%0 Generic %1 fonseca2020measuring %A Fonseca, José %A Liguori, Michele %D 2020 %K library %T Measuring ultra-large scale effects in the presence of 21cm intensity mapping foregrounds %U http://arxiv.org/abs/2011.11510 %X HI intensity mapping will provide maps of the large scale distribution of neutral hydrogen in the universe. These are prime candidates to be used to constrain primordial non-Gaussianity using the Large Scale Structure of the Universe as well as to provide further tests of Einstein's theory of Gravity. But HI maps are contaminated by foregrounds which can be several orders of magnitude above the cosmological signal. Here we quantify how degenerated are the large-scale effects ($f_NL$ and GR effects) with the residual foregrounds. We conclude that a joint analyses does not provide a catastrophic degradation of constraints and provides a framework to determine the marginal errors of large scale effects in the presence of foregrounds. Similarly, we concluded that the macroscopical properties of the foregrounds can be measured with high precision. Notwithstanding, such results are highly dependent on accurate forward modeling of the foregrounds, which incorrectly done catastrophically bias the best fit values of cosmological parameters, foregrounds' parameterizations, and large-scale effects.

@misc{fonseca2020measuring, abstract = {HI intensity mapping will provide maps of the large scale distribution of neutral hydrogen in the universe. These are prime candidates to be used to constrain primordial non-Gaussianity using the Large Scale Structure of the Universe as well as to provide further tests of Einstein's theory of Gravity. But HI maps are contaminated by foregrounds which can be several orders of magnitude above the cosmological signal. Here we quantify how degenerated are the large-scale effects ($f_{\rm NL}$ and GR effects) with the residual foregrounds. We conclude that a joint analyses does not provide a catastrophic degradation of constraints and provides a framework to determine the marginal errors of large scale effects in the presence of foregrounds. Similarly, we concluded that the macroscopical properties of the foregrounds can be measured with high precision. Notwithstanding, such results are highly dependent on accurate forward modeling of the foregrounds, which incorrectly done catastrophically bias the best fit values of cosmological parameters, foregrounds' parameterizations, and large-scale effects.}, added-at = {2020-11-24T07:22:36.000+0100}, author = {Fonseca, José and Liguori, Michele}, biburl = {https://www.bibsonomy.org/bibtex/2001f3591c49f87bbb384ed0f4c332a24/gpkulkarni}, description = {Measuring ultra-large scale effects in the presence of 21cm intensity mapping foregrounds}, interhash = {938b501a65bc9726667b315b9492f720}, intrahash = {001f3591c49f87bbb384ed0f4c332a24}, keywords = {library}, note = {cite arxiv:2011.11510Comment: 13 pages, 3 figures, 4 tables. Comments welcome}, timestamp = {2020-11-24T07:22:36.000+0100}, title = {Measuring ultra-large scale effects in the presence of 21cm intensity mapping foregrounds}, url = {http://arxiv.org/abs/2011.11510}, year = 2020 }