A5082665258- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Galaxies: Formation, Evolution, Phenomena
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- CCD and CMOS Imaging Sensors
- Radio Astronomy Observations and Technology
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- Statistical and numerical algorithms
- History and Developments in Astronomy
- Particle physics theoretical and experimental studies
- Big Data Technologies and Applications
- Pulsars and Gravitational Waves Research
- Gaussian Processes and Bayesian Inference
- Advanced Image Processing Techniques
- Distributed and Parallel Computing Systems
- Geophysics and Sensor Technology
- Medical Imaging and Analysis
- GNSS positioning and interference
Kavli Institute for Particle Astrophysics and Cosmology
2014-2024
Stanford University
2013-2024
SLAC National Accelerator Laboratory
2023-2024
Lawrence Livermore National Laboratory
2019-2023
Vera C. Rubin Observatory
2023
Conexant (United States)
2022
Princeton University
2017-2019
University at Buffalo, State University of New York
2018-2019
Kaleida Health
2018-2019
Buffalo General Medical Center
2018-2019
We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe were discovered over redshift interval 0.623 < z 1.415. Of these Ia, 14 pass our strict selection cuts are used in combination with world's sample to derive best current constraints on dark energy. new 10 beyond = 1, thereby nearly doubling statistical weight HST-discovered this redshift. Our...
We present a new compilation of Type Ia supernovae (SNe Ia), dataset low-redshift nearby-Hubble-flow SNe and analysis procedures to work with these heterogeneous compilations. This ``Union'' 414 SN Ia, which reduces 307 after selection cuts, includes the recent large samples from Supernova Legacy Survey ESSENCE Survey, older datasets, as well recently extended distant observed HST. A single, consistent blind procedure is used for all various subsamples, implemented that consistently weights...
We report on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts. Light curves, including signal-to-noise Hubble Space Telescope data, and spectra six SNe that were discovered during 2001, are presented. Additionally, for two with z > 1, we present ground-based J-band photometry from Gemini Very Large Telescope. These among most distant which near-IR observations have been obtained. add these together other data sets recently become available in...
We have identified 335 galaxy cluster and group candidates, 106 of which are at z > 1, using a 4.5 um selected sample objects from 7.25 deg^2 region in the Spitzer Infrared Array Camera (IRAC) Shallow Survey. Clusters were as 3-dimensional overdensities wavelet algorithm, based on photometric redshift probability distributions derived IRAC NOAO Deep Wide-Field Survey data. estimate only ~10% detections spurious. To date 12 1 candidates been confirmed spectroscopically, redshifts 1.06 to...
We present new limits on ultrahigh energy neutrino fluxes above ${10}^{17}\text{ }\text{ }\mathrm{eV}$ based data collected by the Radio Ice Cherenkov Experiment (RICE) at South Pole from 1999--2005. discuss estimation of backgrounds, calibration and analysis algorithms (both online offline), procedures used for dedicated search, refinements in our Monte Carlo (MC) simulation, including recent situ measurements complex ice dielectric constant. An enlarged set a more detailed study hadronic...
We present first results from the third GRavitational lEnsing Accuracy Testing (GREAT3) challenge, in a sequence of challenges for testing methods inferring weak gravitational lensing shear distortions simulated galaxy images. GREAT3 was divided into experiments to test three specific questions, and included space- ground-based data with constant or cosmologically varying fields. The simplest (control) experiment parametric galaxies realistic distribution signal-to-noise, size, ellipticity,...
We present results from a set of simulations designed to constrain the weak lensing shear calibration for Hyper Suprime-Cam (HSC) survey. These include HSC observing conditions and galaxy images Hubble Space Telescope (HST), with fully realistic morphologies impact nearby galaxies included. find that inclusion in is critical reproducing observed distributions sizes magnitudes, due non-negligible fraction unrecognized blends ground-based data, even excellent typical seeing survey (0.58"...
The Large Synoptic Survey Telescope (LSST) Dark Energy Science Collaboration (DESC) will use five cosmological probes: galaxy clusters, large scale structure, supernovae, strong lensing, and weak lensing. This Requirements Document (SRD) quantifies the expected dark energy constraining power of these probes individually together, with conservative assumptions about analysis methodology follow-up observational resources based on our current understanding evolution within field in coming...
Abstract We describe the simulated sky survey underlying second data challenge (DC2) carried out in preparation for analysis of Vera C. Rubin Observatory Legacy Survey Space and Time (LSST) by LSST Dark Energy Science Collaboration (LSST DESC). Significant connections across multiple science domains will be a hallmark LSST; DC2 program represents unique modeling effort that stresses this interconnectivity way has not been attempted before. This encompasses full end-to-end approach: starting...
We present weak gravitational lensing analysis of 22 high-redshift (z >~1) clusters based on Hubble Space Telescope images. Most in our sample provide significant signals and are well detected their reconstructed two-dimensional mass maps. Combining the current results previous weak-lensing studies five other high-z clusters, we compare masses these with observables. revisit question whether presence most massive is tension LambdaCDM structure formation paradigm. find that tightly correlated...
