more, I basically understand what they do and how they do it. The result of this is we now, for the very first time (and about 2 years overdue) have a covariance matrix for our 2-point LRG correlation function. This was generated from a jack-knife analysis of 31 sub-samples.

Also, having realised I was working in an Eistein-de Sitter, Omega_M = 1 cosmology, re-calculated the "Sample 8" 2-point and find, as was more expected, that this "redder" sample does have a higher amplitude than the mixed-mashed sample I was using before.

Got lots more to do this week (will have to have a we think and get FOCUSED!) but hopeuflly we'll be going back to daily rather than weekly postings!

Sunday, March 19, 2006

Relaxing weekend in Edinburgh

After the joys (and slight excesses) of St Patrick's Day 2006, I'm in Edinburgh this weekend to relax.

Thursday was essentially a complete write-off but Friday was semi-productive in that Wake helped me out big-style by re-doing a .fits mask for the 2SLAQ LRGs. We're now in the process of getting some fancy jackknife code to run in order to get a co-variance matrix (something I now that we should have done 1.5 years ago). However, my lack of Perl and PDL is hampering me here.

Whatelse? Two good lunchtime talks. One by Rosales (currently Durham) on "The topology of reionization from semi-analytic models of galaxy formation" - looking at how different simulation techniques model the re-ionization history of the Universe. Second was Mountrichas (Durham, another of Shanks's students) on the discrepancies they've been finding between QSO and galaxy clustering between 2QZ and SDSS.

Gonna be another busy, busy week!

Wednesday, March 15, 2006

Deadline Day

Just a quick post.

The AAT deadline come and went and the proposals (ATLAS, AUS LRG, AUS QSO) were submitted. And once everyone had actually read each others cases, we found there was absoultely no conflict between them!

Spinelli (currently Durham), gave a brief but nice overview between the connection of (v. local) starburst, Seyfert 1 and 2 galaxies using x-ray, IRAS infra-red and HST morphology data.

Bruck (Sheffield), "Dark Energy vs. The Rest of the World" has just given us what I thought was a thought provoking talk on scalar fields, couplings, neutrino masses and chameleon fields. I suggested (in private) that since the TT doesn't differentiate much between LCDM and varying neutrino mass models, that a look at the E and B polarization modes might be worthwhile.

On that note, apparently WMAP 2nd Data Release is out tomorrow. 3 years late.

Early mornings

Still a bit jet-lagged, hence the early post.

Yesterday was spent finally getting my Inbox in order. I'm one of those (ever so slightly anal) people who likes to keep all of their received emails while having as few emails in their Inbox folder as possible. This took me upto morning coffee.

After, I tidied up my new "matching" program and started, with Wake, to look at the gri and riz colour trends of our Pilot data. When selecting the z>0.8 galaxies, Wake and I were VERY impressed (and happy) that the points lie right on top off an redshift-tracks given by an easy passive evolution model. Nice.

So, deadline day for the AAT Semester 06B. Most things are done. Shanks has only last night circulated the wiggles proposal but it's looking good. I think the AUS LRG program might get squeezed by it. However, with the AUS QSOs, both make very cool science cases. Really hope this one doesn't get politicked.

Monday, March 13, 2006

The Top Ten at Ten

Observing causes you to do weird things.... There has been a decided lack of posts recently, due to clear skies, the sun of Sydney and the bright lights of Hong Kong but here to make up for it are a list of things we either didn't know, or only suspected just over a couple of weeks ago:

- The riz colour selection works (very) well at picking out redshift > 0.5 LRGs.

- So well in fact, that a mean redshift of nearly redshift = 0.8 was being obtained in some of our fields.

- The riz-selection also works annoyingly well at picking out faint M-stars.

- Shanks's idea of going to a z-band limit (19.5 < z < 20.2) seems to have been inspired.

- The COMBO-17 people basically got it right (on photo-z calculation at least).

- AAOmega works essentially "as it says on the tin".

- The ELG selection, of which I'll need to look into some more, may have the ability to select z~1 galaxies in reasonable (1-2 hour) exposures without the need for GALEX data.

- Thai chicken sandwiches bought from dodgey Mudgee cafes do not agree with me.

- Even with all his annoyances, Shanks just has this ability to really crack me up and go observing with him, Wake, Cannon (AAO), Sharp (AAO) and Stevenson (AAO), was a real treat.

- It is colder in the North-East of England now than in either Hong Kong or Australia and this saddens, annoys and even frustrates me.

So there we have it. Thesis chapters and papers galore!
Should get back into the grove of regular postings - which will be vital with the new competition out there!!

Friday, March 03, 2006

The Romance of Observing

We are collecting photons!!

The weather at Siding Springs Observatory, home of the Anglo-Australian Telescope 3.9m, has dramatically improved over the last 2 or so hours and we are now observing our objects. Or so we think.....

However, clear or cloudy, solid or milky, there is a definite romance to sitting up late at night observing unimagibably far away collections of billions upon billions of stars. Why, here we're not only in the isolation of the New South Wales savanah but also the all but complete desolation that is this tiny rock island in deep space.

It is just coming upto 4am in the morning for me.

New cases of blogs found in Durham...
"a ying and yang blog depictating two mens take on life's cruel twists and turns when their halo simulations/girlfriends don't work out the way they thought they'd programmed them to."
"Ernie and Bert meet Beavis and Butthead on an extraordinary journey discovering the very nature of
space and time."
"The pain of one man's lost love for his office mate. Going to be made into a cowboy movie next year"