%0 Generic %1 mitra2015cosmic %A Mitra, Sourav %A Choudhury, T. Roy %A Ferrara, Andrea %D 2015 %K Planck reionization %T Cosmic reionization after Planck %U http://arxiv.org/abs/1505.05507 %X Cosmic reionization holds the key to understand structure formation in the Universe, and can inform us about the properties of the first sources, as their star formation efficiency and escape fraction of ionizing photons. By combining the recent release of Planck electron scattering optical depth data with observations of high-redshift quasar absorption spectra, we obtain strong constraints on viable reionization histories. We show that inclusion of Planck data favors a reionization scenario with a single stellar population. The mean $x_HI$ drops from $\sim0.9$ at $z=10.6$ to $\sim0.02$ at $z=5.8$ and reionization is completed around $5.8złesssim9.3$ (2-$\sigma$), thus indicating a significant reduction in contributions to reionization from high redshift sources. We can put independent constraints on the escape fraction $f_esc$ of ionizing photons by incorporating the high-redshift galaxy luminosity function data into our analysis. We find that $f_esc$ increases moderately from $9\%$ to $20\%$ in the redshift range $z=6-9$. Such result is however consistent at 2-$\sigma$ confidence level with a non-evolving escape fraction.

@misc{mitra2015cosmic, abstract = {Cosmic reionization holds the key to understand structure formation in the Universe, and can inform us about the properties of the first sources, as their star formation efficiency and escape fraction of ionizing photons. By combining the recent release of Planck electron scattering optical depth data with observations of high-redshift quasar absorption spectra, we obtain strong constraints on viable reionization histories. We show that inclusion of Planck data favors a reionization scenario with a single stellar population. The mean $x_{\rm HI}$ drops from $\sim0.9$ at $z=10.6$ to $\sim0.02$ at $z=5.8$ and reionization is completed around $5.8\lesssim z\lesssim9.3$ (2-$\sigma$), thus indicating a significant reduction in contributions to reionization from high redshift sources. We can put independent constraints on the escape fraction $f_{\rm esc}$ of ionizing photons by incorporating the high-redshift galaxy luminosity function data into our analysis. We find that $f_{\rm esc}$ increases moderately from $9\%$ to $20\%$ in the redshift range $z=6-9$. Such result is however consistent at 2-$\sigma$ confidence level with a non-evolving escape fraction.}, added-at = {2015-05-22T09:43:36.000+0200}, author = {Mitra, Sourav and Choudhury, T. Roy and Ferrara, Andrea}, biburl = {https://www.bibsonomy.org/bibtex/266e0636f288b751b59698fc127c3c898/miki}, description = {[1505.05507] Cosmic reionization after Planck}, interhash = {7e8eb4a51a4335ab4348034a6f638d4a}, intrahash = {66e0636f288b751b59698fc127c3c898}, keywords = {Planck reionization}, note = {cite arxiv:1505.05507Comment: 5 pages, 3 figures, submitted to MNRAS Letter}, timestamp = {2015-05-22T09:43:36.000+0200}, title = {Cosmic reionization after Planck}, url = {http://arxiv.org/abs/1505.05507}, year = 2015 }