Baryonic Features in the Matter Transfer Function

We provide scaling relations and fitting formulae for adiabatic cold dark matter cosmologies that account for all baryon effects in the matter transfer function to better than 10% in the large-scale structure regime. They are based upon a physically well-motivated separation of the effects of acoustic oscillations, Compton drag, velocity overshoot, baryon infall, adiabatic damping, Silk damping, and cold dark matter growth suppression. We also find a simpler, more accurate, and better motivated form for the zero-baryon transfer function than previous works. These descriptions are employed to quantify the amplitude and location of baryonic features in linear theory. While baryonic oscillations are prominent if the baryon fraction Ωb/Ω0 Ω0h2 + 0.2, the main effect in more conventional cosmologies is a sharp suppression in the transfer function below the sound horizon. We provide a simple but accurate description of this effect and stress that it is not well approximated by a change in the shape parameter Γ.

[1]  A. Kashlinsky,et al.  Large-scale structure in the Universe , 1991, Nature.

[2]  Effect of physical assumptions on the calculation of microwave background anisotropies. , 1995, Physical review. D, Particles and fields.

[3]  William H. Press,et al.  The Cosmological constant , 1992 .

[4]  Jeremiah P. Ostriker,et al.  Unsolved Problems in Astrophysics , 2018 .

[5]  W. Press,et al.  Propagation of adiabatic cosmological perturbations through the ERA of matter-radiation decoupling , 1980 .

[6]  P. Peebles Large-scale background temperature and mass fluctuations due to scale-invariant primeval perturbations , 1982 .

[7]  Martin White,et al.  Acoustic Signatures in the Cosmic Microwave Background , 1996 .

[8]  Carlton M. Baugh,et al.  The three-dimensional power spectrum measured from the APM Galaxy Survey – I. Use of the angular correlation function , 1993 .

[9]  The 4 Year COBE Normalization and Large-Scale Structure , 1996, astro-ph/9607060.

[10]  Sergei F. Shandarin,et al.  The large-scale structure of the universe: Turbulence, intermittency, structures in a self-gravitating medium , 1989 .

[11]  C. Hogan,et al.  Confirmation of High Deuterium Abundance in Quasar Absorbers , 1995, astro-ph/9512004.

[12]  L. Guzzo,et al.  in Wide Field Spectroscopy and the Distant Universe , 1995 .

[13]  A. Szalay,et al.  The statistics of peaks of Gaussian random fields , 1986 .

[14]  J. Silk COSMIC BLACK-BODY RADIATION AND GALAXY FORMATION. , 1968 .

[15]  Max Tegmark Measuring Cosmological Parameters with Galaxy Surveys , 1997, astro-ph/9706198.

[16]  Small scale cosmological perturbations: An Analytic approach , 1995, astro-ph/9510117.

[17]  D. Weinberg,et al.  A Lower Bound on the Cosmic Baryon Density , 1997, astro-ph/9701012.

[18]  Cosmological baryon density derived from the deuterium abundance at redshift z = 3.57 , 1996, Nature.

[19]  D. J. Fixsen,et al.  The Cosmic Microwave Background spectrum from the full COBE FIRAS data set , 1996 .

[20]  J. R. Bond,et al.  Cosmic background radiation anisotropies in universes dominated by nonbaryonic dark matter , 1984 .

[21]  Joel R. Primack,et al.  Dynamical effects of the cosmological constant. , 1991 .

[22]  Alan Dressler,et al.  Large‐Scale Structure in the Universe , 1989 .

[23]  A. Evrard,et al.  The baryon content of galaxy clusters: a challenge to cosmological orthodoxy , 1993, Nature.

[24]  W. Forman,et al.  Cosmological implications of ROSAT observations of groups and clusters of galaxies , 1995 .

[25]  Y. Zeldovich SURVEY OF MODERN COSMOLOGY , 1965 .

[26]  P. J. E. Peebles Primeval adiabatic perturbations - Constraints from the mass distribution , 1981 .

[27]  U. Seljak,et al.  A Line of sight integration approach to cosmic microwave background anisotropies , 1996, astro-ph/9603033.

[28]  Michael A. Strauss,et al.  The density and peculiar velocity fields of nearby galaxies , 1995, astro-ph/9502079.

[29]  P. Peebles,et al.  The Large-Scale Structure of the Universe , 1980 .

[30]  J. A. PeacockS.J. Dodds,et al.  Reconstructing the linear power spectrum of cosmological mass fluctuations , 1993, astro-ph/9311057.

[31]  P. Peebles,et al.  Primeval Adiabatic Perturbation in an Expanding Universe , 1970 .

[32]  J. Holtzman Microwave background anisotropies and large-scale structure in universes with cold dark matter, baryons, radiation, and massive and massless neutrinos , 1989 .

[33]  K. Olive,et al.  Primordial nucleosynthesis redux , 1991 .