%0 Generic %1 hazra2019joining %A Hazra, Dhiraj Kumar %A Paoletti, Daniela %A Finelli, Fabio %A Smoot, George F. %D 2019 %K library %T Joining bits and pieces of reionization history %U http://arxiv.org/abs/1904.01547 %X Cosmic Microwave Background temperature and polarization anisotropies from Planck have estimated lower value of the optical depth to reionization ($\tau$) compared to WMAP. A significant period in the reionization history, therefore falls within $6<redshift (z)< 10$ where overlap with the galaxies detected with Hubble Frontier Fields (HFF) program and independent estimation of neutral hydrogen in the inter galactic medium by Lyman-$\alpha$ observations becomes important. This overlap calls for an analysis of cosmic reionization which allows a direct combination of CMB and astrophysical measurements. For the first time we reconstruct reionization histories where the photo-ionization and recombination rates are assumed to be free-form using the Planck CMB (temperature and polarization anisotropies and lensing) and a selection of astrophysical data allowing underlying cosmological parameters to vary. This conservative approach removes model bias, explores degeneracies between reionization and other cosmological parameters in a framework that allows sharp to extended histories of reionization. We find that CMB and astrophysical datasets cannot agree if reionization process is sharp. In this joint estimation, we report a derived conservative constraint $\tau=0.063^+0.005\,+0.02_-0.013\,-0.017$ (68.3\% and 95\% C.L.). We find the duration of reionization, redshift interval between 10\% ionization and nearly complete ionization, to be $2.4<\Delta^reion_z<11.9$ at 95\% C.L. We do not obtain any evidences for double reionization; and within allowed possibilities we find monotonic histories are preferred over other scenarios when CMB and astrophysical data are combined.

@misc{hazra2019joining, abstract = {Cosmic Microwave Background temperature and polarization anisotropies from Planck have estimated lower value of the optical depth to reionization ($\tau$) compared to WMAP. A significant period in the reionization history, therefore falls within $6<{\rm redshift} (z)< 10$ where overlap with the galaxies detected with Hubble Frontier Fields (HFF) program and independent estimation of neutral hydrogen in the inter galactic medium by Lyman-$\alpha$ observations becomes important. This overlap calls for an analysis of cosmic reionization which allows a direct combination of CMB and astrophysical measurements. For the first time we reconstruct reionization histories where the photo-ionization and recombination rates are assumed to be free-form using the Planck CMB (temperature and polarization anisotropies and lensing) and a selection of astrophysical data allowing underlying cosmological parameters to vary. This conservative approach removes model bias, explores degeneracies between reionization and other cosmological parameters in a framework that allows sharp to extended histories of reionization. We find that CMB and astrophysical datasets cannot agree if reionization process is sharp. In this joint estimation, we report a derived conservative constraint $\tau=0.063^{+0.005\,+0.02}_{-0.013\,-0.017}$ (68.3\% and 95\% C.L.). We find the duration of reionization, redshift interval between 10\% ionization and nearly complete ionization, to be $2.4<\Delta^{\rm reion}_{z}<11.9$ at 95\% C.L. We do not obtain any evidences for double reionization; and within allowed possibilities we find monotonic histories are preferred over other scenarios when CMB and astrophysical data are combined.}, added-at = {2019-04-03T06:22:49.000+0200}, author = {Hazra, Dhiraj Kumar and Paoletti, Daniela and Finelli, Fabio and Smoot, George F.}, biburl = {https://www.bibsonomy.org/bibtex/277c89063091f53c2c4379f27e64cdf6a/gpkulkarni}, description = {Joining bits and pieces of reionization history}, interhash = {a716bb1451baebe2babf0befd82bfa48}, intrahash = {77c89063091f53c2c4379f27e64cdf6a}, keywords = {library}, note = {cite arxiv:1904.01547Comment: 7 pages, 4 figures and 1 table}, timestamp = {2019-04-03T06:22:49.000+0200}, title = {Joining bits and pieces of reionization history}, url = {http://arxiv.org/abs/1904.01547}, year = 2019 }