Yossef Zenati
A5054978585- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Neutrino Physics Research
- Solar and Space Plasma Dynamics
- Cardiac Arrest and Resuscitation
- Geomagnetism and Paleomagnetism Studies
- Geophysics and Gravity Measurements
- Galaxies: Formation, Evolution, Phenomena
- Space Satellite Systems and Control
- Influenza Virus Research Studies
- Astrophysics and Star Formation Studies
- Global Trade and Competitiveness
- Culinary Culture and Tourism
- Nuclear physics research studies
- Computational Physics and Python Applications
- Statistical Mechanics and Entropy
- Characterization and Applications of Magnetic Nanoparticles
- Edible Oils Quality and Analysis
- Ionosphere and magnetosphere dynamics
- Dark Matter and Cosmic Phenomena
Johns Hopkins University
2021-2024
Space Telescope Science Institute
2024
Technion – Israel Institute of Technology
2016-2023
Institut Agronomique et Vétérinaire Hassan II
1995
We present panchromatic observations and modeling of supernova (SN) 2020tlf, the first normal type II-P/L SN with confirmed precursor emission, as detected by Young Supernova Experiment transient survey Pan-STARRS1 telescope. Pre-explosion emission was in $riz-$bands at 130 days prior to 2020tlf persisted relatively constant flux until light. Soon after discovery, "flash" spectroscopy revealed prominent narrow symmetric lines ($v_w < 300$ km s$^{-1}$) that resulted from photo-ionization...
Abstract We present UV and/or optical observations and models of SN 2023ixf, a type II supernova (SN) located in Messier 101 at 6.9 Mpc. Early time ( flash ) spectroscopy obtained primarily Lick Observatory, reveals emission lines H i , He i/ii C iv N iii/iv/v with narrow core broad, symmetric wings arising from the photoionization dense, close-in circumstellar material (CSM) around progenitor star prior to shock breakout. These electron-scattering broadened line profiles persist for ∼8 days...
Abstract We present preexplosion optical and infrared (IR) imaging at the site of type II supernova (SN II) 2023ixf in Messier 101 6.9 Mpc. astrometrically registered a ground-based image SN to archival Hubble Space Telescope (HST), Spitzer (Spitzer), near-IR images. A single point source is detected position consistent with wavelengths ranging from HST R band 4.5 μ m. Fitting blackbody red supergiant (RSG) spectral energy distributions (SEDs), we find that anomalously cool significant...
We analyze pre-explosion near- and mid-infrared (IR) imaging of the site SN 2023ixf in nearby spiral galaxy M101 characterize candidate progenitor star. The star displays compelling evidence variability with a possible period $\approx$1000 days an amplitude $\Delta m \approx 0.6$ mag extensive monitoring Spitzer Space Telescope since 2004, likely indicative radial pulsations. Variability consistent this is also seen near-IR $J$ $K_{s}$ bands between 2010 2023, up to just 10 before explosion....
Abstract The JWST Advanced Deep Extragalactic Survey (JADES) is a multicycle program that has taken among the deepest near- and mid-infrared images to date (down ∼30 AB mag) over ∼25 arcmin 2 in GOODS-S field two sets of observations with 1 yr separation. This presented first opportunity systematically search for transients, mostly supernovae (SNe), out z > 2. We found 79 SNe: 38 at < 2, 23 3, 8 3 4, 7 4 5, undetermined redshifts, where redshifts are predominantly based on...
We present multiwavelength observations of the Type II SN 2020pni. Classified at $\sim 1.3$ days after explosion, object showed narrow (FWHM $<250\,\textrm{km}\,\textrm{s}^{-1}$) recombination lines ionized helium, nitrogen, and carbon, as typically seen in flash-spectroscopy events. Using non-LTE radiative transfer code CMFGEN to model our first high resolution spectrum, we infer a progenitor mass-loss rate $\dot{M}=(3.5-5.3)\times10^{-3}$ M$_{\odot}$ yr$^{-1}$ (assuming wind velocity...
