Estimating the bispectrum of the Very Small Array data

Sarah Smith; Graca Rocha; Anthony Challinor; Richard A. Battye; Pedro Carreira; Kieran Cleary; Rod D. Davies; Richard J. Davis; Clive Dickinson; Ricardo Genova-Santos; Keith Grainge; Carlos M. Gutierrez; Yaser A. Hafez; Michael P. Hobson; Michael E. Jones; Rudiger Kneissl; Katy Lancaster; Anthony Lasenby; J. P. Leahy; Klaus Maisinger; Guy G. Pooley; Nutan Rajguru; Rafael Rebolo; Jose Alberto Rubino-Martin; Pedro Sosa Molina; Richard D. E. Saunders; Richard S. Savage; Paul Scott; Anze Slosar; Angela C. Taylor; David Titterington; Elizabeth Waldram; Robert A. Watson

doi:10.1111/j.1365-2966.2004.07885.x

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Estimating the bispectrum of the Very Small Array data

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Abstract

We estimate the bispectrum of the Very Small Array data from the compact and extended configuration observations released in December 2002, and compare our results to those obtained from Gaussian simulations. There is a slight excess of large bispectrum values for two individual fields, but this does not appear when the fields are combined. Given our expected level of residual point sources, we do not expect these to be the source of the discrepancy. Using the compact configuration data, we put an upper limit of 5400 on the value of f_NL, the non-linear coupling parameter, at 95 per cent confidence. We test our bispectrum estimator using non-Gaussian simulations with a known bispectrum, and recover the input values.

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Sarah Smith, Graca Rocha, Anthony Challinor, Richard A. Battye, Pedro Carreira, Kieran Cleary, Rod D. Davies, Richard J. Davis, Clive Dickinson, Ricardo Genova-Santos, Keith Grainge, Carlos M. Gutierrez, Yaser A. Hafez, Michael P. Hobson, Michael E. Jones, Rudiger Kneissl, Katy Lancaster, Anthony Lasenby, J. P. Leahy, Klaus Maisinger, Guy G. Pooley, Nutan Rajguru, Rafael Rebolo, Jose Alberto Rubino-Martin, Pedro Sosa Molina, Richard D. E. Saunders, Richard S. Savage, Paul Scott, Anze Slosar, Angela C. Taylor, David Titterington, Elizabeth Waldram, Robert A. Watson. 2004-05-04. Estimating the bispectrum of the Very Small Array data. https://doi.org/10.1111/j.1365-2966.2004.07885.x

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