Carnegie Mellon University

Astro Lunch

Constraining the effect of reionization on the Lyman-alpha forest

The Lyman-alpha forest is a powerful cosmological probe of the relatively high redshifts (mainly 2<z<5). Recent efforts have been made towards understanding the thermal imprint that reionization leaves in the forest. Modeling and observing this imprint comes with significant technical challenges: the memory from reionization fades away swiftly, hence one must focus on high redshifts; additionally, one must take into account the fact that reionization is an inhomogeneous process while also focusing on what happens at small scales. Because the small scales go fully non-linear prior to reionization, one must be able to resolve their web-like structure. In this talk I will present the strength of the effect due to reionization in the Lyman-alpha forest, and estimate the contribution of this systematic effect to both the 3D and 1D Lyman-alpha power spectrum. Furthermore, I will discuss how this signal can be constrained with the help of the quadrupole of the 21 cm power spectrum.