E. O. Ofek
A5078910984- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Galaxies: Formation, Evolution, Phenomena
- SAS software applications and methods
- Adaptive optics and wavefront sensing
- Astrophysics and Star Formation Studies
- Solar and Space Plasma Dynamics
- Calibration and Measurement Techniques
- Neutrino Physics Research
- Radio Astronomy Observations and Technology
- Geophysics and Gravity Measurements
- CCD and CMOS Imaging Sensors
- Particle Accelerators and Free-Electron Lasers
- Planetary Science and Exploration
- Spacecraft and Cryogenic Technologies
- Advanced Graph Theory Research
- Isotope Analysis in Ecology
- Limits and Structures in Graph Theory
- Nuclear Physics and Applications
Weizmann Institute of Science
2015-2024
Google (United States)
2020-2022
California Institute of Technology
2006-2020
Australian National University
2020
Kavli Institute for Particle Astrophysics and Cosmology
2016
SLAC National Accelerator Laboratory
2016
Pennsylvania State University
2016
Max Planck Institute for Radio Astronomy
2015
Max Planck Society
2015
Tel Aviv University
1996-2013
The Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched on 2012 June 13, is the first focusing high-energy X-ray telescope in orbit. NuSTAR operates band from 3 to 79 keV, extending sensitivity of far beyond ∼10 keV cutoff achieved by all previous satellites. inherently low background associated with concentrating light enables probe hard sky a more than 100-fold improvement over collimated or coded mask instruments that have operated this bandpass. Using its unprecedented...
The Palomar Transient Factory (PTF) is a fully-automated, wide-field survey aimed at systematic exploration of the optical transient sky. performed using new 8.1 square degree camera installed on 48-inch Samuel Oschin telescope Observatory; colors and light curves for detected transients are obtained with automated 60-inch telescope. PTF uses eighty percent 1.2-m fifty 1.5-m time. With an exposure 60-s reaches depth approximately 21.3 in g' 20.6 R (5 sigma, median seeing). Four major...
The Palomar Transient Factory (PTF) is a wide-field experiment designed to investigate the optical transient and variable sky on time scales from minutes years. PTF uses CFH12k mosaic camera, with field of view 7.9 deg2 plate scale 1'' pixel-1, mounted Observatory 48 inch Samuel Oschin Telescope. operation strategy devised probe existing gaps in phase space search for theoretically predicted, but not yet detected, phenomena, such as fallback supernovae, macronovae,. Ia orphan afterglows...
The Zwicky Transient Facility (ZTF), a public-private enterprise, is new time domain survey employing dedicated camera on the Palomar 48-inch Schmidt telescope with 47 deg$^2$ field of view and 8 second readout time. It well positioned in development astronomy, offering operations at 10% scale style Large Synoptic Survey Telescope (LSST) single 1-m class telescope. public surveys will cover observable northern sky every three nights g r filters visible Galactic plane night r. Alerts...
Merging neutron stars offer an exquisite laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of electromagnetic counterpart EM170817 to gravitational waves (GW170817) detected from merging stars. By synthesizing a panchromatic dataset, we demonstrate that are long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma-rays seen dissimilar classical short gamma-ray bursts with...
We present the results of a Palomar Transient Factory (PTF) archival search for blue transients which lie in magnitude range between "normal" core-collapse and superluminous supernovae (i.e. with $-21\,{\leq}M_{R\,(peak)}\,{\leq}-19$). Of six events found after excluding all interacting Type~IIn Ia-CSM supernovae, three (PTF09ge, 09axc 09djl) are coincident centers their hosts, one (10iam) is offset from center, two (10nuj 11glr) precise can not be determined. All central have similar rise...
We report the discovery by Swift hard X-ray monitor of transient source J2058.4+0516 (Sw J2058+05). Our multi-wavelength follow-up campaign uncovered a long-lived (duration ≳ months), luminous (LX, iso ≈ 3 × 1047 erg s−1) and radio (νLν, 1042 counterpart. The associated optical emission, however, from which we measure redshift 1.1853, is relatively faint, this not due to large amount dust extinction in host galaxy. Based on numerous similarities with recently discovered GRB 110328A/Swift...
We present the first measurement of planet frequency beyond "snow line," for planet-to-star mass-ratio interval −4.5 < log q −2, corresponding to range ice giants gas giants. find at mean mass ratio = 5 × 10−4 with no discernible deviation from a flat (Öpik's law) distribution in log-projected separation s. The determination is based on sample six planets detected intensive follow-up observations high-magnification (A>200) microlensing events during 2005–2008. sampled host stars have typical...
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....
Stellar Explosions Stars that are born with masses greater than eight times of the Sun end their lives in luminous explosions known as supernovae. Over past decade, access to improved sky surveys has revealed rare types supernovae much more any those were before. Gal-Yam (p. 927 ) reviews these superluminous events and groups them into three classes share common observational physical characteristics. Gamma-ray bursts another type extreme explosive related death massive stars, which occur...
Fast radio bursts (FRBs) are one of the most tantalizing mysteries sky; their progenitors and origins remain unknown until now no rapid multiwavelength follow-up an FRB has been possible. New instrumentation decreased time between observation discovery from years to seconds, enables polarimetry be performed on FRBs for first time. We have discovered (FRB 140514) in real-time 14 May, 2014 at 17:14:11.06 UTC Parkes telescope triggered other wavelengths within hours event. 140514 was found with...
We present a novel algorithm for scheduling the observations of time-domain imaging surveys. Our Integer Linear Programming approach optimizes an observing plan entire night by assigning targets to temporal blocks, enabling strict control number exposures obtained per field and minimizing filter changes. A subsequent optimization step minimizes slew times between each observation. metric self-consistently weights contributions from time-varying airmass, seeing, sky brightness maximize...
The Zwicky Transient Facility (ZTF) is a new robotic time-domain survey currently in progress using the Palomar 48-inch Schmidt Telescope. ZTF uses 47 square degree field with 600 megapixel camera to scan entire northern visible sky at rates of ~3760 degrees/hour median depths g ~ 20.8 and r 20.6 mag (AB, 5sigma 30 sec). We describe Science Data System that housed IPAC, Caltech. This comprises data-processing pipelines, alert production system, data archive, user interfaces for accessing...
ABSTRACT Transient detection and flux measurement via image subtraction stand at the base of time domain astronomy. Due to varying seeing conditions, process is non-trivial, existing solutions suffer from a variety problems. Starting basic statistical principles, we develop optimal statistic for transient detection, measurement, any image-difference hypothesis testing. We derive closed-form that: (1) mathematically proven be in limit background-dominated noise, (2) numerically stable, (3)...