Separating intrinsic alignment and galaxy-galaxy lensing
نویسندگان
چکیده
منابع مشابه
Intrinsic/extrinsic Density-ellipticity Correlations and Galaxy-galaxy Lensing
We compute both extrinsic (lensing) and intrinsic contributions to the (galaxy-)density-ellipticity correlation function, the latter done using current analytic theories of tidal alignment. The gravitational lensing contribution has two components: one is analogous to galaxy-galaxy lensing and the other arises from magnification bias – that gravitational lensing induces a modulation of the gala...
متن کاملIntrinsic Galaxy Alignments and Weak Gravitational Lensing
Gravitational lensing causes background galaxy images to become aligned, and the statistical characteristics of the image alignments can then be used to constrain the power spectrum of mass fluctuations. Analyses of gravitational lensing assume that intrinsic galaxy alignments are negligible, but if this assumption does not hold, then the interpretation of image alignments will be in error. As ...
متن کاملIntrinsic galaxy shapes and alignments II: Modelling the intrinsic alignment contamination of weak lensing surveys
Intrinsic galaxy alignments constitute the major astrophysical systematic of forthcoming weak gravitational lensing surveys but also yield unique insights into galaxy formation and evolution. We build analytic models for the distribution of galaxy shapes based on halo properties extracted from the Millennium Simulation, differentiating between earlyand late-type galaxies as well as central gala...
متن کاملTheoretical Estimates of Intrinsic Galaxy Alignment
It has recently been argued that the observed ellipticities of galaxies may be determined at least in part by the primordial tidal gravitational field in which the galaxy formed. Long-range correlations in the tidal field could thus lead to an ellipticityellipticity correlation for widely separated galaxies. We present a new model relating ellipticity to angular momentum, which can be calculate...
متن کاملReducing and constraining the intrinsic galaxy alignment contamination to weak lensing measurements
We present a method for removal of the contaminating effects of intrinsic galaxy alignments, in measurements of cosmic shear from multicolour weak lensing surveys. The method down-weights pairs which are likely to be close in three dimensions, based on spectroscopic or photometric redshifts. Results are dramatic: the intrinsic contamination of the low-redshift Sloan photometric redshift survey ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2012
ISSN: 1475-7516
DOI: 10.1088/1475-7516/2012/05/041