Day 169

Monday.  First workday of the year.  Let's go!  (Drinking on New Years Eve seems to have left me somewhat depressed for New Years Day.  I only had a single Bombay Sapphire and half a small glass of Goffel Kölsch.  I ended up wasting 9 hours reading manga.  Manga itself is like a drug to me, that keeps me depressed.  [Good manga, though.  Found Iron Klaus.]  I don't like this effect of drinking.)


1112.6030
Angular clustering of photometrically classified quasar candidates from SDSS NBCKDE
Ivashchenko, Vasylenko, Tugay


Angular clustering of 230k photometrically selected quasar candidates from SDSS NBCKDE catalogue with photoz of 0.8<z<2.2 with 2-pt correlation function.  Power law with theta_0=2.3 arcsec and alpha=0.87.  Agrees with previous results from catalog, as well as x-ray point sources (mostly AGN).  Stellar contamination + 0.1% artifact contamination (SF region of spiral galaxies, diffraction spikes of bright stars).


1112.6040
Direct measurement of the positive acceleration of the universe and testing inhomogeneous models under gravitational wave cosmology
Yagi, Nishizawa, Yoo


(As the title says), 3-5 yr GW observations from neutron-star binaries can enable ruling out LTB void model with monotonically increasing density profile.  [how??]  More powerful than the redshift drift measurement using Lyman alpha forest.


1112.6083
Improved composite spectra of quasars within the H I LyA forest region
Ivashchenko, Sergijenko, Torbaniuk


More accurate approach to the composite spectra construction based on stacking spectra with similar slopes within wavelength range redward of LyA emission line, allows to reduce noise.  Can get better resolusion, found >14 lines in SDSS stacks, 3 found in previous stacks, others found in space-based spectra.  About 20% uncertainty.


1112.6084
Effects of a primordial magnetic field with log-normal distribution on the CMB
Yamazaki, Ichiki, Takahashi


Primordial magnetic fields (PMFs) on the anisotropies of CMB.  PMF has a characteristic scale, reflecting the generation mechanisms, complementary to the power-law spectrum.  Upper limit at k~1e-2.5 Mpc^-1 with B ≤ 3nG.


1112.6091
Detection of CO(J=1-0) emission from barred spiral galaxies at z~0.1
Matsui, Sorai, Watanabe, Kuno


Dim CO signal from 6 out of 9 barred spiral galaxies in z=0.08-0.25 detected at Nobeyama Radio Observatory, dimmest detected to date.  L_IR/L'_CO is a measure of SF efficiency.

1112.6191

The tidal origin of the Magellanic stream and the possibility of a stellar counterpart

Diaz, Bekki

Magellanic stream (MS) is a vast neutral hydrogen structure that trails behind the LMC and SMC.  Reconstruct orbital history in which LMC and SMC have only recently become a binary pair at 2Gyr ago, which disrupted the disk of SMC and thereby create the MS.  The model also reproduces the on-sky bifurcation of the two filaments, and a bound association with the MW is required to reproduce the bifurcation.  Magellanic bridge, the counter-bridge, and two branches of leading H I  also created.

1112.6247

Non-thermal insights on mass and energy flows through the galactic centre and into the Fermi bubbles

Crocker

Construct a simple model of the SF and SNe driven mass and energy flows through the inner ~200 pc (diameter) of the Galaxy, constrained by the non-thermal radio continuum and gamma-ray signals from the region.  Model implies SF rate of 0.04-0.12 Msun/yr, sustained over 10Gyr would fill the 1e9 Msun stellar population of the nuclear bulge.  Mass accreted on GC region at a rate of 0.3 Msun/yr.  SF activity drives an outflow of plasma, CR, and entrained cooler gas.  All material fountains back on the inner Galaxy.  Can explain 1e6 "halo" of molecular gas surrounding the central molecular zone out to 100-200 pc heights.  Presence of relatively pristine, nuclear-unprocessed gas in GC may be explained.  Plasma outflow (from SF...and SNe?) seems to match the Fermi bubble [is the SFR/SNe rate that high?].  Continual SF in the GC over the age of MW kept the SMBH quiescent, preventing it from significantly heating the coronal gas, allowing for the continual accretion of gas on to the disk and the sustenance of SF on much wider scales in the Galaxy.  

* not sure how much I trust this theory, but I'm not an expert.

1112.6249

The Galactic centre - A laboratory for starburst galaxies (?)

Crocker

SF and associated SNe is the ultimate driver of the GC's non-thermal activity.

* same comments as above.


1112.3935
Distances to Galaxies from the Brightest stars in the universe
Kudritzki, Urbaneja


Blue Supergiants (BSGs): brightest stars in the universe with M_V up to -10 mag.  Ideal objects for determination of extragalactic distances, because interstellar extinction and metallicity (which trouble stellar distance indicators) do not affect them--spectral information determines stellar parameters and chemical composition, which are then used to determine accurate reddening and extinction from photometry for each individual object.  Future large telescopes (TMT on Mauna Kea, E-ELT, GAIA mission) allow calibration of the FGLR (flux weighted gravity-luminosity relation) using galactic BSGs for distance calibration.


1112.3937
Interstellar Grains: 50 years on
Wickramasinghe


"Me and Fred Hoyle wrote all these papers together about grains."  Biological provenance of grains.