Although many features of synchrotron radiation have been well known for a long time (e.g., [1]), there is certainly room for further improvements and developments. In a recent investigation [2], starting from Schwinger’s monumental work on synchrotron radiation [3] many years ago, an expicit expression for the mean number 〈N〉 of photons emitted per revolution was derived involving a remarkably simple one-dimensional integral. This allowed us to carry out a systematic analysis for high-energy charged particles. Our new expression is given by

High energy particles

AGILE is a small space mission of the Italian Space Agency (ASI) devoted to gamma-ray and hard-X astrophysics, successfully launched on April 23, 2007. The AGILE Payload is composed of three instruments: a gamma-ray imager based on a tungsten-silicon tracker (ST), for observations in the gamma ray energy range 30 MeV–50 GeV, a Silicon based X-ray detector, SuperAGILE (SA), for imaging in the range 18–60 keV and a CsI(Tl) Mini-Calorimeter (MCAL) that detects gamma rays or charged particles energy loss in the range 300 keV–100 MeV. MCAL is composed of 30 CsI(Tl) scintillator bars with photodiode readout at both ends, arranged in two orthogonal layers. MCAL can work both as a slave of the ST and as an independent gamma-ray detector for transients and gamma-ray bursts detection. In this paper a detailed description of MCAL is presented together with its performance.

Design and construction of the Mini-Calorimeter of the AGILE satellite

Photon-like particles are predicted in many extensions of the Standard Model. They have interactions similar to the photon, are vector bosons, and can be produced together with photons. The present paper proposes a search for such particles in the $ e^+e^- \to U\gamma$ process in a positron-on-target experiment, exploiting the positron beam of the DA$\Phi$NE linac at the Laboratori Nazionali di Frascati, INFN. In one year of running a sensitivity in the relative interaction strength down to $\sim10^{-6}$ is achievable, in the mass region from 2.5 MeV$<M_U<$ 20 MeV. The proposed experimental setup and the analysis technique is discussed.

Proposal to search for a dark photon in $e^+$ on target collisions at DA$\Phi$NE linac

The international Muon Ionization Cooling Experiment (MICE), which is under construction at the Rutherford Appleton Laboratory (RAL), will demonstrate the principle of ionization cooling as a technique for the reduction of the phase-space volume occupied by a muon beam. Ionization cooling channels are required for the Neutrino Factory and the Muon Collider. MICE will evaluate in detail the performance of a single lattice cell of the Feasibility Study 2 cooling channel. The MICE Muon Beam has been constructed at the ISIS synchrotron at RAL, and in MICE Step I, it has been characterized using the MICE beam-instrumentation system. In this paper, the MICE Muon Beam and beam-line instrumentation are described. The muon rate is presented as a function of the beam loss generated by the MICE target dipping into the ISIS proton beam. For a 1 V signal from the ISIS beam-loss monitors downstream of our target we obtain a 30 KHz instantaneous muon rate, with a neglible pion contamination in the beam.

/pdf/the-mice-muon-beam-on-isis-and-the-beam-line-instrumentation-3hcaqqb9df.pdf

The MICE Muon Beam on ISIS and the beam-line instrumentation of the Muon Ionization Cooling Experiment

We report the results of a systematic study of the time performance of triple-GEM detectors operated with Ar/CO 2 /CF 4 and Ar/CF 4 /iso-C 4 H 10 gas mixtures. This study and the detector development has been performed in the framework of an R&D activity on detectors for the innermost part (region R1) of the first muon station (M1) of the LHCb experiment. The use of fast gas mixtures allows to achieve a time resolution better than 5 ns (r.m.s.) and a single detector efficiency up to ∼ 99% in a 20 ns time window. Discharge studies have been performed at the π M1 hadron beam facility of the Paul Scherrer Institute. Local aging properties were investigated exposing the detector to a collimated 5.9 keV X-rays beam. The whole R&D activity with different gas mixtures has been performed with small 10×10 cm 2 triple-GEM detector prototypes. A full size prototype (module-0) constituted by two 20×24 cm 2 triple-GEM detectors, equipped with front-end electronics based on ASDQ chip, has been built and successfully tested, with the chosen Ar/CO 2 /CF 4 =45/15/40 gas mixture, at the electron test beam facility at the Laboratori Nazionali di Frascati.

High-rate particle triggering with triple-GEM detector

The DA NE Beam Test Facility (BTF) is a beam transfer line optimized for the production of a dened number of electrons or positrons, in a wide range of multiplicities and down to single-electron mode, in the energy range between 50 and 800 MeV. The typical pulse duration is 10 ns and the maximum repetition rate is 50 Hz. The facility is aimed mainly for detector calibration purposes. The BTF has been successfully commissioned in February 2002, and started operation in November of the same year. The schemes of operation, the commissioning results, as well as the rst users’ experience are here reported.

http://www.lnf.infn.it/sis/preprint/pdf/getfile.php?filename=LNF-03-3(P).pdf

P. Valente

Papers

Commissioning of the DA NE Beam Test Facility