Engineering topics

Maniyar, Abhishek S.

Publications and source records attributed to Maniyar, Abhishek S..

3 records

DOE OSTI2024

Constraining cosmology with the CMB × line intensity mapping-nulling convergence

Lensing reconstruction maps from the cosmic microwave background (CMB) provide direct observations of the matter distribution of the universe without the use of a biased tracer. Such maps, however, constitute projected observables along the line of sight that are dominated by their low-redshift contributions. To cleanly access high-redshift information, Maniyar et al., [Phys. Rev. D 105, 083509 (2022)] showed that a linear combination of lensing maps from both CMB and line intensity mapping (LIM) observations can exactly null the low-redshift contribution to CMB lensing convergence. In this paper we explore the scientific returns of this nulling technique. Here, we show that LIM-nulling estimators can place constraints on standard Λ⁢CDM plus neutrino mass parameters that are competitive with traditional CMB lensing. Additionally, we demonstrate that as a clean probe of the high-redshift universe, LIM nulling can be used for model-independent tests of cosmology beyond Λ⁢CDM and as a probe of the high-redshift matter power spectrum.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2024

New Probe of the High- z Baryon Acoustic Oscillation Scale: BAO Tomography with CMB × LIM -Nulling Convergence

Standard rulers such as the baryon acoustic oscillation (BAO) scale serve as workhorses for precision tests of cosmology, enabling distance measurements that probe the geometry and expansion history of our Universe. Aside from BAO measurements from the cosmic microwave background (CMB), most standard ruler techniques operate at relatively low redshifts and depend on biased tracers of the matter density field. In a companion paper, we explored the scientific reach of nulling estimators, where CMB lensing convergence maps are cross-correlated with linear combinations of similar maps from line intensity mapping (LIM) to precisely null out the low-redshift contributions to CMB lensing. We showed that nulling estimators can be used to constrain the high redshift matter power spectrum and showed that this spectrum exhibits discernible BAO features. Here we propose using these features as a standard ruler at high redshifts that does not rely on biased tracers. Forecasting such a measurement at z ~ 5, we find that next-generation instruments will be able to constrain the BAO scale to 7.2% precision, while our futuristic observing scenario can constrain the BAO scale to 4% precision. In conclusion, this constitutes a fundamentally new kind of BAO measurement during early epochs in our cosmic history.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2024

The star formation, dust, and abundance of galaxies with unWISE -CIB cross-correlations

Here, the cosmic infrared background (CIB) is the accumulated infrared (IR) radiation mainly from interstellar dust heated up by early stars. In this work, we measure the cross-correlation between galaxies from the unWISE catalog and the CIB maps from the Planck satellite to simultaneously constrain the cosmic star formation rate (SFR), dust spectral energy distribution (SED), and the halo occupation distribution (HOD). The unWISE galaxy catalog is divided into three tomographic bins centered at z ~ 0.6, 1.1, 1.5, and the CIB maps are at 353, 545, and 857 GHz. We measure the cross-correlations between these galaxy samples and CIB maps and get a 194σ signal within an angular scale 100 < ℓ < 2000, from which we constrain two CIB halo models from previous literature and one new model. The SFR, SED, and HOD model parameters are constrained consistently among the three models. Specifically, the dust temperature at z = 0 is constrained T 0 = $21.14^{+1.02}_{-1.34}$ K, which is slightly lower than T 0 = 24.4±1.9 K measured by the Planck collaboration. The halo mass that gives the most efficient star formation is around 10 11.79 $^{+0.73}_{-0.86}$ M ⊙ . From the model parameters, combined with the SFR density at z = 0 synthesized from multi-wavelength observations, we break the degeneracy between SED and SFR and recover the cosmic star formation history that is consistent with multi-wavelength surveys. We also constrain the graybody SED model in agreement with previous measurements from infrared flux stacking. From the HOD constraints, we derive an increasing trend of galaxy linear bias along redshifts that agrees with the results from cross- and auto-correlation with unWISE galaxies. This study indicates the power of using CIB-galaxy cross-correlation to study star formation, dust, and abundance of galaxies across cosmic time.

79 ASTRONOMY AND ASTROPHYSICS↗