J. R. Bond
A5032242568- Cosmology and Gravitation Theories
- Galaxies: Formation, Evolution, Phenomena
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Dark Matter and Cosmic Phenomena
- Scientific Research and Discoveries
- Superconducting and THz Device Technology
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Computational Physics and Python Applications
- Black Holes and Theoretical Physics
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- History and Developments in Astronomy
- Astrophysical Phenomena and Observations
- Particle physics theoretical and experimental studies
- Relativity and Gravitational Theory
- Astro and Planetary Science
- Neutrino Physics Research
- Climate variability and models
- Geomagnetism and Paleomagnetism Studies
Canadian Institute for Theoretical Astrophysics
2015-2024
University of Toronto
2015-2024
Canadian Institute for Advanced Research
1989-2017
University of Chicago
2014
The University of Texas at Austin
2008
AlbaNova
2008
Stockholm University
2008
National Radio Astronomy Observatory
2004
Institut d'Astrophysique de Paris
2003
University of Cambridge
1983-2003
view Abstract Citations (3327) References (46) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Statistics of Peaks Gaussian Random Fields Bardeen, J. M. ; Bond, R. Kaiser, N. Szalay, A. S. A set new mathematical results on the theory random fields is presented, and application such calculations in cosmology to treat questions structure formation from small-amplitude initial density fluctuations addressed. point process equation discussed, giving general...
view Abstract Citations (1683) References (23) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Excursion Set Mass Functions for Hierarchical Gaussian Fluctuations Bond, J. R. ; Cole, S. Efstathiou, G. Kaiser, N. It is pointed out that most schemes determining the mass function of virialized objects from statistics initial density perturbation field suffer cloud-in-cloud problem miscounting number low-mass clumps, many which would have been subsumed into...
The Simons Observatory (SO) is a new cosmic microwave background experiment being built on Cerro Toco in Chile, due to begin observations the early 2020s. We describe scientific goals of experiment, motivate design, and forecast its performance. SO will measure temperature polarization anisotropy six frequency bands: 27, 39, 93, 145, 225 280 GHz. initial configuration have three small-aperture 0.5-m telescopes (SATs) one large-aperture 6-m telescope (LAT), with total 60,000 cryogenic...
Stochastic inflation can be viewed as a sequence of two-step processes. In the first step stochastic impulse from short-distance quantum fluctuations acts on long waves---the interaction. second waves evolve semiclassically---the propagation. Both steps must developed to address whether for cosmic structure formation may non-Gaussian. We describe formalism following nonlinear propagation long-wavelength metric and scalar-field fluctuations. perform an expansion in spatial gradients...
Scale-invariant (flat) fluctuation spectra are the most natural outcomes of inflation. Nonetheless current large-scale-structure observations seem to indicate more power on large scales than flat give. We consider a wide variety models based chaotic inflation paradigm and sketch effects that varying expansion rate, structure potential surface, curvature coupling constants have quantum spectra. calculate in detail generation by numerically solving linearized perturbation equations for...
view Abstract Citations (793) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Cosmic background radiation anisotropies in universes dominated by nonbaryonic dark matter Bond, J. R. ; Efstathiou, G. Detailed calculations of the temperature fluctuations cosmic for massive collisionless relics big bang are presented. An initially adiabatic constant curvature perturbation spectrum is assumed. In models with cold matter, simplest hypothesis - that...
We present computations of the radiation correlation functions and angular power spectra for microwave background anisotropies expected in Ω = 1 cold dark matter dominated universes with scale-invariant adiabatic or isocurvature initial conditions. The results are valid on all scales. describe statistical properties pattern develop theory two-dimensional Gaussian random fields. A large number such fields may be derived analytically semi-analytically, as densities hotspots coldspots,...
We present new arcminute-resolution maps of the Cosmic Microwave Background temperature and polarization anisotropy from Atacama Cosmology Telescope, using data taken 2013-2016 at 98 150 GHz. The cover more than 17,000 deg$^2$, deepest 600 deg$^2$ with noise levels below 10 $\mu$K-arcmin. use power spectrum derived almost 6,000 these to constrain cosmology. ACT enable a measurement angular scale features in both divergence-like anisotropy, tracing velocity density last-scattering. From one...
We present the science case, reference design, and project plan for Stage-4 ground-based cosmic microwave background experiment CMB-S4.
We develop two methods for estimating the power spectrum, ${C}_{\mathcal{l}},$ of cosmic microwave background from data and apply them to Cosmic Background Explorer Differential Microwave Radiometer Saskatoon datasets. One method involves a direct evaluation likelihood function, other is an estimator that minimum-variance weighted quadratic function data. Applied iteratively, not distinct analysis, but rather rapid means finding spectrum maximizes function. Our results bear this out:...
