A5049143016- Particle Detector Development and Performance
- Laser-Matter Interactions and Applications
- Calibration and Measurement Techniques
- Spectroscopy and Quantum Chemical Studies
- Nuclear Physics and Applications
- Spacecraft Design and Technology
- Advanced Chemical Physics Studies
- Radiation Detection and Scintillator Technologies
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Mass Spectrometry Techniques and Applications
- Spectroscopy and Laser Applications
- Spacecraft and Cryogenic Technologies
- Photochemistry and Electron Transfer Studies
- Ionosphere and magnetosphere dynamics
- Medical Imaging Techniques and Applications
- Adaptive optics and wavefront sensing
- Geophysics and Gravity Measurements
- Lightning and Electromagnetic Phenomena
- Advanced Electrical Measurement Techniques
- Spacecraft Dynamics and Control
- History and advancements in chemistry
- Advanced Frequency and Time Standards
- Space Satellite Systems and Control
Sapienza University of Rome
2024
DTU Space
2019-2020
Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo
2020
Osservatorio di Astrofisica e Scienza dello Spazio
2020
Rutherford Appleton Laboratory
2020
Technical University of Denmark
2001-2019
Institut d'Estudis Espacials de Catalunya
2014
California Institute of Technology
1992-1996
The JEM–X monitor provides X-ray spectra and imaging with arcminute angular resolution in the 3 to 35 keV band. good low energy response of plays an important role identification gamma ray sources analysis scientific interpretation combined data. is a coded aperture instrument consisting two identical, coaligned telescopes. Each detectors has sensitive area 500 cm2, views sky through its own mask. masks are inverted respect each other 3' across effective field view about 10° diameter.
Direct studies of diradicals, the molecular species hypothesized to be archetypal chemical bond transformations in many classes reactions, have been made using femtosecond laser techniques with mass spectrometry a beam. These are aimed at "freezing" diradicals time and course reaction. The passage these through transition-state region was observed effect total energy alkyl substitution on rates closure cleavage examined. results establish nature intermediates define their existence during reactions.
The real-time dynamics of hydrogen-atom-transfer processes under collisionless conditions are studied using femtosecond depletion techniques. experiments focus on the methyl salicylate system, which exhibits ultrafast hydrogen motion between two oxygen atoms due to molecular tautomerization, loosely referred as intramolecular ‘‘proton’’ transfer. To test for tunneling and mass effects excited potential surface, we also deuterium methyl-group substitutions. We observe that hydrogen,...
Degenerate four-wave mixing (DFWM), using ∼60 femtosecond (fs) laser pulses, is introduced to study transition-state dynamics of chemical reactions in the gas phase. The ultrafast techniques are applied a range systems, atomic, unimolecular, and bimolecular. It shown how fs DFWM can be incorporated different temporal pulse schemes extract dynamics. beams configured folded boxcar geometry, producing spatially separated, background-free, signal pulse. Aspects technique, such as absorption,...
The femtosecond real-time dynamics of the isomerization reaction trans-stilbene under collisionless conditions are studied using (2+1) resonance-enhanced multiphoton ionization (REMPI) and depletion spectroscopy (FDS) in a pump−probe scheme. observed transients reflect macroscopic sample anisotropy decay (rotational coherence) intramolecular vibrational energy redistribution (IVR) as well ethylenic twisting reaction. Polarization-resolved measurements performed to isolate influence...
When a reaction involving two equivalent bonds has sufficient energy to break both of them, it can proceed by either concerted or stepwise mechanism. For Norrish type-I and other reactions, this issue been controversial since direct time resolution the individual C–C cleavage events was not possible. Here, for elementary α-cleavage acetone, we report on femtosecond intermediates using mass spectrometry. The results show nonconcertedness reaction, provide times primary secondary breakage,...
We report the femtosecond dynamics of vibrational motion in transition-state evolution an isomerization reaction. The observed nonstatistical and bound behavior reflects localization selective torsional bending modes (of 72 normal system). multidimensionality potential energy surface is examined by comparing experiments with theoretical calculations.
Precision phase readout of optical beat note signals is one the core techniques required for intersatellite laser interferometry. Future space based gravitational wave detectors like eLISA require such a over wide range MHz frequencies, due to orbit induced Doppler shifts, with precision in order μrad/√Hz at frequencies between 0.1 mHz and 1 Hz. In this paper, we present systems, so-called phasemeters, that are able achieve precisions discuss various means have been employed reduce noise...
Ariel, the Atmospheric Remote-sensing Infrared Exoplanet Large-survey, was adopted as fourth medium-class mission in ESA's Cosmic Vision programme to be launched 2029. During its 4-year mission, Ariel will study what exoplanets are made of, how they formed and evolve, by surveying a diverse sample of about 1000 extrasolar planets, simultaneously visible infrared wavelengths. It is first dedicated measuring chemical composition thermal structures hundreds transiting exoplanets, enabling...
