A5068443997- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Solar and Space Plasma Dynamics
- History and Developments in Astronomy
- Atmospheric Ozone and Climate
- Pulsars and Gravitational Waves Research
- Radio Astronomy Observations and Technology
- Galaxies: Formation, Evolution, Phenomena
- Particle Accelerators and Free-Electron Lasers
- Atomic and Molecular Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Dark Matter and Cosmic Phenomena
- Spectroscopy and Laser Applications
- Laser-Plasma Interactions and Diagnostics
- High-pressure geophysics and materials
- Geophysics and Gravity Measurements
- Calibration and Measurement Techniques
- Ionosphere and magnetosphere dynamics
- Adaptive optics and wavefront sensing
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2014-2023
University of Pisa
2014-2023
University of Würzburg
2023
National Institute for Astrophysics
2023
Charles University
2018-2019
Czech Academy of Sciences, Astronomical Institute
2013-2019
Istituto Nazionale di Fisica Nucleare
2017
Institut de Recherche en Astrophysique et Planétologie
2016
Université de Toulouse
2016
United States Naval Research Laboratory
2016
view Abstract Citations (286) References (74) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Goddard High-Resolution Spectrograph Observations of the Local Interstellar Medium and Deuterium/Hydrogen Ratio along Line Sight toward Capella Linsky, Jeffrey L. ; Brown, Alexander Gayley, Ken Diplas, Athanassios Savage, Blair D. Ayres, Thomas R. Landsman, Wayne Shore, Steven N. Heap, Sara HST observations 1216, 2600, 2800 A spectral regions are analyzed for...
view Abstract Citations (139) References (40) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Magnetically Controlled Circumstellar Matter in the Helium-strong Stars Shore, Steven N. ; Brown, Douglas This paper reports observation and interpretation of ultraviolet spectrum variations nine helium-strong stars: HD 36485, 37017, 37479, 37776, 58260, 60344, 64740, 96446, 133518. A unified model is developed to account for observed correlation among three stellar...
Within a molecular cloud, the strong ultraviolet radiation field produced by newly formed stars dissociates and ionizes surrounding gas. The radiative flux depends on effective temperature metallicity of star. Using most recent line-blanketed atmosphere models from Kurucz, we obtain rates ionizing dissociating photons with temperatures 7.5 × 103 to 5 104 K, for metallicities between 0.01 times solar solar. With transfer model, then compute basic structures sizes photoionized photodissociated...
Nova Mon 2012 was the first classical nova to be detected as a high energy $\gamma$-ray transient, by Fermi-LAT, before its optical discovery. We study time sequence of resolution echelle spectra (Nordic Optical Telescope) and contemporaneous NOT, STIS UV, CHIRON (Nov 20/21/22). use [O III] H$\beta$ line fluxs constrain properties ejecta. derive structure from UV profiles compare our measured fluxes for with predictions using Cloudy abundances other ONe novae. is confirmed an nova. find...
Mass loss is a key uncertainty in the evolution of massive stars. Stellar calculations must employ parametric algorithms for mass loss, and usually only include stellar winds. We carry out parameter study effects wind on star using open-source code MESA. provide systematic comparison solar-metallicity, nonrotating, single stars initial range $15-35\,M_\odot$. consider combinations drawn from two hot phase algorithms, three cool Wolf-Rayet algorithms. linear efficiency scale factors $1$,...
High-resolution spectroscopy has revealed large concentrations of CNO and sometimes other intermediate-mass elements in the shells ejected during nova outbursts, suggesting that solar composition material transferred from secondary mixes with outermost layers underlying white dwarf thermonuclear runaway. Multidimensional simulations have shown Kelvin-Helmholtz instabilities provide self-enrichment accreted envelope dwarf, at levels agree observations. However, Eulerian time-explicit nature...
On 2021 August 8, the recurrent nova RS Ophiuchi erupted again, after an interval of 15.5 yr. Regular monitoring by Neil Gehrels Swift Observatory began promptly, on 9.9 (0.37 day optical peak), and continued until source passed behind Sun at start November, 86 days later. Observations then restarted 197, once Oph emerged from constraint. This makes first Galactic to have been monitored throughout two eruptions. Here we investigate extensive X-ray datasets 2006 2021, as well more limited...
We report the Fermi-LAT gamma-ray detection of 2021 outburst symbiotic recurrent nova RS Ophiuchi. In this system, unlike classical novae from cataclysmic binaries, ejecta white dwarf form shocks when interacting with dense circumstellar wind environment red giant companion. find LAT spectra 50 MeV to ~20-23 GeV, highest-energy photons detected in some sub-intervals, are consistent $\pi^{\rm 0}$-decay emission as proposed by Tatischeff & Hernanz (2007) for its previous 2006 outburst. The...