We present constraints on cosmological and astrophysical parameters from high-resolution microwave background maps at 148 GHz 218 made by the Atacama Cosmology Telescope (ACT) in three seasons of observations 2008 to 2010. A model primary secondary foreground is fit map power spectra lensing deflection spectrum, including contributions both thermal Sunyaev-Zeldovich (tSZ) effect kinematic (kSZ) effect, Poisson correlated anisotropy unresolved infrared sources, radio correlation between tSZ...
view Abstract Citations (358) References (66) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The evolution and fate of Very Massive Objects Bond, J. R. ; Arnett, W. D. Carr, B. structure (stars 100-100,000 solar masses) are discussed in terms simple semianalytic models. helium enrichment due to mass loss is estimated evidence presented for a dynamical instability arising the hydrogen shell burning phase 500 solar-mass Population I star. VMO decided its...
[Abridged] We present a catalog of 68 galaxy clusters, which 19 are new discoveries, detected via the Sunyaev-Zel'dovich effect (SZ) at 148 GHz in Atacama Cosmology Telescope (ACT) survey 504 square degrees on celestial equator. A subsample 48 clusters within 270 degree region overlapping SDSS Stripe 82 is estimated to be 90% complete for M_500c > 4.5e14 Msun and 0.15 < z 0.8. While matched filters used detect sample studied further through "Profile Based Amplitude Analysis" using...
In this paper, we present results from the complete set of cosmic microwave background (CMB) radiation temperature anisotropy observations made with Arcminute Cosmology Bolometer Array Receiver (ACBAR) operating at 150 GHz. We include new data final 2005 observing season, expanding number detector hours by 210% and sky coverage 490% over that used for previous ACBAR release. As a result, band-power uncertainties have been reduced more than factor two on angular scales encompassing third to...
We present cosmological parameters derived from the angular power spectrum of cosmic microwave background (CMB) radiation observed at 148 GHz and 218 over 296 deg2 with Atacama Cosmology Telescope (ACT) during its 2008 season. ACT measures fluctuations scales 500 < ℓ 10, 000. fit a model for lensed CMB, Sunyaev–Zel'dovich (SZ), foreground contribution to spectra, including thermal kinetic SZ, Poisson radio infrared point sources, clustered sources. At = 3000, about half comes primary CMB...
We present the temperature and polarization angular power spectra of CMB measured by Atacama Cosmology Telescope (ACT) from 5400 deg$^2$ 2013-2016 survey, which covers $>$15000 at 98 150 GHz. For this analysis we adopt a blinding strategy to help avoid confirmation bias and, related this, show numerous checks for systematic error done before unblinding. Using likelihood cosmological constrain secondary sources anisotropy foreground emission, derive "CMB-only" spectrum that extends...
Abstract CMB-S4—the next-generation ground-based cosmic microwave background (CMB) experiment—is set to significantly advance the sensitivity of CMB measurements and enhance our understanding origin evolution universe. Among science cases pursued with CMB-S4, quest for detecting primordial gravitational waves is a central driver experimental design. This work details development forecasting framework that includes power-spectrum-based semianalytic projection tool, targeted explicitly toward...
Following the first two annual intensity mapping workshops at Stanford in March 2016 and Johns Hopkins June 2017, we report on recent advances theory, instrumentation observation that were presented these meetings some of opportunities challenges identified looking forward. With preliminary detections CO, [CII], Lya low-redshift 21cm, a host experiments set to go online next few years, field is rapidly progressing all fronts, with great anticipation for flood new exciting results. This...
We present new measurements of cosmic microwave background (CMB) lensing over $9400$ sq. deg. the sky. These are derived from Atacama Cosmology Telescope (ACT) Data Release 6 (DR6) CMB dataset, which consists five seasons ACT temperature and polarization observations. determine amplitude power spectrum at $2.3\%$ precision ($43\sigma$ significance) using a novel pipeline that minimizes sensitivity to foregrounds noise properties. To ensure our results robust, we analyze an extensive set null...
Abstract Ultralight axions and other bosons are dark matter candidates present in many high energy physics theories beyond the Standard Model. In particular, string axiverse postulates existence of up to 𝒪(100) light scalar constituting sector. We test validity effective field theory large-scale structure approach mixed ultralight axion by making our own mock galaxy catalogs find an anisotropic signature quadrupole. use Fourier-space clustering statistics from Baryon Oscillation...