The OPERA experiment Target Tracker Adam, T.; Baussan, E.; Borer, K. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2007, Letnik:
577, Številka:
3
Journal Article
Recenzirano
Odprti dostop
The main task of the Target Tracker detector of the long baseline neutrino oscillation OPERA experiment is to locate in which of the target elementary constituents, the lead/emulsion bricks, the ...neutrino interactions have occurred and also to give calorimetric information about each event. The technology used consists in walls of two planes of plastic scintillator strips, one per transverse direction. Wavelength shifting fibres collect the light signal emitted by the scintillator strips and guide it to both ends where it is read by multi-anode photomultiplier tubes. All the elements used in the construction of this detector and its main characteristics are described.
The neutrino oscillation OPERA experiment Target Tracker Baussan, E.; Borer, K.; Campagne, J.-E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2007, Letnik:
581, Številka:
1
Journal Article
Recenzirano
The main task of the Target Tracker of the long baseline neutrino oscillation OPERA experiment, is to locate in which of the target elementary constituents, the lead/emulsion bricks, the neutrino ...interactions have occurred and also to give calorimetric information about each event.
The technology used consists in walls of two planes of long plastic scintillator strips, one per transverse direction. Wavelength shifting fibres collect the light signal emitted by the scintillator strips and guide it to both ends where it is read by multi-anode photomultiplier tubes. The Target Tracker is composed of 62 scintillating walls of a total surface of about
6000
m
2
. Each wall is made by assembling 4 horizontal and 4 vertical modules of 64.7
m long, scintillating strips. This detector has observed the first neutrino interactions during August 2006.
In this paper we will describe all elements used for the construction and operation of this detector and we will also give its main characteristics.
Two special calorimeters are foreseen for the instrumentation of the very forward region of an ILC or CLIC detector; a luminometer (LumiCal) designed to measure the rate of low angle Bhabha ...scattering events with a precision better than 10\(^{-3}\) at the ILC and 10\(^{-2}\) at CLIC, and a low polar-angle calorimeter (BeamCal). The latter will be hit by a large amount of beamstrahlung remnants. The intensity and the spatial shape of these depositions will provide a fast luminosity estimate, as well as determination of beam parameters. The sensors of this calorimeter must be radiation-hard. Both devices will improve the e.m. hermeticity of the detector in the search for new particles. Finely segmented and very compact electromagnetic calorimeters will match these requirements. Due to the high occupancy, fast front-end electronics will be needed. Monte Carlo studies were performed to investigate the impact of beam-beam interactions and physics background processes on the luminosity measurement, and of beamstrahlung on the performance of BeamCal, as well as to optimise the design of both calorimeters. Dedicated sensors, front-end and ADC ASICs have been designed for the ILC and prototypes are available. Prototypes of sensor planes fully assembled with readout electronics have been studied in electron beams.
To improve the identification and separation of leptons in the hadron calorimeter of DELPHI, one of the four LEP experiments at CERN, the possibility of a direct read-out of the cathodes of the ...20,000 limited streamer tubes was studied and successfully tested on a small scale. A larger scale test started in June 1994. This new system which is independent of the present pad read-out provides a "yes/no" information. The combination of both read-out systems makes it possible to use the hadron calorimeter as a track detector. The result of these tests show that the cathode read-out provides a better /spl pi///spl mu/ separation, and improved detection of neutral long lived particles, enhanced discrimination of two showers and a more precise hadron energy measurement. It was decided to equip the whole detector with the new read-out, starting during the 94/95 shutdown.< >
The DELPHI Hadron Calorimeter was conceived more than ten years ago, as an instrument to measure the energy of hadrons and hadronic jets from e/sup +/e/sup -/collisions at the CERN collider LEP. In ...addition it was expected to provide a certain degree of discrimination between pions and muons. The detector is a rather simple and relatively inexpensive device consisting of around 20,000 limited streamer plastic tubes, with inductive pad read-out, embedded in the iron yoke of the 1.2 T DELPHI magnet. Its depth is at minimum 6.6 nuclear interaction lengths. The electronics necessary for the pad readout was designed to have an adequate performance for a reasonable cost. This detector has proved over six years of operation to have an entirely satisfactory performance and great reliability; for example less than 1% of the streamer tubes have failed and electronic problems remain at the per mil level. During the past two years an improvement programme has been under way. It has been found possible to use the streamer tubes as strips, hence giving better granularity and particle tracking, by reading out the cathode of individual tubes. The constraints on this were considerable because of the inaccessibility of the detectors in the magnet yoke. However a cheap and feasible solution has been found. The cathode readout leads to an improved energy resolution, better /spl mu/ identification, a better /spl pi///spl mu/ separation and to possibilities of neutral particle separation. The simultaneous anode read-out of several planes of the endcaps of the detector will provide a fast trigger in the forward/backward direction which is an important improvement for LEP200. On the barrel the system will provide a cosmic trigger which is very useful for calibration as counting rates at LEP200 will be very low.