Shashlik Calorimeter Research Articles

Study of response nonuniformity for the LHCb calorimeter module and the prototype of the CBM calorimeter module

A spatial nonuniformity of the response to high-energy muons is studied in the modules of the LHCb electromagnetic calorimeter and the prototype of the calorimeter module with lead plates and scintillator tiles 0.5 mm thick. The nonuniformity of the response of the inner LHCb modules to 50-GeV electrons is also measured. Software is developed for a thorough simulation of light collection in scintillator plates of a shashlik calorimeter. A model is elaborated to describe light transmission from the initial scintillation to the wavelength-shifting fiber with a subsequent reradiation and propagation of light over the fiber to the photodetector. The results of the simulation are in good agreement with data.

Testbeam results for a Shashlik calorimeter with longitudinal segmentation

In the frame of research and development for electromagnetic calorimetry at future e/sup +/e/sup -/ linear colliders, different techniques have been studied to implement longitudinal segmentation in Shashlik calorimeters. Two prototypes with 5/spl times/5 cm/sup 2/ lead/scintillator towers and readout by means of wavelength-shifting fibers have been built. The longitudinal segmentation of the shower is achieved by modifying the front part of the detector. In the first prototype, vacuum photodiodes have been inserted laterally for the first eight X/sub 0/, while in the second prototype a slow scintillator has been used in the first five X/sub 0/. Both of the prototypes have been exposed to beam at CERN. The performance in term of energy resolution, spatial resolution, and e//spl pi/ separation are described.

A shashlik calorimeter with longitudinal segmentation for a linear collider

Two techniques for longitudinal segmentation of shashlik calorimeters are proposed. Results concerning energy resolution and e/π separation are reported.

Shashlik calorimeter prototypes for a linear collider

Two techniques for longitudinal segmentation of shashlik calorimeters are proposed. Results concerning energy resolution, impact point reconstruction and e//spl pi/ separation are reported.

Testbeam results for a shashlik calorimeter with longitudinal segmentation

A novel technique for longitudinal segmentation of shashlik calorimeters has been tested in the CERN West Area beam facility. A 25 tower e.m. calorimeter has been built with vacuum photodiodes inserted in the first 8 radiation lengths to sample the initial development of the shower. Performance in terms of energy resolution, impact point reconstruction and e π separation are reported.

Performance of a shashlik calorimeter at LEPII

The Small Angle TIle Calorimeter (STIC) is a sampling lead-scintillator calorimeter, built with “shashlik’ technique. Results are presented from extensive studies of the detector performance at LEP.

An electromagnetic shashlik calorimeter with longitudinal segmentation

A novel technique for longitudinal segmentation of shashlik calorimeters has been tested in the CERN West Area beam facility. A 25 tower very fine samplings e.m. calorimeter has been built with vacuum photodiodes inserted in the first 8 radiation lengths to sample the initial development of the shower. Results concerning energy resolution, impact point reconstruction and electron/pion separation are reported.

Systematic study in high magnetic fields of fine-mesh photodetectors

The behaviour of fine-mesh Hamamatsu R2149-03 phototetrodes is studied inside magnetic fields up to 4 T, in view of possible applications as readout devices for shashlik calorimeters.

Beam test results of a Shashlik calorimeter in a high magnetic field

Abstract Shashlik calorimeter prototypes equipped with preshower detector have been tested in 3 T magnetic field with electron beam at CERN-SPS. The signal from electrons increases as much as 11% at 3 T magnetic field. No significant deterioration on the energy resolution as well as the preshower detector performance have been observed.

Energy and spatial resolution of a Shashlik calorimeter and a silicon preshower detector

New projective prototypes of a scintillator/lead sandwich type sampling calorimeter Shashlik with a silicon preshower detector have been constructed and tested with an electron beam at CERN-SPS. The energy resolution is measured to be 8.7% E( GeV ) in stochastic term, 0.330/ E (GeV) in noise term and 0.5% in constant term. The angular resolution is better than 70 mrad E( GeV ) .

The silicon shower maximum detector for the STIC

The structure of a shashlik calorimeter allows the insertion of tracking detectors within the longitudinal sampling to improve the accuracy in the determination of the direction of the showering particle and the eπ separation ability. The new forward calorimeter of the DELPHI detector has been equipped with two planes of silicon pad detectors respectively after 4 and 7.4 radiation lengths. The novelty of these silicon detectors is that to cope with the shashlik readout fibers, they had to incorporate 1.4 mm holes every cm2. The detector consists of circular strips with a radial pitch of 1.7 mm and an angular granularity of 22.5°, read out by means of the MX4 preamplifier. The preamplifier is located at 35 cm from the silicon detector and the signal is carried by Kapton cables bonded to the detector. The matching to the MX4 input pitch of 44 μm was made by a specially developed fanin hybrid.

Shashlik calorimeter Beam-test results

Results from an extensive study of nonprojective Shashlik calorimeter prototypes are reported. Nine (47 × 47 mm 2) towers were exposed to a high energy electron beam at CERN SPS and read out by silicon photodiodes followed by low noise preamplifiers. The main results are the measurements of the energy and shower position resolution and the angular resolution of the electron shower direction. The shower direction measurement is encouraging being in agreement at the tower center with a resolution of σ θ (mrad) = 70/√ E (10 mrad for 50 GeV electrons). The uniformity of the calorimeter response is found to be better than ± 1%. The mean light yield measured in Shashlik towers equipped with Kuraray Y7 WLS fibres and aluminized at the front end of the tower is of the order of 13 photons/MeV.

Shashlik calorimeter response to high energy electrons

We report the results coming from an extensive study of a Shashlik calorimeter prototype for CMS. Nine (47 × 47 mm 2) towers were exposed to a high energy electron beam at CERN SPS and read out by silicon photodiodes followed by low noise preamplifiers. The main results are the measurements of: • -|the energy resolution: σ E (%)= (8.4±0.1) E ⊕ (0.37±0.03) E ⊕(0.8±0.2) ; • -|the shower resolution: σ x,y(mm)= 9.1±0.3 stat±0.7 syst E ⊕ 27±1.4 stat±2.1 syst E . • -|We also give the angular resolution of the direction of an electron shower. It is estimated by using one point from a preshower detector located at 3 X 0 and the second point on a barycenter in the calorimeter mosaic. The result is encouraging being in agreement with a resolution of σ θ( mrad) = 70 √E , which gives for an electron of 50 GeV an angular resolution of 10 mrad. • -|The uniformity of the calorimeter response is found to be better than ± 1%. • -|The mean light yield measured in Shashlik towers equipped with Y7 WLS fibres from Kuraray and aluminized at the front side of the tower is of the order of 12300 γ/ GeV assuming a quantum efficiency of 62.5% for the Si photodiode.