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OLIMPO is a proposed Antarctic balloon-borne Sunyaev-Zel'dovich effect (SZE) imager to study gas dynamics associated with structure formation along with the properties of the warm-hot intergalactic medium (WHIM) residing in the connective filaments. During a 25 day flight OLIMPO will image a total of 10 z∼0.05 galaxy clusters and 8 bridges at 145, 250, 365, and 460 GHz at an angular resolution of 1.0′–3.3′. The maps will be significantly deeper than those planned from CMB-S4 and CCAT-P, and will have excellent fidelity to the large angular scales of our low-z targets, which are difficult to probe from the ground. In combination with X-ray data from eROSITA and XRISM we will transform our current static view of galaxy clusters into a full dynamic picture by measuring the internal intra-cluster medium (ICM) velocity structure with the kinematic SZE, X-ray spectroscopy, and the power spectrum of ICM fluctuations. Radio observations from ASKAP and MeerKAT will be used to better understand the connection between ICM turbulence and shocks with the relativistic plasma. Beyond the cluster boundary, we will combine thermal SZE maps from OLIMPO with X-ray imaging from eROSITA to measure the thermodynamics of the WHIM residing in filaments, providing a better understanding of its properties and its contribution to the total baryon budget. [ABSTRACT FROM AUTHOR]

MAXIMA is a balloon-based bolometric experiment to measure the temperature anisotropy of the CMB over spatial frequency range 36≤l≤1235. The MAXIMA-1 flight produced a 124 square degree temperature anisotropy map with a beam diameter of 10 arcmin. These data have been used to produce a power spectrum which is in excellent agreement with data from BOOMERANG and DASI, but covers a wider range of angular scales. The MAXIMA power spectrum is consistent with the prediction of Λ CDM models and has been used to constrain cosmological models. The MAXIMA experiment is described and an outline is given of the contents and significance of papers written by the MAXIMA team. MAXIMA is being modified to measure the polarization anisotropy of the CMB. A brief description of this MAXIPOL experiment is also given. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning exercise. Experiments planned and underway are prepared to study the cosmological neutrino background in detail via its influence on distance-redshift relations and the growth of structure. The program for the next decade described in this document, including upcoming spectroscopic galaxy surveys eBOSS and DESI and a new Stage-IV CMB polarization experiment CMB-S4, will achieve sigma(sum m_nu) = 16 meV and sigma(N_eff) = 0.020. Such a mass measurement will produce a high significance detection of non-zero sum m_nu, whose lower bound derived from atmospheric and solar neutrino oscillation data is about 58 meV. If neutrinos have a minimal normal mass hierarchy, this measurement will definitively rule out the inverted neutrino mass hierarchy, shedding light on one of the most puzzling aspects of the Standard Model of particle physics --- the origin of mass. This precise a measurement of N_eff will allow for high sensitivity to any light and dark degrees of freedom produced in the big bang and a precision test of the standard cosmological model prediction that N_eff = 3.046., Astronomy

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of CMB and large-scale structure (LSS) experiments are poised to test the leading paradigm for these earliest moments---the theory of cosmic inflation---and to detect the imprints of the inflationary epoch, thereby dramatically increasing our understanding of fundamental physics and the early universe. A future CMB experiment with sufficient angular resolution and frequency coverage that surveys at least 1% of the sky to a depth of 1 uK-arcmin can deliver a constraint on the tensor-to-scalar ratio that will either result in a 5-sigma measurement of the energy scale of inflation or rule out all large-field inflation models, even in the presence of foregrounds and the gravitational lensing B-mode signal. LSS experiments, particularly spectroscopic surveys such as the Dark Energy Spectroscopic Instrument, will complement the CMB effort by improving current constraints on running of the spectral index by up to a factor of four, improving constraints on curvature by a factor of ten, and providing non-Gaussianity constraints that are competitive with the current CMB bounds., Astronomy

We discuss the status of the data obtained from the first two flights of the MAXIMA balloon-borne experiment. MAXIMA is sensitive to CMB fluctuations on angular scales from 10 arcmin to 5 degrees. The instrument uses a 16 element bolometric array with 3 frequency bands centered at 150, 240, and 410 GHz. An angular power spectrum of the CMB anisotropy has been obtained from the data of the first flight, MAXIMA-1, which shows a peak at ℓ ∼ 220 of 78 ± 6μK and an amplitude varying between 40 μK and 50 μK from 400 < ℓ < 785 [1]. During a second flight (MAXIMA-2), in 1999, we mapped an additional 225 square degree region of the sky, nearly twice the area of MAXIMA-1. Data from MAXIMA-1 are consistent with adiabatic inflationary models with the total energy density, Ω = 1.0[SUP+0.15,SUB-0.3], the total baryon density, Ω[SUBb]h[SUP2] = 0.03 ± 0.01, and the spectral index of the initial power spectrum, n[SUBs] = 1.08 ± 0.1 [2]. Limits are quoted at the 95% confidence level. Data from MAXIMA have been combined with those from LSS observations, SNIa observations, COBE, and BOOMERanG, and have been used for cosmological parameter estimation [3]. MAXIMA data can be obtained at http://cfpa.berkeley.edu/maxima. [ABSTRACT FROM AUTHOR]