Day 92

Wednesday.  I hope I will find a flat today.  I will take Filomena's flat if I don't like the ones I hear from, or see, today.


1109.5688
Intracluster medium of the merging cluster Abell 3395
Lakhchuaura, Singh, Saikia, Hunstead


* what it says.


1109.5690
A filamentation instability for streaming cosmic rays
Reville, Bell


Demonstrate that CRs form filamentary structures in the precursors of SNe remnant shocks due to their self-generated magnetic fields.  CR filamentation results in growth of a long wavelength instability, and naturally couples the rapid non-linear amplification on small scales to larger length scales.  Confirmed by a hybrid of MHD and particle simulations.  Resulting large scale magnteic field may facilitate scattering of high energy CRs as required to accelerate protons beyond the knee in the CR spectrum at SNe remnant shocks.  Filamentation far upstream of the shock may also assist in the escape of CRs from the accelerator.


* cool, on the origin of CRs.


1109.5691
Sample variance in photometric redshift calibration: cosmological biases and survey requirements
Cunha, Huterer, Busha, Wechsler


Use N-body+photometric galaxy simulations to examine the impact of sample variance of spectro redshift samples on the accuracy of photo-z determination and calibration of photo-z errors.  Estimate bias in cosmological parameter constraints from WL and derive requirements on the spectro follow-up for 3 different photo-z algorithms, chosen to span the range of algorithms available.  Find sample varinace much more relevant for photo-z error calibration than from photo-z training; follow-up requirements are similar for different algorithms.  Spectro sample [presumably with cosmic variance?] can be used for training of photo-zs and error calibration without incurring additional bias in the cosmological parameters.  Provide guide for observing proposals for spectroscopic follow-up; e.g., 150 patches of sky with Magellan (1/8 sqdeg field and 400 galaxies per patch) for calibrating DES, 75 nights of observation.  Requirements can be reduced by an order of magnitude if the redshift distribution of the overall sample can be estimated by some other technique.


* cool.  Good to check these things for the survey.