Day 1409

Friday.

1805.03672
Verifications of scaling relations useful for the intrinsic alignment self-calibration
Meng, Yu, Zhang, Jing

IA is a major challenge of WL cosmology.  To alleviate this problem, Zhang 2010 proposed a self-calibration method, independent of IA modeling.  This proposal relies on several scaling relations between 2pt clustering of IA and matter/galaxy fields, which were previously only tested with analytical IA models.  In this paper, these relations are tested comprehensively with a N-body sim of 2073^3 sim particles and box size 600 Mpc/h.  They are verified at the accuracy level of O(1)% over angular scales and source redshifts of interest.  Further confirm that these scaling relations are generic, insensitive to halo mass, weighting in defining halo ellipticities, photo-z error, and mis-alignment between galaxy ellipticities and halo ellipticities.  Also present and verify 3 new scaling relations on the B-mode IA.  These results consolidate and complete the theory side of the proposed self-calibration technique.


1805.04004
The dearth of difference between central and satellite galaxies I. Perspectives on star formation quenching and AGN activities
Wang, .. Mo, ... van den Bosch, et al

Investigate the quenching properties of central and satellite galaxies, utilizing the halo masses and central-satellite identifications from the SDSS galaxy group catalog of Yang+.  Find that the quenched fractions of centrals and satellites of similar stellar masses have similar dependence on host halo mass.  The similarity of the two populations is also found in terms of sSFR and 4000A break.  The quenched fractions of centrals and satellites of similar masses show similar dependencies on bulge-to-total light ratio, central velocity dispersion and halo-centric distance in halos of given halo masses.  The prevalence of optical/radio-lound AGNs is found to be similar for centrals and satellites at given stellar masses.  All these findings strongly suggest that centrals and satellites of similar masses experience similar quenching processes in their host halos.   Discuss implications of the results for the understanding of galaxy quenching.