231 research outputs found
QCALT: a tile calorimeter for KLOE-2 upgrade
The upgrade of the DANE machine layout requires a modification of the
size and position of the inner focusing quadrupoles of KLOE-2 thus asking for
the realization of two new calorimeters covering the quadrupoles area. To
improve the reconstruction of events with photons hitting the
quadrupoles a calorimeter with high efficiency to low energy photons (20-300
MeV), time resolution of less than 1 ns and space resolution of few cm, is
needed. To match these requirements, we are designing a tile calorimeter,
QCALT, where each single tile is readout by mean of SiPM for a total
granularity of 2400 channels. We show first tests of the different calorimeter
components
Characterization and Performance of PADME's Cherenkov-Based Small-Angle Calorimeter
The PADME experiment, at the Laboratori Nazionali di Frascati (LNF), in
Italy, will search for invisible decays of the hypothetical dark photon via the
process , where the escapes detection. The
dark photon mass range sensitivity in a first phase will be 1 to 24 MeV. We
report here on measurement and simulation studies of the performance of the
Small-Angle Calorimeter, a component of PADME's detector dedicated to rejecting
2- and 3-gamma backgrounds. The crucial requirement is a timing resolution of
less than 200 ps, which is satisfied by the choice of PbF crystals and the
newly released Hamamatsu R13478UV photomultiplier tubes (PMTs). We find a
timing resolution of 81 ps (with double-peak separation resolution of 1.8 ns)
and a single-crystal energy resolution of 5.7%/ with light yield of
2.07 photo-electrons per MeV, using 100 to 400 MeV electrons at the Beam Test
Facility of LNF. We also propose the investigation of a two-PMT solution
coupled to a single PbF crystal for higher-energy applications, which has
potentially attractive features.Comment: 12 pages, 19 figures. v2: added section on radiation damage studie
Energy and time resolution for a LYSO matrix prototype of the Mu2e experiment
We have measured the performances of a LYSO crystal matrix prototype tested
with electron and photon beams in the energy range 60450 MeV. This study has
been carried out to determine the achievable energy and time resolutions for
the calorimeter of the Mu2e experiment.Comment: 2 pages, 3 figures, 13th Pisa Meeting on Advanced Detector
Crilin: A CRystal calorImeter with Longitudinal InformatioN for a future Muon Collider
The measurement of physics processes at new energy frontier experiments
requires excellent spatial, time, and energy resolutions to resolve the
structure of collimated high-energy jets. In a future Muon Collider, the
beam-induced backgrounds (BIB) represent the main challenge in the design of
the detectors and of the event reconstruction algorithms. The technology and
the design of the calorimeters should be chosen to reduce the effect of the
BIB, while keeping good physics performance. Several requirements can be
inferred: i) high granularity to reduce the overlap of BIB particles in the
same calorimeter cell; ii) excellent timing (of the order of 100 ps) to reduce
the out-of-time component of the BIB; iii) longitudinal segmentation to
distinguish the signal showers from the fake showers produced by the BIB; iv)
good energy resolution (less than 10%/sqrt(E)) to obtain good physics
performance, as has been already demonstrated for conceptual particle flow
calorimeters. Our proposal consists of a semi-homogeneous electromagnetic
calorimeter based on Lead Fluoride Crystals (PbF2) readout by surface-mount
UV-extended Silicon Photomultipliers (SiPMs): the Crilin calorimeter. In this
paper, the performances of the Crilin calorimeter in the Muon Collider
framework for hadron jets reconstruction have been analyzed. We report the
single components characterizations together with the development of a
small-scale prototype, consisting of 2 layers of 3x3 crystals each
Measurement of the front-end dead-time of the LHCb muon detector and evaluation of its contribution to the muon detection inefficiency
A method is described which allows to deduce the dead-time of the front-end
electronics of the LHCb muon detector from a series of measurements performed
at different luminosities at a bunch-crossing rate of 20 MHz. The measured
values of the dead-time range from 70 ns to 100 ns. These results allow to
estimate the performance of the muon detector at the future bunch-crossing rate
of 40 MHz and at higher luminosity
The Mu2e undoped CsI crystal calorimeter
The Mu2e experiment at Fermilab will search for Charged Lepton Flavor
Violating conversion of a muon to an electron in an atomic field. The Mu2e
detector is composed of a tracker, an electromagnetic calorimeter and an
external system, surrounding the solenoid, to veto cosmic rays. The calorimeter
plays an important role to provide: a) excellent particle identification
capabilities; b) a fast trigger filter; c) an easier tracker track
reconstruction. Two disks, located downstream of the tracker, contain 674 pure
CsI crystals each. Each crystal is read out by two arrays of UV-extended SiPMs.
The choice of the crystals and SiPMs has been finalized after a thorough test
campaign. A first small scale prototype consisting of 51 crystals and 102 SiPM
arrays has been exposed to an electron beam at the BTF (Beam Test Facility) in
Frascati. Although the readout electronics were not the final, results show
that the current design is able to meet the timing and energy resolution
required by the Mu2e experiment.Comment: 6 pages, 8 figures, proceedings of the "Calorimetry for the high
energy frontier (CHEF17)" conference, 2-6 October 2017, