%0 Generic %1 suresh2020unified %A Suresh, Jishnu %A Ain, Anirban %A Mitra, Sanjit %D 2020 %K tifr %T Unified Mapmaking for Anisotropic Stochastic Gravitational Wave Background %U http://arxiv.org/abs/2011.05969 %X A stochastic gravitational wave background (SGWB), created by the superposition of signals from unresolved astrophysical sources, may be detected in the next few years. Several theoretical predictions are being made about the possible nature of anisotropies in the background. Estimating and mapping the intensity across the sky can therefore play a key role in improving our understanding of astrophysical models. Skymaps have been produced in the pixel and spherical harmonic basis for all the data taking runs of the advanced ground-based interferometric detectors. While these maps are being produced with similar algorithms, the underlying algebra and numerical implementations remain different. Which is why there was a need for producing results in both bases. We show that these manifestly redundant methods could be unified to a single analysis in practice as well. We first develop the algebra to show that the results, maps, and noise covariance matrices, in two different bases are easily transformable. We then incorporate both schemes, in the now standard analysis pipeline for anisotropic SGWB, PyStoch. We then show that the transformed results in the pixel and spherical harmonic bases match very well. Thus concluding that a single skymap will be sufficient to describe the anisotropies in a stochastic background. The multiple capabilities of PyStoch will be useful for estimating various measures to characterise an anisotropic background.

@misc{suresh2020unified, abstract = {A stochastic gravitational wave background (SGWB), created by the superposition of signals from unresolved astrophysical sources, may be detected in the next few years. Several theoretical predictions are being made about the possible nature of anisotropies in the background. Estimating and mapping the intensity across the sky can therefore play a key role in improving our understanding of astrophysical models. Skymaps have been produced in the pixel and spherical harmonic basis for all the data taking runs of the advanced ground-based interferometric detectors. While these maps are being produced with similar algorithms, the underlying algebra and numerical implementations remain different. Which is why there was a need for producing results in both bases. We show that these manifestly redundant methods could be unified to a single analysis in practice as well. We first develop the algebra to show that the results, maps, and noise covariance matrices, in two different bases are easily transformable. We then incorporate both schemes, in the now standard analysis pipeline for anisotropic SGWB, PyStoch. We then show that the transformed results in the pixel and spherical harmonic bases match very well. Thus concluding that a single skymap will be sufficient to describe the anisotropies in a stochastic background. The multiple capabilities of PyStoch will be useful for estimating various measures to characterise an anisotropic background.}, added-at = {2020-11-12T07:07:23.000+0100}, author = {Suresh, Jishnu and Ain, Anirban and Mitra, Sanjit}, biburl = {https://www.bibsonomy.org/bibtex/2321fc59b125105b5737b410fe5e2fbe6/citekhatri}, description = {Unified Mapmaking for Anisotropic Stochastic Gravitational Wave Background}, interhash = {2b28054aca6eb9f5d346e02c82d8bed4}, intrahash = {321fc59b125105b5737b410fe5e2fbe6}, keywords = {tifr}, note = {cite arxiv:2011.05969Comment: 8 pages, 9 figures}, timestamp = {2020-11-12T07:07:23.000+0100}, title = {Unified Mapmaking for Anisotropic Stochastic Gravitational Wave Background}, url = {http://arxiv.org/abs/2011.05969}, year = 2020 }