Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Harmonic analysis of isotropic fields on the sphere with arbitrary masks   Obtaining constraints from the largest scales of a galaxy survey is
challenging due to the survey mask allowing only partial measurement of large
angular modes. This scatters information from the harmonic-space 2-point
function away from the diagonal and introduces coupling between modes. In this
paper, we derive a custom eigenbasis adapted to any particular survey geometry
so that all information is retained on the diagonal. At the expense of a
somewhat complex pixel- and selection-function-window, the result is a diagonal
2-point function with a simple shot noise, and a diagonal covariance matrix in
the case of a Gaussian random field. We derive the basis on the surface of a
sphere, and we use it to construct a 3D spherical Fourier-Bessel power spectrum
estimator assuming a survey geometry that is separable in the angular and
radial directions.

25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga