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arXiv · 1806.04015

The Galaxy Power Spectrum and Bispectrum in Redshift Space

Vincent Desjacques·Donghui Jeong·Fabian Schmidt
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Abstract

We present the complete expression for the next-to-leading (1-loop) order galaxy power spectrum and the leading-order galaxy bispectrum in redshift space in the general bias expansion, or equivalently the effective field theory of biased tracers. We consistently include all line-of-sight dependent selection effects. These are degenerate with many, but not all, of the redshift-space distortion contributions, and have not been consistently derived before. Moreover, we show that, in the framework of effective field theory, a consistent bias expansion in redshift space must include these selection contributions. Physical arguments about the tracer sample considered and its observational selection have to be used to justify neglecting the selection contributions. In summary, the next-to-leading order galaxy power spectrum and leading-order galaxy bispectrum in the general bias expansion are described by 22 parameters, which reduces to 11 parameters if selection effects can be neglected. All contributions to the power spectrum can be written in terms of 28 independent loop integrals.

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Vincent Desjacques, Donghui Jeong, Fabian Schmidt. 2018-06-11. The Galaxy Power Spectrum and Bispectrum in Redshift Space. https://doi.org/10.1088/1475-7516%2F2018%2F12%2F035

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