Sunday. Ran to the church this morning, and said hi to Pers on the way down. I have 7 items on my to-do list today (this is item #2). We'll see how far I get.
1111.0644
The cosmic web and galaxy evolution around the most luminous X-ray cluster: RXJ1347.5-1145
Verdugo, Lerchster, Boehringer, Hildebrandt, Ziegler, Erben, Finoguenov, Chon
Study LSS and their galaxy content around the most X-ray luminous cluster known, at z=0.45. Use ugriz CFHT MEGACAM photometry and VIMOS VLT spectroscopy to identify structures around the cluster on a scale of 20x20 Mpc^2. Construct maps of the galaxy distribution and the fraction of blue galaxies. Study photometric properties as a function of environment, traced by galaxy density. ID group candidates based on galaxy overdensities. Use available GALEX NUV imaging to identify strong unobscured SF galaxies. Find: LSS around the cluster extends in the NE-SW direction for at least 20 Mpc, in which most of the group candidates are located; fraction of blue galaxies (Fblue) is a function of galaxy number density, but the bulk of the trend is due to galaxies belonging to massive systems. Fraction of UV-bright galaxies also function of environment, but relative numbers compared to the blue population appears to be constant [for the blue case, the segregation was stronger in high density regions] regardless of environment. These UV emitters also have similar properties at all galaxy densities, indicating that the transition between galaxy types occurs in short time-scales [what's the time scale? transition from what to what? from UV to blue?]. Candidate galaxy groups show a large variation in galaxy content and Fblue in those groups display little dependence with galaxy density. May indicate possible differences in theier evolutionary status or the processes that are acting in groups are different than in clusters. The LSS around rich clusters are dynamic places for galaxy evolution. In the case of RXJ1347 the transformation may start within infalling groups to finish with the removal of cold gas once galaxies are accreted in massive systems.
1111.0932
A measurement of secondary CMB anisotropies with 2 years of SPT observations
Reichardt, Shaw, Zahn, ... Carlstrom, ... George, ...Holzapfel, ... Knox, Lee, ..., Mohr, ... Ruhl, ... Shirokoff et al
Present the first 3-frequency SPT CMB power spectra. Band powers presented cover 2000<ell<9400 in frequency bands of 95, 150, and 220 GHz. These frequencies and angular scales: combination of primary CMB anisotropy, tSZ and kSZ, radio galaxies, CIB contributes to the signal. Combine Planck and SPT data at 220 GHz to constrain amplitude and shape of the CIB power spectrum, find strong evidence for non-linear clustering [these are z~2 galaxies, so that makes sense]. Explore the SZ results using a variety of cosmological models for the CMB and CIB anisotropies, and find them to be robust with one exception: allowing for spatial correlations between the tSZ and CIB significantly degrades the SZ constraints. Neglecting this potential correlation, find the tSZ power at 150 GHz and ell=3000 to be 3.65 pm 0/69 muK^2, and set an upper limit on the kSZ power to be less than 2.8 muK^2 at 95% CL. When correlation between tSZ and CIB allowed, constrain a linear combination of tSZ and kSZ power, [some value], consistent with earlier measurements. Use the measured tSZ power and an analytic tSZ model calibrated with simulations to determine sigma8 = 0.807pm0.016. Modeling uncertainties involving the astrophysics of the intracluster medium rather than the statistical uncertainty in the measured band powers are the dominant source of uncertainty in sigma8. We also place an upper limit on the kSZ power produced by patchy reinoization, companion paper uses these limits to constrain the reionization history of the universe.
1111.0648
New Zealand pathway towards Asia-Pacific and global e-VLBI research and development
Gulyaev, Natusch, Weston, Thomasson
Outline VLBI research and development of NZ's participation in Australasian, Asia-Pacific, and global scales. Real-time e-VLBI is a vital part of NZ's capability development towards the SKA. NZ's radio astronomy serve as model for the engagement in mega-Science and e-Science by resource-limited institutions and nations. Perspectives for collaboration between NZ and Thailand in the field of radio astronomy included.
Lunch Colloquium (9 Nov, 12:45)
Project BEACON (or, how I learned to stop worrying and love general relativity)
Paulo Freire
Project BEACON: funded with 1.9 Million Euro Consolidator award from European Research Council. Theoretical motivation and aims: with binary pulsar timing, carry out the most stringent test of gravitational theories. Building an ultra-broadband receiver and coherent dedispersion system for the Effelsberg telescope, for better timing precision. Preliminary results show: even at start of the project, already exclude all natural versions of the TVS theories of gravity (relativistic version of MOND). These preliminary findings indicate that, within the experimental precision, GR provides the correct description of gravity and that the rotation curves of galaxies are due to some new form of matter, not incompleteness in our knowledge of gravity.
* I have to go see this, and witness the potential bloodbath. Why is MOND still a relevant topic in this institute?!
1111.0052
General requirements on matter power spectrum predictions for cosmology with WL tomography
Hearin, Zentner, Ma
WL shear correlation constrain w, but photoz constitutes a major source of uncertainty; interpretation requires NL physics of gravitational collapse. When photoz uncertainty is taken into account, the requirements on the level of precision in the prediction for matter power spectrum are more stringent than previously thought. Including degree-scale galaxy clustering statistics in a joint analysis with WL not only strengthens the survey constraining power by 20% but also changes calibration demands: using galaxy clustering information significantly relaxes the demands on the photoz calibration. Compare calibration requirements to the contemporary state-of-the-art in photometric redshift estimation and predictions of the power spectrum and suggest strategies to utilize forthcoming data optimally.
1111.0099
Baryons in the outskirts of the X-ray brightest galaxy cluster
Simionescu, Allen, Mntz, Werner, Takei
Suzaku observation of faint cluster outskirts of Perseus; evidence for clumpy distribution of the gas. Important for understanding the physics of the ongoing growth of clusters from the surrounding cosmic web.
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