Aims.This paper develops a method for obtaining the star formation histories of mixed, resolved population through use color-magnitude diagrams (CMDs). The provides insight into local rate, analyzing observations Hipparcos satellite comparison with synthetic CMDs computed different an updated stellar evolution library.
view Abstract Citations (98) References (38) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the Massive Star--forming Capacity of Molecular Clouds Franco, Jose ; Shore, Steven N. Tenorio-Tagle, Guillermo Assuming that photoionization is self-limiting process for continued star formation, we estimate maximum number massive (OB) stars can form within a molecular cloud. The most efficient cloud destruction mechanism in early stages H II region evolution...
The nova T Pyx was observed with high resolution spectroscopy (R ~ 65000) spectroscopy, beginning 1 day after discovery of the outburst and continuing through last visibility star at end May 2011. interstellar absorption lines Na I, Ca II, CH, CH$^+$, archival H I 21 cm emission line observations have been used to determine a kinematic distance. Interstellar diffuse features extinction independent previous assumptions. Sample Fe-peak profiles show optical depth radial velocity evolution...
Classical novae are thermonuclear explosions that take place in the envelopes of accreting white dwarfs binary systems. The material piles up under degenerate conditions, driving a runaway. energy released by suite nuclear processes operating at envelope heats to peak temperatures ~(1−4) × 108 K. During these events, about 10-3−10-7 M⊙, enriched CNO and, sometimes, other intermediate-mass elements (e.g., Ne, Na, Mg, Al) ejected into interstellar medium. To account for gross observational...
Abstract We detected an ionization flare on 2024 November 18 during a high cadence spectroscopic monitoring campaign T CrB ( https://aras-database.github.io/database/index.html ) before its anticipated next nova outburst with duration of between 12 and 32 days, which optical emission lines He ii [O iii ] appeared for the first time since end very active state 2015–2023.
LMC 91 was a very fast, classical nova and the brightest ever observed in Large Magellanic Cloud. It extensively during both its early optically thick nebular evolution optical UV wavelength regions. We successfully fit all spectra using grid of spherically symmetric, non-LTE, line-blanketed, expanding synthetic created with model atmosphere code PHOENIX. The emission lines have been fitted an optimization technique for emission-line luminosities predicted by photoionization CLOUDY. Our...
view Abstract Citations (82) References (36) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Physics of Early Nova Spectra Hauschildt, Peter H. ; Starrfield, Sumner Shore, Steven N. Allard, France Baron, E. We discuss the physical effects that are important for formation early spectra novae. atmospheres optically thick, fast expanding shells with flat density profiles, leading to geometrically very extended atmospheres. show properties nova can be...
The Goddard High Resolution Spectrograph (GHRS), currently in Earth orbit on the Hubble Space Telescope (HST), operates wavelength range 1150-3200 A with spectral resolutions (lambda/delta lambda) of approximately 2 x 10(exp 3), 4), and 1 3). instrument its development from inception, current status, approach to operations, representative results major areas scientific goals, prospects for future are described.
view Abstract Citations (80) References (17) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Early Ultraviolet Spectral Evolution of Nova Cygni 1992 Shore, Steven N. ; Sonneborn, George Starrfield, Sumner Riestra-Gonzalez, Rosario Ake, T. B. We report on the high resolution ultraviolet line profile evolution using International Explorer (IUE) satellite and Goddard High Resolution Spectrograph (GHRS) Hubble Space Telescope (HST). Our observations cover...
view Abstract Citations (84) References (44) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Colliding Stellar Winds in the Eclipsing Wolf-Rayet Binary V444 Cygni Shore, Steven N. ; Brown, Douglas High resolution spectra of have been obtained using International Ultraviolet Explorer Satellite. These span both eclipses and include one observation at third quadrature. Together with seven archival spectra, they provide reasonably complete phase coverage for...
V838 Her and V4160 Sgr were two of the fastest classical novae ever observed, exhibiting light curve declines 2 mag in less than days. Both also showed strong neon emission lines, indicative an outburst occurring on oxygen-neon-magnesium white dwarf. Being brighter two, has extensive set X-ray to radio observations obtained during its first year after outburst. a more modest ultraviolet optical spectra, which show it be similar Her, not just evolution but spectral development. The observed...
view Abstract Citations (90) References (104) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Geometry and Physical Conditions in the Stellar Wind of AG Carinae Leitherer, Claus ; Allen, Richard Altner, Bruce Damineli, Augusto Drissen, Laurent Idiart, Thais Lupie, Olivia Nota, Antonella Robert, Carmelle Schmutz, Werner Shore, Steven N. is one prototypes class Luminous Blue Variables (LBVs). Since 1990 star has continuously brightened its visual continuum. We...