Cosmology with intensity mapping techniques using atomic and molecular lines

Abstract

We present a systematic study of the intensity mapping (IM) technique using updated models for the different emission lines from galaxies. We identify which ones are more promising for cosmological studies of the post reionization epoch. We consider the emission of Lyα, Hα, Hβ, optical and infrared oxygen lines, nitrogen lines, CII and the CO rotational lines. We show that Lyα, Hα, OII, CII and the lowest rotational CO lines are the best candidates to be used as IM probes. These lines form a complementary set of probes of the galaxies emission spectra. We then use reasonable experimental setups from current, planned or proposed experiments to assess the detectability of the power spectrum of each emission line. Intensity mapping of Lyα emission from z = 2 to 3 will be possible in the near future with HETDEX, while farinfrared lines require new dedicated experiments. We also show that the proposed SPHEREx satellite can use OII and Hα IM to study the large-scale distribution of matter in intermediate redshifts of 1 to 4. We find that submilimeter experiments with bolometers can have similar performances at intermediate redshifts using .

Small-scale Intensity Mapping: Extended Halos as a Probe of the Ionizing Escape Fraction and Faint Galaxy Populations during Reionization

“…We therefore assessed the contribution of nebular emission produced "in-situ" in satellite sources clustered around the central galaxy in Mas-Ribas et al (2017). These satellites would be too faint to be resolved individually, but their integrated emission may be detectable, analogous to the method of "intensity mapping" (see Fonseca et al 2017 and references therein), but here applied to much smaller scales. In general, these models matched the Lyα profiles observed by Matsuda et al (2012) and Momose et al (2014) at z=3.1 remarkably well for different clustering prescriptions.…”

Extreme spheres: counts-in-cells for 21cm intensity mapping

“…Another interesting direction could be to employ the accurate analytical, beyond lognormal model for onepoint statistics of dark matter (Uhlemann et al 2016) to probe high-redshift astrophysics. Intensity mapping can be done with lines different from the 21cm spin-flip line of neutral hydrogen, which are sensitive to different astrophysical processes (Suginohara et al 1999;Fonseca et al 2017) and can probe various environments such as hotter hydrogen gas (Lyα), ionised regions (C II) or cool dense molecular gas (CO). In this context, Breysse et al (2017) introduced the probability distribution of voxel intensities and demonstrated its application to CO emission finding constraints on the luminosity function of the order of 10 percent.…”

Constraining the expansion history and early dark energy with line intensity mapping

“…Choosing a model in the middle of the distribution, we find that measuring the "C16" model [60] , L16 [37], P18 [58], P13B [50], C11 [36]. For models providing only a brightness temperature (I), we assumed a bias b = z [45]. Model amplitudes in µK 2 are converted to specific intensities in (W/m 2 /Hz/sr) 2 along the top axes; since the conversion is frequency-dependent, the scales change for each panel.…”

“…In this model, an early dark energy component with density Ω ede approximates a cosmological constant with w ≈ −1 at , S15 [59], S16 [41], C16 [60]. For models providing only a brightness temperature (I), we assumed a bias b = z [45]. Model amplitudes in (Jy/sr) 2 are converted to (W/m 2 /Hz/sr) 2 along the top axes.…”