We present the Young Supernova Experiment Data Release 1 (YSE DR1), comprised of processed multi-color Pan-STARRS1 (PS1) griz and Zwicky Transient Facility (ZTF) gr photometry 1975 transients with host-galaxy associations, redshifts, spectroscopic/photometric classifications, additional data products from 2019 November 24 to 2021 December 20. YSE DR1 spans discoveries observations young fast-rising supernovae (SNe) that persist for over a year, redshift distribution reaching z~0.5. relative...
We present extensive optical photometry of the afterglow GRB~221009A. Our data cover $0.9 - 59.9$\,days from time \textit{Swift} and \textit{Fermi} GRB detections. Photometry in $rizy$-band filters was collected primarily with Pan-STARRS supplemented by multiple 1- to 4-meter imaging facilities. analyzed Swift X-ray found a single decline rate power-law $f(t) \propto t^{-1.556\pm0.002}$ best describes light curve. In addition high foreground Milky Way dust extinction along this line sight,...
Abstract The nearby type II supernova, SN 2023ixf in M101 exhibits signatures of early time interaction with circumstellar material the first week postexplosion. This may be consequence prior mass loss suffered by progenitor, which possibly manifested form a detectable presupernova outburst. We present an analysis long-baseline preexplosion photometric data g , w r i z and y filters from Pan-STARRS as part Young Supernova Experiment, spanning ∼5000 days. find no significant detections light...
Abstract A bright ( m F150W,AB = 24 mag), z 1.95 supernova (SN) candidate was discovered in JWST/NIRCam imaging acquired on 2023 November 17. The SN is quintuply imaged as a result of strong gravitational lensing by foreground galaxy cluster, detected three locations, and remarkably the second lensed found same host galaxy. previous called “Requiem,” therefore new named “Encore.” This makes MACS J0138.0−2155 cluster first known system to produce more than one multiply SN. Moreover, both...
Abstract We present high-cadence ultraviolet through near-infrared observations of the Type Ia supernova (SN Ia) 2023bee at D = 32 ± 3 Mpc, finding excess flux in first days after explosion, particularly our 10 minutes cadence TESS light curve and Swift UV data. Compared to a few other normal SNe with early flux, SN is redder less luminous. optical spectra 2023bee, including two during period where dominant. At this time, are similar those but weaker Si ii , C ii, Ca absorption lines,...
Abstract In an effort to search for faint sources of emission over arbitrary timescales, we present a novel method analyzing forced photometry light curves in difference imaging from optical surveys. Our “ATLAS Clean,” or ATClean, utilizes the reported fluxes, uncertainties, and fits point-spread function (PSF) images quantify statistical significance individual measurements. We apply this control across image determine whether any source flux is data range specific timescales. From ATLAS o...
A fundamental aspect of the three-body problem is its stability. Most stability studies have focused on co-planar problem, deriving analytic criteria for dynamical such pro/retrograde systems. Numerical inclined systems phenomenologically mapped their regions, but neither complement it by theoretical framework, nor provided satisfactory fit dependence mutual inclinations. Here we present a novel approach to study hierarchical at arbitrary inclinations, which accounts not only instantaneous...
White dwarfs (WDs) are the stellar core remnants of low mass (|${\lesssim }8\, {\rm M_{\odot }})$| stars. They typically divided into three main composition groups: oxygen–neon (ONe), carbon–oxygen (CO), and helium (He) WDs. The evolution binary systems can significantly change components. In particular, striping envelope an evolved star give rise to a remnant, which later evolve WD with different composition. Here we focus on formation hybrid HeCO We follow such WDs for range initial...
Abstract We present panchromatic observations and modeling of the Calcium-rich supernova (SN) 2019ehk in star-forming galaxy M100 ( d ≈ 16.2 Mpc) starting 10 hr after explosion continuing for ∼300 days. SN shows a double-peaked optical light curve peaking at t = 3 15 The first peak is coincident with luminous, rapidly decaying Swift-XRT–discovered X-ray emission <?CDATA ${L}_{{\rm{x}}}\approx {10}^{41}\,\mathrm{erg}\,{{\rm{s}}}^{-1}$?> days; L x ∝ −3 ), Shane/Kast spectral detection narrow H...
