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Updated: Jul 28, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Constraints on galaxy bias, matter density, and primordial non-Gaussianity from the PSCz galaxy redshift survey
H A Feldman1, J A Frieman, J N Fry
1Department of Physics & Astronomy, University of Kansas, Lawrence 66045, USA. feldman@ukans.edu
Abstract:
We compute the bispectrum for the IRAS PSCz catalog and find that the galaxy distribution displays the characteristic signature of gravity. Assuming Gaussian initial conditions, we obtain galaxy biasing parameters 1/b(1) = 1.20(+0.18)(-0.19) and b(2)/b(2)(1) = -0.42+/-0.19, with no sign of scale-dependent bias for k < or = 0.3h Mpc(-1). These results impose stringent constraints on non-Gaussian initial conditions. For dimensional scaling models with chi(2)(N) statistics, we find N > 49, which implies a constraint on primordial skewness B3 < 0.35.
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