The Modular X- and Gamma-ray Sensor (MXGS) is an imaging spectral instrument mounted on the starboard side of Columbus module International Space Station. Together with Multi-Spectral Imaging Assembly (MMIA) (Chanrion et al. this issue) MXGS constitutes instruments Atmosphere-Space Interactions Monitor (ASIM) (Neubert issue). main objectives are to image measure spectrum $\gamma $ -rays from lightning discharges, known as Terrestrial Flashes (TGFs), for MMIA perform high speed photometry...
THESEUS (Transient High Energy Sky and Early Universe Surveyor) is one of the three missions selected by ESA as fifth medium class mission (M5) candidates in its Cosmic Vision science program, currently under assessment a phase A study with planned launch date 2032. designed to carry on-board two wide deep sky monitoring instruments for X/gamma-ray transients detection: wide-field soft X-ray monitor imaging capability (Soft Imager, SXI, 0.3 – 5 keV), hard X-ray, partially-imaging...
The Ariel space mission will characterize spectroscopically the atmospheres of a large and diverse sample hundreds exoplanets. Through study targets with wide range planetary parameters (mass, density, equilibrium temperature) host star types origin for diversity observed in known exoplanets be better understood. is an ESA Medium class science (M4) spacecraft bus developed by industry under contract to ESA, Payload provided consortium national funding agencies member states, plus...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFemtosecond real-time probing of reactions. 12. Vectorial dynamics transition statesT. Baumert, S. Pedersen, and A. H. ZewailCite this: J. Phys. Chem. 1993, 97, 48, 12447–12459Publication Date (Print):December 1, 1993Publication History Published online1 May 2002Published inissue 1 December 1993https://pubs.acs.org/doi/10.1021/j100150a002https://doi.org/10.1021/j100150a002research-articleACS PublicationsRequest reuse permissionsArticle...
LOFT (Large Observatory For x-ray Timing) is one of the ESA M3 missions selected within Cosmic Vision program in 2011 to carry out an assessment phase study and compete for a launch opportunity 2022-2024. The phase-A studies all were completed at end 2013. designed on-board two instruments with sensitivity 2-50 keV range: 10 m<sup>2</sup> class Large Area Detector (LAD) <1° collimated FoV wide field monitor (WFM) making use coded masks providing instantaneous coverage more than 1/3 sky....
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFemtosecond real-time probing of reactions. 13. Multiphoton dynamics mercury iodide (IHgI)S. Pedersen, T. Baumert, and A. H. ZewailCite this: J. Phys. Chem. 1993, 97, 48, 12460–12465Publication Date (Print):December 1, 1993Publication History Published online1 May 2002Published inissue 1 December 1993https://doi.org/10.1021/j100150a003RIGHTS & PERMISSIONSArticle Views125Altmetric-Citations17LEARN ABOUT THESE METRICSArticle Views are the...
We summarize the inflight performance of JEM–X, X–ray monitor on INTEGRAL mission during initial ten months operations. The JEM–X instruments have now been tuned to stable operational conditions. is found be close pre-launch expectations. ground calibrations and calibration data permit determine characteristics fully support scientific analysis.
The X and Gamma Imaging Spectrometer instrument on-board the THESEUS mission (selected by ESA in framework of Cosmic Vision M5 launch opportunity, currently phase A) is based on a detection plane composed several thousands single active elements. Each element comprises 4.5×4.5×30 mm<sup>3</sup> CsI(Tl) scintillator bar, optically coupled at both ends to Silicon Drift Detectors (SDDs). SDDs acts as photodetectors for scintillation light direct X-ray sensors. In this paper design XGIS...
An elegant breadboard model of the LISA phasemeter is currently under development by a Danish-German consortium. The build in frame an ESA technology activity to demonstrate feasibility and readiness metrology baseline architecture. This article gives overview about design its components, including distribution key functionalities.
LOFT (Large Observatory For x-ray Timing) is one of the ESA M3 missions selected within Cosmic Vision program in 2011 to carry out an assessment phase study and compete for a launch opportunity 2022-2024. The phase-A studies all were completed at end 2013. designed on-board two instruments with sensitivity 2-50 keV range: 10 m class Large Area Detector (LAD) <1° collimated FoV wide field monitor (WFM) making use coded masks providing instantaneous coverage more than 1/3 sky. prime goal WFM...
The INTEGRAL X-ray monitor, JEM-X, (together with the two gamma ray instruments, SPI and IBIS) provides simultaneous imaging arcminute angular resolution in 3-35 keV band. good low energy response of JEM-X plays an important role detection identification sources as well analysis scientific interpretation combined data. is a coded aperture telescope consisting identical detectors. Each detector has sensitive area 500 cm<sup>2</sup>, views sky through its own mask. masks are located 3.4 m...