27 research outputs found
Absolute Fluorescence Spectrum and Yield Measurements for a wide range of experimental conditions
For the JEM-EUSO CollaborationThe fluorescence yield is a key ingredient in cosmic ray energy determination. It is sensitive to pressure, temperature and humidity. Up to now the fluorescence yield of the brightest line at 337 nm has been measured in an absolute way in one set of conditions, whereas fluorescence yields at the other wavelengths have been relatively measured for different conditions. Thus, absolute calibration for all the lines is unclear. We will do all measurements at once using the same apparatus: all the lines will be measured absolutely and not relatively for all conditions. For that we will use the 3-5 MeV electron beam of the PHIL accelerator (Photon Injector at LAL), shooting in a box filled with air at varying pressures, temperatures and humidity. Delta rays resulting from the beam collisions with Nitrogen are responsible for the light yield. The light detection probability should be independent of its emission point especially at the delta ray stopping point. The idea is to use an integrating sphere, encapsulated in a vessel where pressure, temperature and humidity can be varied. This sphere will have two ports for the beam (in and out), one more port dedicated to a NIST photodiode for calibration and another port feeding optical fibers going to: A) a grating spectrometer equipped with cooled CCD. B) a photomultiplier with BG3 filters to measure directly the integrated yield. Calibrations at the percent level, will give each line spectrum yields with a precision between 2 to 5%. A special issue will be to estimate the leakage due to "high energy" delta rays. Thus, we the air density will be increased, the beam energy will be lowered until the beam stops inside the sphere. Then, the energy loss will be precisely derived from the Bethe-Bloch formula. We will present the set-up
PHIL Accelerator at LAL - Diagnostic status
http://accelconf.web.cern.ch/AccelConf/BIW2010/papers/tupsm100.pdfInternational audienceThe "Photo-Injector at LAL" (PHIL : http://phil.lal.in2p3.fr/) is a new electron beam accelerator at LAL. This accelerator is dedicated to test and characterise electron photo-guns and high-frequency structures for future accelerator projects (like the next generation lepton colliders, CLIC, ILC). This machine has been designed to produce low energy (E<10 MeV), small emittance (epsilon < 10 pi.mm.mrad), high current (charge 2 nC/bunch) electrons bunch at low repetition frequency (frep<10Hz) [1]. The first beam has been obtained on the 4th of November 2009. This paper will describe the current status and the futures developments of the diagnostics devices on this machine
Low Energy Beam Measurements Using PHIL Accelerator at LAL, Comparison with PARMELA Simulations
http://accelconf.web.cern.ch/AccelConf/PAC2011/papers/wep210.pdfInternational audiencePHIL ("PHoÂto-InÂjecÂtor at LAL") is a new elecÂtron beam acÂcelÂerÂaÂtor at LAL. This acÂcelÂerÂaÂtor is dedÂiÂcatÂed to test and charÂacÂterÂize elecÂtron RF-guns and to deÂlivÂer elecÂtron beam to users. This maÂchine has been deÂsigned to proÂduce and charÂacÂterise low enÂerÂgy (E<10 MeV), small emitÂtance (e<10 p.​mm.​mrad), high brilÂliance elecÂtrons bunch at low repÂeÂtiÂtion freÂquenÂcy (n<10Hz). The first beam has been obÂtained on the 4th of NovemÂber 2009. The curÂrent RF-gun testÂed on PHIL is the AlÂphaX gun, a 2.5 cell S-band cavÂiÂty deÂsigned by LAL for the plasÂma acÂcelÂerÂaÂtor studÂies perÂformed at the StrathÂclyde uniÂverÂsiÂty. This paper will preÂsent the first AlÂphaX RF-gun charÂacÂterÂiÂzaÂtions perÂformed at LAL on PHIL acÂcelÂerÂaÂtor, and will show comÂparÂisons beÂtween meaÂsureÂments and PARMELA simÂuÂlaÂtions
PHIL photoinjector test line
LAL is now equiped with its own platform for photoinjectors tests and
Research and Developement, named PHIL (PHotoInjectors at LAL). This facility
has two main purposes: push the limits of the photoinjectors performances
working on both the design and the associated technology and provide a low
energy (MeV) short pulses (ps) electron beam for the interested users. Another
very important goal of this machine will be to provide an opportunity to form
accelerator physics students, working in a high technology environment. To
achieve this goal a test line was realised equipped with an RF source, magnets
and beam diagnostics. In this article we will desrcibe the PHIL beamline and
its characteristics together with the description of the first two
photoinjector realised in LAL and tested: the ALPHAX and the PHIN RF Guns
The ThomX project status
Work supported by the French Agence Nationale de la recherche as part of the program EQUIPEX under reference ANR-10-EQPX-51, the Ile de France region, CNRS-IN2P3 and Université Paris Sud XI - http://accelconf.web.cern.ch/AccelConf/IPAC2014/papers/wepro052.pdfA collaboration of seven research institutes and an industry has been set up for the ThomX project, a compact Compton Backscattering Source (CBS) based in Orsay - France. After a period of study and definition of the machine performance, a full description of all the systems has been provided. The infrastructure work has been started and the main systems are in the call for tender phase. In this paper we will illustrate the definitive machine parameters and components characteristics. We will also update the results of the different technical and experimental activities on optical resonators, RF power supplies and on the electron gun
Conception et réalisation d’une valise de transfert de photocathodes pour le Projet PHIL (LAL) et CTF3 (CERN)
International audienceL’élaboration de photocathode (CsTe) à haut rendement quantique demande souvent une enceinte de dépôt dévolu et en ultravide. Ces photocathodes sont très sensibles à la pollution et demande donc à être transporter sur les photo-injecteurs ou pour des analyses de surfaces sous un vide de qualité et à une pression inférieure à 10-9mbar. Cette valise doit donc répondre à de nombreuses contraintes mécaniques, d’encombrement, de course transverse et longitudinale, de poids, d’étuvage, d’autonomie et d’ultravide. La conception et la réalisation seront présentées ainsi que les résultats obtenus sur PHIL et sur CTF3