A. S. Fruchter
A5055371146- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- SAS software applications and methods
- Astronomical Observations and Instrumentation
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Galaxies: Formation, Evolution, Phenomena
- Geophysics and Gravity Measurements
- Adaptive optics and wavefront sensing
- CCD and CMOS Imaging Sensors
- Radio Astronomy Observations and Technology
- Cosmology and Gravitation Theories
- Superconducting Materials and Applications
- High-pressure geophysics and materials
- Solar and Space Plasma Dynamics
- History and Developments in Astronomy
- Particle Detector Development and Performance
- Particle Accelerators and Free-Electron Lasers
- Calibration and Measurement Techniques
- Astrophysics and Star Formation Studies
- Scientific Research and Discoveries
- Advanced X-ray and CT Imaging
Space Telescope Science Institute
2015-2024
AlbaNova
2021
George Washington University
2021
KTH Royal Institute of Technology
2021
Michigan Science Center
1993-2019
Johns Hopkins University
2009-2010
University of Hawaii System
2009
University of Baltimore
2009
University of Leicester
2009
University of Warwick
2009
We report measurements of the mass density, ΩM, and cosmological-constant energy ΩΛ, universe based on analysis 42 type Ia supernovae discovered by Supernova Cosmology Project. The magnitude-redshift data for these supernovae, at redshifts between 0.18 0.83, are fitted jointly with a set from Calán/Tololo Survey, below 0.1, to yield values cosmological parameters. All supernova peak magnitudes standardized using SN light-curve width-luminosity relation. measurement yields joint probability...
The Swift mission, scheduled for launch in 2004, is a multiwavelength observatory gamma-ray burst (GRB) astronomy. It first-of-its-kind autonomous rapid-slewing satellite transient astronomy and pioneers the way future rapid-reaction missions. will be far more powerful than any previous GRB observing 100 bursts yr-1 performing detailed X-ray UV/optical afterglow observations spanning timescales from 1 minute to several days after burst. objectives are (1) determine origin of GRBs, (2)...
The Lyman decrement associated with the cumulative effect of HI in QSO absorption systems along line sight provides a distinctive feature for identifying galaxies at z>2.5. Hubble Deep Field (HDF) observations offer opportunity to exploit ubiquitous intergalactic and obtain useful statistical constraints on redshift distribution considerably fainter than current spectroscopic limits. We model cosmic opacity as function redshift, including scattering resonant lines series Lyman-continuum...
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 report measurements of ΩM, ΩΛ, and w from 11 supernovae (SNe) at z = 0.36-0.86 with high-quality light curves measured using WFPC2 on the Hubble Space Telescope (HST). This is an independent set high-redshift SNe that confirms previous SN evidence for accelerating universe. The available photometry make it possible these alone to provide cosmological parameters comparable in statistical weight results. Combined earlier Supernova Cosmology Project data, new yield a measurement mass density...
This special issue of the Astrophysical Journal Letters is dedicated to presenting initial results from Great Observatories Origins Deep Survey (GOODS) that are primarily, but not exclusively, based on multiband imaging data obtained with Hubble Space Telescope and Advanced Camera for Surveys (ACS). The survey covers roughly 320 arcmin2 in ACS F435W, F606W, F814W, F850LP bands, divided into two well-studied fields. Existing deep observations Chandra X-Ray Observatory ground-based facilities...
The Hubble Deep Field (HDF) is a Director's Discretionary program on HST in Cycle 5 to image an undistinguished field at high Galactic latitude four passbands as deeply reasonably possible. These images provide the most detailed view date of distant galaxies and are likely be important for wide range studies galaxy evolution cosmology. In order optimize observing time available, northern continuous viewing zone was selected were taken ten consecutive days, or approximately 150 orbits....
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...
Abstract We report the discovery and monitoring of near-infrared counterpart (AT2017gfo) a binary neutron-star merger event detected as gravitational wave source by Advanced Laser Interferometer Gravitational-wave Observatory (LIGO)/Virgo (GW170817) short gamma-ray burst Fermi Gamma-ray Burst Monitor (GBM) Integral SPI-ACS (GRB 170817A). The evolution transient light is consistent with predictions for behavior “kilonova/macronova” powered radioactive decay massive neutron-rich nuclides...
We have developed a method for the linear reconstruction of an image from undersampled, dithered data. The algorithm, known as Variable-Pixel Linear Reconstruction, or informally Drizzle, preserves photometry and resolution, can weight input images according to statistical significance each pixel, removes effects geometric distortion both on shape photometry. This paper presents its implementation. photometric astrometric accuracy fidelity algorithm well noise characteristics output are...
While gas accretion onto some massive black holes (MBHs) at the centers of galaxies actively powers luminous emission, vast majority MBHs are considered dormant. Occasionally, a star passing too near MBH is torn apart by gravitational forces, leading to bright panchromatic tidal disruption flare (TDF). high-energy transient Swift J164449.3+573451 ("Sw 1644+57") initially displayed none theoretically anticipated (nor previously observed) TDF characteristics, we show that observations (Levan...
Gamma-ray bursts (GRBs) serve as powerful probes of the early Universe, with their luminous afterglows revealing locations and physical properties star forming galaxies at highest redshifts, potentially locating first generation (Population III) stars. Since GRB have intrinsically very simple spectra, they allow robust redshifts from low signal to noise spectroscopy, or photometry. Here we present a photometric redshift z~9.4 for Swift-detected 090429B based on deep observations...
Variable X-ray and gamma-ray emission is characteristic of the most extreme physical processes in Universe, studying sources these energetic photons has been a major driver astronomy for past 50 years. Here we present multiwavelength observations unique selected transient, discovered by Swift, which was accompanied bright across electromagnetic spectrum, whose properties are unlike any previously observed source. We pinpoint event to center small, star-forming galaxy at redshift z=0.3534....
(Abridged). We present a sample of 77 optical afterglows (OAs) Swift detected GRBs for which spectroscopic follow-up observations have been secured. provide linelists and equivalent widths all lines redward Ly-alpha. discuss to what extent the current bursts with OA spectroscopy is biased subsample GRBs. For that purpose we define an X-ray selected optimal conditions ground-based follow up from period March 2005 September 2008; 146 fulfill our criteria. derive redshift distribution this...