A5032635877- Atomic and Molecular Physics
- Laser-induced spectroscopy and plasma
- X-ray Spectroscopy and Fluorescence Analysis
- Mass Spectrometry Techniques and Applications
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Advanced Chemical Physics Studies
- Adaptive optics and wavefront sensing
- Non-Destructive Testing Techniques
- Ion-surface interactions and analysis
- Stellar, planetary, and galactic studies
- Nuclear physics research studies
- Electron and X-Ray Spectroscopy Techniques
- Astrophysical Phenomena and Observations
- Astronomical Observations and Instrumentation
- Photocathodes and Microchannel Plates
- Superconducting Materials and Applications
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Advanced Power Generation Technologies
- Spectroscopy and Laser Applications
- Optical Systems and Laser Technology
- Astro and Planetary Science
- Electrical Fault Detection and Protection
- Cold Atom Physics and Bose-Einstein Condensates
Weizmann Institute of Science
2017-2024
National Institute for Astrophysics
2020-2022
Astronomical Observatory of Rome
2020-2022
Millennium Institute of Astrophysics
2020
Universidad Andrés Bello
2020
University of Turku
2020
Brera Astronomical Observatory
2020
Osservatorio Astronomico di Cagliari
2020
American Committee for the Weizmann Institute of Science
2020
Hebrew University of Jerusalem
2015
Abstract We present a public catalog of transients from the Zwicky Transient Facility (ZTF) Bright Survey, magnitude-limited ( m < 19 mag in either g or r filter) survey for extragalactic ZTF stream. introduce cuts on coverage, sky visibility around peak light, and other properties unconnected to nature transient, show that resulting statistical sample is spectroscopically 97% complete at <18 mag, 93% <18.5 75% <19 mag. summarize fundamental this population, identifying distinct...
Abstract We present a search for extragalactic fast blue optical transients (FBOTs) during Phase I of the Zwicky Transient Facility (ZTF). identify 38 candidates with durations above half-maximum light 1 day < t 1/2 12 days, which 28 have ( g − r ≲ −0.2 mag) colors at peak light. Of (28 FBOTs), 19 (13) can be spectroscopically classified as core-collapse supernovae (SNe): 11 (8) H- or He-rich (Type II/IIb/Ib) SNe, 6 (4) interacting IIn/Ibn) and 2 (1) H&He-poor Ic/Ic-BL) SNe. Two FBOTs...
Abstract Narrow transient emission lines (flash-ionization features) in early supernova (SN) spectra trace the presence of circumstellar material (CSM) around massive progenitor stars core-collapse SNe. The disappear within days after SN explosion, suggesting that this is spatially confined, and originates from enhanced mass loss shortly (months to a few years) prior explosion. We performed systematic survey H-rich (Type II) SNe discovered less than 2 explosion during first phase Zwicky...
The ejected-electron spectra of highly excited autoionising levels Li, Be, B and C have been studied by using the projectile electron spectroscopy method. Singly doubly core-excited states are strongly populated in 100 to 500 keV Li+, Be+, B+ C+ single collisions with He CH4. High resolution is obtained selecting a small observation angle (6.4 degrees ) respect beam axis. Numerous states, previously not seen, resolved identified comparison existing theoretical data. For large number absolute...
Abstract The Large Array Survey Telescope (LAST) is a wide-field visible-light telescope array designed to explore the variable and transient sky with high cadence. LAST will be composed of 48, 28 cm f/2.2 telescopes (32 already installed) equipped full-frame backside-illuminated cooled CMOS detectors. Each provides field view (FoV) 7.4 deg 2 1.″25 pix −1 , while system FoV 355 in 2.9 Gpix. total collecting area LAST, 48 telescopes, equivalent 1.9 m telescope. cost-effectiveness (i.e.,...
We have used the beam-foil interaction mechanism to populate highly excited states in lithium by passing 300-keV ${\mathrm{Li}}^{+}$ ions through 8-\ensuremath{\mu}g/${\mathrm{cm}}^{2}$-thick carbon foils. The energies of electrons emitted via autoionization were analyzed. By moving foil along beam axis, prompt and delayed due decays Lii Liii identified. These spectra are interpreted with help detailed theoretical calculations. excitation $\mathrm{LiI}(1s2{s}^{2})^{2}S^{e}$...
The electron spectra of autoionizing states Li I and II were studied using H+ He+ bombardment. Excitation energies core-excited levels in measured, some them to within +or-10 meV accuracy. For the metastable state (1s2s2p)4P0 an excitation energy 57.385 eV was obtained.
Among the supernovae (SNe) that show strong interaction with circumstellar medium, there is a rare subclass of Type Ia supernovae, SNe Ia-CSM, narrow hydrogen emission lines much like IIn but on top diluted over-luminous spectrum. In only previous systematic study this class (Silverman et al. 2013), 16 objects were identified, 8 historic and from Palomar Transient Factory (PTF). Now using successor survey to PTF, Zwicky Facility (ZTF), we have classified 12 additional type through Bright...
Abstract We present the discovery and analysis of SN 2022oqm, a Type Ic supernova (SN) detected <1 day after explosion. The rises to blue short-lived (2 days) initial peak. Early-time spectral observations 2022oqm show hot (40,000 K) continuum with high ionization C O absorption features at velocities 4000 km s −1 , while its photospheric radius expands 20,000 indicating pre-existing distribution expanding C/O material. After ∼2.5 days, both spectrum light curves evolve into those typical...
