The cosmic web can potentially be observed in direct emission through the Lyman-alpha line. While luminous Lyman-alpha emitters are already an established powerful tracer of the matter distribution in the high-redshift universe, the implications of …
The diffuse filaments of the cosmic web can potentially be observed in emission through the Lyman-alpha line. While luminous Lyman-alpha emitters are already an established powerful tracer of the matter distribution in the high-redshift universe, the …
Introduction Lyman-$\alpha$ spectra can provide insights into the small-scale structure and kinematics of neutral hydrogen (HI) within galaxies as well as the ionization state of the intergalactic medium (IGM). The former defines the intrinsic spectrum of a galaxy, which is modified by the latter. These two effects are degenerate: While at low redshifts, double peaked Lyman-$\alpha$ spectra are the norm, we find more and more spectra only showing a red peak at high redshifts.
While Lyman-alpha emitters (LAEs) are already a popular astrophysical and cosmological tracer of the high-z (>2) universe, diffuse Lyman- alpha observations outside of galaxies could become a powerful probe of the filamentary structure of the cosmic …
Below plots show first results of our new radiative transfer code for meshless structures applied to individual halos in the IllustrisTNG simulations.
Lyman-alpha emitter after radiative transfer. Surface brightness in erg/s/cm$^2$/arcsec$^2$. Lyman-alpha emitter after radiative transfer. Artificially lowered neutral hydrogen density by a factor of $10$, revealing the radiative transfer smoothing out the emission from the star forming regions. Surface brightness in erg/s/cm$^2$/arcsec$^2$. The neutral hydrogen column density responsible for scattering out the injected photons in star forming regions.
The dimensionally split power spectrum/two-point correlation are standard tools for constraining the cosmological model from redshift surveys. Given the Lyman-alpha emission line, I will try to motivate what significant distortions from the line's …
Lyman-alpha based emission line surveys are prone to errors in their interpretation due to the complex radiative transfer for this line. We address this issue by running full radiative transfer simulations on the Illustris simulations and generate …