Detecting the signature of helium reionization through 3HeII 3.46cm line-intensity mapping

Abstract

Helium reionization is the most recent phase change of the intergalactic medium, yet its timing and main drivers remain uncertain. Among the probes to trace its unfolding, the 3.46 cm hyperfine line of singly-ionized helium opens the study of helium reionization to upcoming radio surveys. We aim to evaluate the detectability of the 3.46,cm signal with radio surveys and the possible constraints it can place on helium reionization, in particular whether it can distinguish between early and late helium reionization scenarios. Moreover, we perform a comprehensive study of the advantages of single-dish vs. interferometric setup. Using hydrodynamical simulations post-processed with radiative transfer, we construct mock data cubes for two models of helium reionization. We compute the power spectrum of the signal and forecast the signal-to-noise ratio for SKA-1 MID, DSA-2000, and a PUMA-like survey, in both observational setups. The two scenarios produce distinct power spectra, but the faintness of the signal, largely caused by weak coupling between the spin temperature and the kinetic temperature in low-density regions of the IGM, combined with high instrumental noise, makes detection very difficult within realistic integration times for current surveys. A PUMA-like survey operating in single-dish mode could, however, detect the 3.46 cm signal with an integrated signal-to-noise ratio of a few in < 1000 h in both scenarios. Distinguishing helium reionization scenarios with 3.46 cm line-intensity mapping therefore remains challenging for current facilities. Our results, however, indicate that next-generation, high-sensitivity surveys with optimized observing strategies, especially when combined with complementary probes of the IGM, could begin to place meaningful constraints on the timing and morphology of helium reionization.

12 pages, 8 figures, submitted to A&A

References in corpus (21)

• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• BAT AGN Spectroscopic Survey - V. X-ray properties of the Swift/BAT 70-month AGN catalog
• A Comprehensive Study on Galaxies at z~9-16 Found in the Early JWST Data: UV Luminosity Functions and Cosmic Star-Formation History at the Pre-Reionization Epoch
• The Final SDSS High-Redshift Quasar Sample of 52 Quasars at z>5.7
• Late-time cosmology with 21cm intensity mapping experiments
• Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
• A consistent and robust measurement of the thermal state of the IGM at $2\le z\le 4$ from a large sample of Ly$\alpha$ forest spectra: Evidence for late and rapid HeII reionization
• CEERS Key Paper VI: JWST/MIRI Uncovers a Large Population of Obscured AGN at High Redshifts
• The History and Morphology of Helium Reionization
• Modeling the neutral hydrogen distribution in the post-reionization Universe: intensity mapping
• The 21 Centimeter Forest
• AGN-driven helium reionization and the incidence of extended HeIII regions at redshift z>3
• Detecting Helium Reionization with Fast Radio Bursts
• The space density of ultra-luminous QSOs at the end of reionization epoch by the QUBRICS Survey and the AGN contribution to the hydrogen ionizing background
• Dating individual quasars with the HeII proximity effect
• Probing large scale filaments with HI and ${}^3$HeII
• The HI-halo mass relation at redshift $z\sim 1$ from the Minkowski functionals of 21 cm intensity maps
• The ALMA Spectroscopic Survey in the HUDF: Constraining cumulative CO emission at $1\lesssim z\lesssim 4$ with power spectrum analysis of ASPECS LP data from 84 to 115 GHz
• Impact of $1/f$ noise on cosmological parameter constraints for SKA intensity mapping
• Eddington accreting Black Holes in the Epoch of Reionization
• Probing the high-z IGM with the hyperfine transition of ${}^3$He${}^{+}$