Abstract Luminous red novae (LRNe) are transients characterized by low luminosities and expansion velocities, they associated with mergers or common-envelope ejections in stellar binaries. Intermediate-luminosity (ILRTs) an observationally similar class unknown origins, but generally believed to be either electron-capture supernovae super-asymptotic giant branch stars outbursts dusty luminous blue variables (LBVs). In this paper, we present a systematic sample of eight LRNe ILRTs detected as...
Obtaining spectroscopic observations of the progenitors core-collapse supernovae is often unfeasible, due to an inherent lack knowledge as what stars experience and when they will explode. In this Letter we present photometric progenitor activity SN 2023fyq before He-rich explodes a Type Ibn supernova. The shows exponential rise in flux prior core collapse. Complex He I emission line features are observed spectra, with P Cygni-like profile, well evolving broad base velocities order 10 000 km...
Abstract We present a sample of 34 normal Type II supernovae (SNe II) detected with the Zwicky Transient Facility, multiband UV light curves starting at t ≤ 4 days after explosion, and X-ray observations. characterize early UV-optical color, provide empirical host-extinction corrections, show that > 2 day colors blackbody evolution are consistent shock cooling (SC) regardless presence “flash ionization” features. framework for fitting SC models can reproduce parameters set multigroup...
High-resolution projectile Auger spectra of singly and doubly core-excited oxygen ions are studied as a function incident beam energy (2-18 MeV), exciter gas (helium, neon, argon, krypton) or foil (carbon), charge state (1+ to 4+), delay time. Auger-electron production from excited states varies considerably for collisions with different energies gases. A striking similarity in both the linewidths relative line intensities is observed single-collision multiplecollision excitation. The ion...
As a student, James Clerk Maxwell invented hypothetical optical device, $M\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}x\phantom{\rule{0}{0ex}}w\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}{l}^{\ensuremath{'}}\phantom{\rule{0}{0ex}}s$ $f\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}s\phantom{\rule{0}{0ex}}h\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}y\phantom{\rule{0}{0ex}}e$ (MFE), in which light goes circles and every point is focused. 164 years later,...
Obtaining spectroscopic observations of the progenitors core-collapse supernovae is often unfeasible due to an inherent lack knowledge as which stars will go supernova and when they explode. In this letter, we present photometric progenitor activity SN 2023fyq in preceding 150 days before He-rich exploded a Type Ibn supernova. The shows exponential rise flux prior core-collapse. Complex He I emission line features are observed, with P-Cygni like profile, well evolving broad base velocities...
By using saddle-point technique, 12 autoionizing and two metastable states of B III are calculated. To obtain high accuracy relativistic effects mass polarization effect included in the computation. Spin-orbit, spin---other-orbit, spin-spin also considered. Using IV $(1{s}^{2})^{1}S$ result Pekeris corresponding Auger energies tabulated. These data then used to recalibrate reported boron electron spectra R\o{}dbro, Bruch, Bisgaard by about 0.15 eV. The calculated enable us make seven new...
K -shell binding energies in free atoms for Be, B, and C have been obtained to within a few tenths of an eV by applying Auger spectroscopy fast ion beams being core-excited single collisions with CH 4 He. The present values, which correspond the lowest possible ionization energy, i.e., B E 1 S = (1 s 2 p ) 3 P 0 - , are considerably higher than previous values derived from measurements where solid or molecular samples used, while good agreement is found recent free-atom theoretical data.
We have measured high-resolution electron decay-in-flight spectra of highly excited carbon ions, produced by 2-MeV ${\mathrm{C}}^{+}$ beams emerging from foils. An almost complete identification for the resolved spectral lines is suggested prompt and time-delayed emission spectra. To assign observed structures excitation energies various core-excited states been calculated using generalized Brillouin theorem-multiconfiguration method Schwarz Chang. Experimental term Coulomb metastable...
Abstract High-cadence transient surveys are able to capture supernovae closer their first light than ever before. Applying analytical models such early emission, we can constrain the progenitor stars’ properties. In this paper, present observations of SN 2018fif (ZTF 18abokyfk). The supernova was discovered close and monitored by Zwicky Transient Facility (ZTF) Neil Gehrels Swift Observatory. Early spectroscopic suggest that surrounded relatively small amounts circumstellar material compared...
We present a search for extragalactic fast blue optical transients (FBOTs) during Phase I of the Zwicky Transient Facility (ZTF). identify 38 candidates with durations above half-maximum light 1 d < t1/2 12 d, which 28 have (g-r<-0.2 mag) colors at peak light. Of (28 FBOTs), 19 (13) can be spectroscopically classified as core-collapse supernovae (SNe): 11 (8) H- or He-rich (Type II/IIb/Ib) SNe, 6 (4) interacting IIn/Ibn) and 2 (1) H&He-poor Ic/Ic-BL) SNe. Two FBOTs (published...
We present SN 2020jfo, a Type IIP supernova in the nearby galaxy M61. Optical light curves from Zwicky Transient Facility, complemented with data Swift and near-IR photometry are presented. The 350-day duration bolometric curve exhibits relatively short (~ 65 days) plateau. This implies moderate ejecta mass 5 Msun). A series of spectroscopy is presented, including spectropolarimetric observations. nebular spectra dominated by Halpha but also reveal emission lines oxygen calcium. Comparisons...