A. Ciaravella
A5056028507- Solar and Space Plasma Dynamics
- Stellar, planetary, and galactic studies
- Ionosphere and magnetosphere dynamics
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Atmospheric Ozone and Climate
- Advanced Chemical Physics Studies
- Molecular Spectroscopy and Structure
- Calibration and Measurement Techniques
- Atomic and Molecular Physics
- Astronomy and Astrophysical Research
- Geophysics and Gravity Measurements
- Spacecraft Design and Technology
- Spacecraft and Cryogenic Technologies
- Geomagnetism and Paleomagnetism Studies
- Gamma-ray bursts and supernovae
- Laser-induced spectroscopy and plasma
- Superconducting and THz Device Technology
- Atmospheric chemistry and aerosols
- Superconducting Materials and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- High-pressure geophysics and materials
- Orbital Angular Momentum in Optics
- Atmospheric and Environmental Gas Dynamics
- Spectroscopy and Laser Applications
Osservatorio Astronomico di Palermo
2013-2023
National Institute for Astrophysics
2003-2022
Astronomical Observatory of Rome
2019
Center for Astrophysics Harvard & Smithsonian
1998-2010
SRON Netherlands Institute for Space Research
2010
University of Palermo
1993-2006
Max Planck Institute for Solar System Research
2006
United States Air Force Research Laboratory
2005
Harvard University
1998-2003
University of Palermo
2003
We present a self-consistent empirical model for several plasma parameters of polar coronal hole near solar minimum, derived from observations with the Solar and Heliospheric Observatory Ultraviolet Coronagraph Spectrometer. The describes radial distribution density electrons, H0, O5 + outflow velocity unresolved most probable velocities H0 during period between 1996 November 1997 April. In this Letter, we compare H I Lyα O VI λλ1032, 1037 emission lines spatial models parameters, iterate...
Metis is the first solar coronagraph designed for a space mission capable of performing simultaneous imaging off-limb corona in both visible and UV light. The observations obtained with aboard Solar Orbiter ESA-NASA observatory will enable us to diagnose, unprecedented temporal coverage spatial resolution, structures dynamics full from 1.7 $R_\odot$ about 9 $R_\odot$. Due uniqueness profile, be able observe close vantage point (down 0.28 AU), achieving out-of-ecliptic views increase orbit...
We present a comprehensive and self-consistent empirical model for several plasma parameters in the extended solar corona above polar coronal hole. The is derived from observations with SOHO Ultraviolet Coronagraph Spectrometer (UVCS/SOHO) during period between 1996 November 1997 April. compare of H I Lyα O VI λλ1032, 1037 emission lines detailed three-dimensional models iterate optimal consistency measured synthesized observable quantities. Empirical constraints are obtained radial...
In the wake of 2003 November 4 coronal mass ejection associated with largest solar flare last sunspot cycle, a current sheet (CS) was observed by Ultraviolet Coronagraph Spectrometer (UVCS) as narrow bright feature in [Fe XVIII] (106.8 K) line. This is first UV observation which CS evolution followed from its onset. spectra provide diagnostics electron temperature, emission measure, Doppler shift, line width, and size function time. Since UVCS slit inside Mark IV K-coronameter (MK4) field...
A peculiar young active region was observed in 1998 March with the Ultraviolet Coronagraph Spectrometer (UVCS) over southwest limb. The spectra showed strong emission λ974 line of fluorine-like iron, [Fe XVIII], which is brightest at an electron temperature 106.8 K, and lines Ne IX, [Ca XIV], XV], Fe XVII, [Ni XV]. It only so far to show such high temperatures 0.5 R☉ above solar We derive measure estimate elemental abundances. produced a number coronal mass ejections (CMEs). After one CME on...
We describe a coronal mass ejection (CME) observed on 1999 April 23 by the Ultraviolet Coronagraph Spectrometer (UVCS), Extreme-Ultraviolet Imaging Telescope (EIT), and Large-Angle Spectrometric Coronagraphs (LASCO) aboard Solar Heliospheric Observatory (SOHO). In addition to O VI C III lines typical of UVCS spectra CMEs, this 480 km s-1 CME exhibits forbidden intercombination V at λλ1213.8 1218.4. The relative intensities represent an accurate electron density diagnostic not generally...
