Day 150

Tuesday.  I left the cosmology lecture half-way yesterday, fed myself, and went straight to bed.  Slept 12 hours, I think.  The IKEA thing must have taken a huge toll on my nerves.  I think I still need to take it easy today.


1112.0566
Surviving the hole I: Spatially resolved chemistry around Sgr A*
Martin, Martin-Pintado, Montero-Castano, Ho, Blundell


Interstellar region within the few central parsecs around the SMBH Sgr A* is composed by a number of overlapping molecular structures, yet subject to one of the most hostile physical environments in the Galaxy.  Observe CN, 13CN, H2CO, SiO, c-C3H2 and HC3N emission at 1.3mm towards the central ~4pc of the Galactic center region.  CN is UV resistant, and traces all previously identified circumnuclear disk (CND) structures; mostly concentrated in optically thick clumps in the rotating filaments around Sgr A*.  H2CO emission traces a shell-like structure, interpreted as the expansion of Sgr A East against the 50km/s and 20km/s giant molecular clouds (GMC's).  Ratios of 12C/13C ~ 15/45 across most of the CND region.  The densest molecular material traced by SiO and HC3N is located in the southern CND.  The observed C3H2/HC3N ratio is an order of magnitude lower tan in Galactic PDRs [?].  Only CN was detected in absorption toward the central region.  Apart from the known narrow line-of-sight absorptons, a 90 km/s wide optically thick spectral feature observed, find evidence for an even wider (>100km/s) feature.  Around 70-75% of the gas mass, concentrated in just the 27% densest molecular clumps, is associated with rotating structures and show evidences of association with each of the arcs of ionized gas in the mini-spiral structure.  Chemical differentiation disentangles many of the overlapping molecular components in this crowded and heavily obscured region.


1112.0567
Lensing of 21-cm Fluctuations by Primordial gravitational waves
Book, Kamionkowski, Schmidt


WL lensing distortion patterns decomposes into curl and curl-free components; gravitational waves induces a curl component in the intensity pattern of 21-cm radiation from the dark ages.  Angular fluctuation in the 21-cm BG extend to very small angular scales, and measurements at different frequencies probe different shells in redshift space.  Can detect tensor-to-scalar ratios conceivably as small as r~1e-9.


1112.0569
Observational evidence for a corrrelation between jet power and black hole spin
Narayan, McClintock


Measure BH spin with continuum-fitting method; show jet in BH binaries correlates with the dimensionless BH spin parameter a*.  


Spectral fit gives an estimate of the radius of the inner edge of the accretion disc.  The BH spin parameter a* is then obtained by assuming that the disk edge is located at the innermost stable circular orbit (ISCO) of the Kerr metric.  The CF method has been developed in detail over the last several years, shown to produce consistent results, supported by numerical simulations.


1112.0679
A description of quasar variability measured using repeated SDSS and POSS imaging
MacLeod, ... Kochaneck, ... Lupton, ... Richards, ... Schneider et al


Provide a catalog and quantitative description and statistical interpretation of the optical continuum variability of quasars.  Distribution of magnitude changes is exponential at large values, and constraints the intrinsic scatter in DRW model parameters among quasars with fixed luminosity, BH mass, and rest wavelength.  All available data consistent with the DRW model as a viable description of the optical continuum variability of quasars on time scales of 1-2000 days in the rest frame.  Use these models to predict the incidence of quasar contamination in transient surveys such as PTF and LSST.


1112.0745
The imporint of the BAO in the cross-correlation of the redshifted HI 21-cm Signal and the Ly-alpha forest
Sarkar, Bharadwaj


Cross-correlation of Ly-alpha forest and redshifted 21-cm emission: mapping out LSS in the post-reioniation era z<6.  Combined with BOSS/BigBOSS where quasar density is 16 deg^2 and 64 deg^2, need radio interferometer with 2m*2m antennas for 21-cm observations of z=2-3.  Need to attain a certain amount of noise level.  4~5 independent radio interferometric array, each containing 400 antennas uniformly sampling all the baselines within 40m will be able to carry out observations in the span for a few years.