Recent independent results from numerical simulations and observations have shown that brightest cluster galaxies (BCGs) increased their stellar mass by a factor of almost two between z~0.9 z~0.2. The further suggest more than half this is accreted through major mergers. Using sample 18 distant galaxy clusters with over 600 spectroscopically confirmed members them, we search for observational evidence mergers do play significant role. We find merger rate 0.38 +/- 0.14 per Gyr at z~1. While...
We present observations of SCP 06F6, an unusual optical transient discovered during the Hubble Space Telescope Cluster Supernova Survey. The brightened over a period ~100 days, reached peak magnitude ~21.0 in both i_775 and z_850, then declined similar timescale. There is no host galaxy or progenitor star detected at location to 3 sigma upper limit = 26.4 z_850 26.1, giving corresponding lower on flux increase factor ~120. Multiple spectra show five broad absorption bands between 4100 AA...
ABSTRACT We present and validate 20 deg2 of overlapping synthetic imaging surveys representing the full depth Nancy Grace Roman Space Telescope High-Latitude Imaging Survey (HLIS) 5 yr observations Vera C. Rubin Observatory Legacy Time (LSST). The two are summarized, with reference to existing 300 LSST simulated produced as part Dark Energy Science Collaboration (DESC) Data Challenge 2 (DC2). Both observe same DESC DC2 universe. For survey, we simulate for first time fully chromatic images...
The OpenUniverse2024 simulation suite is a cross-collaboration effort to produce matched simulated imaging for multiple surveys as they would observe common sky. Both the data and associated tools used it are intended uniquely enable wide range of studies maximize science potential next generation cosmological surveys. We have produced approximately 70 deg$^2$ Vera C. Rubin Observatory Legacy Survey Space Time (LSST) Wide-Fast-Deep survey Nancy Grace Roman Telescope High-Latitude Wide-Area...
We present a study of the morphological fractions and color–magnitude relation (CMR) in most distant X-ray selected galaxy cluster currently known, XMMXCS J2215.9 − 1738 at z = 1.46, using combination optical imaging data obtained with Hubble Space Telescope Advanced Camera for Surveys, infrared from Multi-Object Infrared Spectrograph, mounted on 8.2 m Subaru telescope. find that mix population is similar to clusters ∼ 1. Within central 0.5 Mpc, approximately ∼62% galaxies identified as...
We present a new survey strategy to discover and study high-redshift Type Ia supernovae (SNe Ia) using the Hubble Space Telescope (HST). By targeting massive galaxy clusters at 0.9 < z 1.5, we obtain twofold improvement in efficiency of finding SNe compared an HST field factor 3 total yield SN detections relatively dust-free red-sequence galaxies. In total, sixteen were discovered z>0.95, nine which clusters. This provides sample that can be used decouple effects host-galaxy extinction...
We present a new measurement of the volumetric rate SNe Ia up to redshift 1.7, using HST GOODS data combined with an additional set covering GOODS-North field collected in 2004. employ novel technique that does not require spectroscopic for identifying (although measurements redshifts are used over half sample); instead, we Bayesian approach only photometric calculate probability object is SN Ia. This can easily be modified incorporate improved priors on properties, and it well-suited future...
We report the discovery of a redshift 1.71 supernova in GOODS North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from host or neighboring galaxies. Although rest frame sampled range is too blue to include any Si ii line, principal component analysis allows us confirm it as Type Ia with 92% confidence. A recent serendipitous archival HST WFC3 grism contributed key element confirmation by giving host-galaxy 1.713 +/- 0.007. In addition being most...
We report a measurement of the Type Ia supernova (SN Ia) rate in galaxy clusters at 0.9 < z 1.46 from Hubble Space Telescope Cluster Supernova Survey. This is first cluster SN with detected > SNe. Finding 8 ± 1 SNe Ia, we determine an 0.50+0.23−0.19 (stat) +0.10−0.09 (sys) h270 SNuB (SNuB ≡ 10−12 L−1☉, B yr−1). In units stellar mass, this translates to 0.36+0.16−0.13 +0.07−0.06 SNuM (SNuM M−1☉ represents factor ≈5 2 increase over measurements 0.2. parameterize late-time delay time...
Using three magnified Type Ia supernovae (SNe Ia) detected behind CLASH (Cluster Lensing and Supernovae with Hubble) clusters, we perform a first pilot study to see whether standardizable candles can be used calibrate cluster mass maps created from strong lensing observations. Such calibrations will crucial when next-generation Hubble Space Telescope surveys (e.g. Frontier) provide magnification that will, in turn, form the basis for exploration of high-redshift Universe. We classify SNe...
The recent robust and homogeneous analysis of the world's supernova distance–redshift data, together with cosmic microwave background baryon acoustic oscillation data—provides a powerful tool for constraining cosmological models. Here we examine particular classes scalar field, modified gravity, phenomenological models to assess whether they are consistent observations even when their behavior deviates from constant Λ. Some have tension while others survive only by approaching constant,...
Using the sample of Type Ia supernovae (SNe Ia) discovered by Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe in GOODS fields, we search for correlations between properties their host galaxies at high redshift. We use galaxy color quantitative morphology to determine red sequence 25 clusters develop a model distinguish passively evolving early-type from star-forming both field. With this approach, identify six SN hosts that are cluster members eleven...