The mergers of neutron stars (NSs) and white dwarfs (WDs) could give rise to explosive transients, potentially observable with current future transient surveys. However, the expected properties distribution such events is not well understood. Here we characterize rates events, their delay time distribution, progenitors properties. We use binary populations synthesis models consider a wide range initial conditions physical processes. In particular different common-envelope evolution NS natal...
ABSTRACT Normal type Ia supernovae (SNe) are thought to arise from the thermonuclear explosion of massive (&gt;0.8 M⊙) carbon–oxygen white dwarfs (WDs), although exact mechanism is debated. In some models, helium accretion on a (CO) WD companion was suggested dynamically trigger detonation accreted shell. The then produces shock that after converging itself close core CO WD, triggers secondary carbon detonation, and gives rise an energetic explosion. However, most studies such scenarios...
Abstract We present photometric and spectroscopic observations of Supernova 2020oi (SN 2020oi), a nearby (∼17 Mpc) type-Ic supernova Ic) within the grand-design spiral M100. undertake comprehensive analysis to characterize evolution SN constrain its progenitor system. detect flux in excess fireball rise model δ t ≈ 2.5 days from date explosion multiband optical UV photometry Las Cumbres Observatory Neil Gehrels Swift Observatory, respectively. The derived bolometric luminosity is consistent...
Abstract Calcium-rich explosions are very faint ( M B ∼ −15.5), type I supernovae (SNe) showing strong Ca lines, mostly observed in old stellar environments. Several models for such SNe have been explored and debated, but none were able to reproduce consistently the properties of Ca-rich SNe, nor their rates host-galaxy distributions. Here we show that disruptions low-mass carbon–oxygen (CO) white dwarfs (WDs) by hybrid helium–CO (HeCO) WDs during merger could explain origin SNe. We make use...
Supernovae (SNe) that have been multiply-imaged by gravitational lensing are rare and powerful probes for cosmology. Each detection is an opportunity to develop the critical tools methodologies needed as sample of lensed SNe increases orders magnitude with upcoming Vera C. Rubin Observatory Nancy Grace Roman Space Telescope. The latest such discovery quadruply-imaged Type Ia SN 2022qmx (aka, "SN Zwicky") at $z=0.3544$. Zwicky was discovered Transient Facility (ZTF) in spatially unresolved...
Neutron-star (NS) - white-dwarf (WD) mergers may give rise to observable explosive transients, but have been little explored. We use 2D coupled hydrodynamical-thermonuclear FLASH-code simulations study the evolution of WD debris-disks formed following WD-disruptions by NSs. a 19-elements nuclear-network and detailed equation-of-state follow evolution, complemented post-process analysis using larger 125-isotopes nuclear-network. consider wide range initial conditions dependence results on...
ABSTRACT We conduct the first 3D hydrodynamic simulations of oxygen–neon white dwarf–neutron star/black hole mergers (ONe WD–NS/BH mergers). Such constitute a significant fraction, and may even dominate, inspiral rates all WD–NS binaries. post-process our to obtain nuclear evolution these systems couple results supernova spectral synthesis code light curves spectra for transients. find that amount 56Ni synthesized in grows as strong function WD mass, reaching typically 0.05 up $0.1\, {\rm...
We present panchromatic observations and modeling of calcium-strong supernovae (SNe) 2021gno in the star-forming host galaxy NGC 4165 (D = 30.5 Mpc) 2021inl outskirts elliptical 4923 80 Mpc), both monitored through Young Supernova Experiment (YSE) transient survey. The multi-color light curves SNe show two peaks, former peak being derived from shock cooling emission (SCE) and/or interaction with circumstellar material (CSM). primary SN is coincident luminous, rapidly decaying X-ray ($L_x 5...
We present optical and near-infrared (NIR) observations of the Type Icn supernova (SN Icn) 2022ann, fifth member its newly identified class SNe. Its early spectra are dominated by narrow carbon oxygen P-Cygni features with absorption velocities 800 km/s; slower than other SNe indicative interaction a dense, H/He-poor circumstellar medium (CSM) that is outflowing typical Wolf-Rayet wind velocity $>$1000 km/s. identify helium in NIR obtained two weeks after maximum at three weeks,...