902 research outputs found
Application of novel techniques for interferogram analysis to laser-plasma femtosecond probing
Recently, two novel techniques for the extraction of the phase-shift map
(Tomassini {\it et.~al.}, Applied Optics {\bf 40} 35 (2001)) and the electronic
density map estimation (Tomassini P. and Giulietti A., Optics Communication
{\bf 199}, pp 143-148 (2001)) have been proposed. In this paper we apply both
methods to a sample laser-plasma interferogram obtained with femtoseconds probe
pulse, in an experimental setup devoted to laser particle acceleration studies.Comment: Submitted to Laser and Particle Beam
The laser-matter interaction meets the high energy physics: Laser-plasma accelerators and bright X/gamma-ray sources
Laser matter interaction in the regime of super-intense and ultra-short laser pulses is discovering common interests and goals for plasma and elementary particles physics. Among them, the electron laser wakefield acceleration and the X/Îł tunable sources, based on the Thomson scattering (TS) of optical photons on accelerated electrons, represent the most challenging applications. The activity of the Intense Laser Irradiation Laboratory in this field will be presented
Analysis of space-resolved X-ray spectra from laser plasmas
High dynamic range, space-resolved X-ray spectra, obtained
using a TlAP crystal and a cooled CCD camera as a detector,
were used to investigate the electron density and temperature
profiles of an aluminum laser plasma with micrometer resolution.
The electron density profile retrieved from the measurements
is compared with numerical predictions from the two hydrodynamics
codes MEDUSA (1D) and POLLUX (2D). It is shown that 2D density
profiles can be successfully reproduced by 1D simulations using
a spherical geometry with an ad hoc initial radius, leading
to similar electron temperature profiles
Ray-tracing simulations of a bent crystal X-ray optics for imaging using laser-plasma X-ray sources
Ray-tracing simulations of an optical X-ray system based on a spherically bent crystal operating in Bragg configuration for monochromatic projection imaging of thin samples are presented, obtained using a code developed for that purpose. The code is particularly suited for characterizing experimental arrangements routinely used with laser-produced plasma X-ray sources. In particular, the spatial resolution of the imaging system was investigated and a careful study of the complex pattern of the X-ray backlighting beam was performed
Line spectroscopy with spatial resolution of laser-plasma X-ray emission
High dynamic range, space-resolved X-ray spectra of an
aluminum laser–plasma in the 5.5–8 Å
range were obtained using a TlAP crystal and a cooled CCD
camera as a detector. This technique was used to investigate
the emission region in the longitudinal direction over
a distance of approximately 350 ÎĽm from the solid target
surface. These data show that the electron density profile
varies by two orders of magnitude with the temperature
ranging from about 180 eV in the overdense region to about
650 eV in the underdense region. Accordingly, different
equilibria take place across the explored region which
can be identified with this experimental technique. Detailed
studies on highly ionized atomic species in different plasma
conditions can therefore be performed simultaneously under
controlled conditions
Where next for the electricity distribution system operator? Evidence from a survey of European DSOs and National Regulatory Authorities
This paper seeks to shed light on the nature of optimal regulation of the electricity distribution system operator (DSO) over the period to 2025 and beyond, following the implementation of the EU Clean Energy Package and its constituent parts: Electricity Regulation (EU) 2019/943 and Electricity Directive (EU) 2019/944. We conducted two parallel surveys of DSOs and their national regulatory authorities (NRAs) across 39 European countries. This produced 39 responses from DSOs and 12 responses from NRAs covering, respectively, 40% and 78% of customers in those countries. We asked both DSOs and NRAs three sets of questions related to: (1) the definition and regulation of the future system operator function of the DSO; (2) lessons learned from transmission system operator (TSO) regulation that can be translated to the DSO; and (3) the way in which regulators support the capacity of the DSO to operate and coordinate the system. Our findings are consistent with the observation that the move towards a more active role for the DSO remains work in progress for both DSOs and their NRAs, given the fact that the Clean Energy Package has only passed into European Law relatively recently and some Member States are still implementing its provisions
Soft laser-plasma X-ray source for differential absorption imaging of tracing elements in thin samples
The differential imaging technique is particularly suitable for the
detection of small concentrations of contrasts agents for biological
and medical applications in samples using X-ray radiography. In this
paper, we present an application of this technique using a laser-plasma
soft X-ray source combined with a bent crystal. Using a Fresnel plate
as a test object, we were able to obtain spatial resolutions of the
order of a few tens of microns. The use of our configuration to perform
differential imaging of a test-sample at the L2 edge of Br
at 1,596 eV is finally demonstrated
Optimal cruise performance of a conventional helicopter
This article presents an analytical framework for investigating the cruise performance of conventional helicopter configurations. Starting from the analysis of power required in straight-and-level flight, endurance and range performance of turbine- and battery-powered rotorcraft are considered, for which it is assumed that fuel consumption and constant-power battery discharge models are, respectively, made available. The original contributions of the article are represented by (a) a closed-form formulation for expected endurance and range for both classes of vehicles, where electrical helicopters have not been dealt with in previous studies and (b) the analytical derivation of an accurate estimate for best endurance and best range airspeeds as a function of relevant system parameters. The approach is validated by analyzing two reference helicopters, showing good physical insight and better accuracy with respect to other techniques available in the literature, for the identification of an energy-efficient cruise flight strategy
Acceleration with Self-Injection for an All-Optical Radiation Source at LNF
We discuss a new compact gamma-ray source aiming at high spectral density, up
to two orders of magnitude higher than currently available bremsstrahlung
sources, and conceptually similar to Compton Sources based on conventional
linear accelerators. This new source exploits electron bunches from
laser-driven electron acceleration in the so-called self-injection scheme and
uses a counter-propagating laser pulse to obtain X and gamma-ray emission via
Thomson/Compton scattering. The proposed experimental configuration inherently
provides a unique test-bed for studies of fundamental open issues of
electrodynamics. In view of this, a preliminary discussion of recent results on
self-injection with the FLAME laser is also given.Comment: 8 pages, 10 figures, 44 references - Channeling 2012 conferenc
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