Friday, August 31, 2012

They'll make a spectroscopist out of me yet

Putting together one of three (at least) proposals for WHT observations on La Palma. Already had some success obtaining Dutch time (going observing in December, woop!) but this time round, I'm aiming for some much more riskier idea that Torsten had and we are now developing.
And it involved that ol familiar: the WHT/ISIS spectrograph. I have not worked with that kind of data since my master's thesis. It looks like this particular instrument and setup will just nicely fit the bill.

Now to convince a casual onlooker that I know a thing or two about spectra and AGNs.

Thursday, August 30, 2012

Memory Leak

I suspect something has been updated in my python installation (possibly by yours truly) but a pice of code I've been relying on has started memory leaking like I have HD to spare.
Optemizing this python code had been on my "well someday" list anyway so here goes. Python code is nearly never optimized. If you wanted it to run superfast, you don't code in python. You code in python because it takes an afternoon of your time. If the runtime is then till the next day, who cares?

It better run a little more efficient. I need to run a local Galaxy Catalog through it. Time to optimize this puppy.

Wednesday, August 29, 2012

Saggitarius Again

For a while I had been struggling with a strange overdensity of M-dwarfs in the BoRG survey. It felt as a strange coincidence or a fault in the identification process. Thanks to Bob Benjamin, I finally got a positive ID on what could be causing the overdensity: the Saggitarius stream. Even the distances of the bulk of M-dwarfs in that particular field fit nicely with the typical distance to Saggitarius dwarf: 20-25 kpc.

To me this revealed a big gap in our knowledge of the Milky Way. Suppose you are a extragalactic astronomer and find some odd over-density of point sources. Before you write the paper on some z~8 cluster, you need to check there is no stellar stream surrounding the MW of any kind in the vicinity. But a decent map collating all the known streams, arms, satellites and globular clusters and their tidal features etc does not exist yet. My solution: email Bob but there has to be a better one.