Dark Matter Science in the Era of LSST Bechtol, Keith; Abazajian, Kevork N; Ali-Haïmoud, Yacine ...
arXiv (Cornell University),
03/2019
Paper, Journal Article
Odprti dostop
Astrophysical observations currently provide the only robust, empirical measurements of dark matter. In the coming decade, astrophysical observations will guide other experimental efforts, while ...simultaneously probing unique regions of dark matter parameter space. This white paper summarizes astrophysical observations that can constrain the fundamental physics of dark matter in the era of LSST. We describe how astrophysical observations will inform our understanding of the fundamental properties of dark matter, such as particle mass, self-interaction strength, non-gravitational interactions with the Standard Model, and compact object abundances. Additionally, we highlight theoretical work and experimental/observational facilities that will complement LSST to strengthen our understanding of the fundamental characteristics of dark matter.
We present the current state of models for the \(z\sim3\) carbon monoxide (CO) line-intensity signal targeted by the CO Mapping Array Project (COMAP) Pathfinder in the context of its early science ...results. Our fiducial model, relating dark matter halo properties to CO luminosities, informs parameter priors with empirical models of the galaxy-halo connection and previous CO(1-0) observations. The Pathfinder early science data spanning wavenumbers \(k=0.051\)-\(0.62\,\)Mpc\(^{-1}\) represent the first direct 3D constraint on the clustering component of the CO(1-0) power spectrum. Our 95% upper limit on the redshift-space clustering amplitude \(A_{\rm clust}\lesssim70\,\mu\)K\(^2\) greatly improves on the indirect upper limit of \(420\,\mu\)K\(^2\) reported from the CO Power Spectrum Survey (COPSS) measurement at \(k\sim1\,\)Mpc\(^{-1}\). The COMAP limit excludes a subset of models from previous literature, and constrains interpretation of the COPSS results, demonstrating the complementary nature of COMAP and interferometric CO surveys. Using line bias expectations from our priors, we also constrain the squared mean line intensity-bias product, \(\langle{Tb}\rangle^2\lesssim50\,\mu\)K\(^2\), and the cosmic molecular gas density, \(\rho_\text{H2}<2.5\times10^8\,M_\odot\,\)Mpc\(^{-3}\) (95% upper limits). Based on early instrument performance and our current CO signal estimates, we forecast that the five-year Pathfinder campaign will detect the CO power spectrum with overall signal-to-noise of 9-17. Between then and now, we also expect to detect the CO-galaxy cross-spectrum using overlapping galaxy survey data, enabling enhanced inferences of cosmic star-formation and galaxy-evolution history.