The investigation of the wind in solar corona initiated with observations resonantly scattered UV emission coronal plasma obtained UVCS-SOHO, designed to measure outflow speed by applying Doppler dimming diagnostics. Metis on Solar Orbiter complements UVCS spectroscopic observations, performed during activity cycle 23, simultaneously imaging polarized visible light and HI Ly-alpha order obtain high-spatial temporal resolution maps outward velocity continuously expanding atmosphere. May 15,...
A 1200 km s −1 Coronal Mass Ejection was observed with the SOHO instruments EIT, LASCO and UVCS on June 11, 1998. Simultaneously, Type II radio bursts were WAVES experiment aboard Wind spacecraft at 4 MHz by ground‐based metric wavelengths. The density in shock wave implied higher frequency is close to that inferred from SOHO/UVCS experiment. drift rates of suggest speeds lower than speed derived observations. spectrum shows enhanced emission lines O 5+ Si 11+ , consistent modest compression...
The Ultraviolet Coronagraph Spectrometer (UVCS) aboard the {\it SOHO} satellite has observed very fast Coronal Mass Ejections (CMEs) associated with X-class flares. These events show spectral signatures different than those seen in most other CMEs terms of rapid disruption pre-CME streamer, high Doppler shifts and temperature plasma visible [Fe XVIII] emission line. This paper describes three similar on 21 April, 23 July 24 August 2002 We determine physical parameters streamers discuss...
The EUV Imaging Telescope (EIT), Large Angle Spectrometric Coronagraph (LASCO), and Ultraviolet Spectrometer (UVCS) instruments aboard the SOHO satellite observed a prominence eruption (coronal mass ejection) on 1997 December 12. Ejected plasma moved at about 130 km s-1 in plane of sky showed Doppler shifts between -350 +30 s-1. appeared as strongly curved arch EIT images low corona. Emission ions ranging from Si III to O VI UVCS spectra indicates temperature range 104.5 105.5 K. morphology...
Pure methanol ices have been irradiated with monochromatic soft X-rays of 300 and 550 eV close to the 1s resonance edges C O, respectively, a broadband spectrum (250–1200 eV). The infrared (IR) spectra show several new products astrophysical interest such as CH2OH, H2CO, CH4, HCOOH, HCOCH2OH, CH3COOH, CH3OCH3, HCOOCH3, (CH2OH)2, well HCO, CO, CO2. effect is result combined interactions photons electrons ice. A significant contribution formation growth species in CH3OH ice given by secondary...
<i>Aims. <i/>We study the relative role of EUV and X-ray radiation in heating hydrogen-rich planet atmospheres with different composition electron content.<i>Methods. <i/>An accurate photo-ionization model has been used to follow primary photo-electron energy deposition throughout atmosphere.<i>Results. <i/>Heating rates efficiencies have computed, together column density cut-offs at which photons given energies stop their production inside atmosphere. Assuming 100 eV as borderline between...
Eruption of a coronal mass ejection (CME) drags and "opens" the magnetic field, presumably leading to formation large-scale current sheet field relaxation by reconnection. We analyze physical characteristics ray-like features formed in aftermath CMEs, check if interpretation this phenomenon terms reconnecting is consistent with observations. The study focused on measurements ray width, density excess, velocity as function radial distance. morphology rays indicates that they occur consequence...
METIS, the "Multi Element Telescope for Imaging and Spectroscopy", is a coronagraph selected by European Space Agency to be part of payload Solar Orbiter mission launched in 2017. The unique profile this will allow 1) close approach Sun (up 0.28 A.U.) thus leading significant improvement spatial resolution; 2) quasi co-rotation with Sun, resulting observations that nearly freeze several days large-scale outer corona plane sky 3) unprecedented out-of-ecliptic view solar corona. This paper...
Little is known about the effects of X-rays in interstellar ices. To understand sulfur depletion dense clouds and presence S2 comets, we simulated experimentally soft X-ray processing (0.3 keV) H2S ice for first time. Experiments were performed under ultrahigh vacuum conditions at 8 K using infrared quadrupole mass spectrometry to monitor solid gas phases, respectively. A UV irradiation experiment a similar dose was made comparison. After irradiation, an absorption appears near 4.0 μm which...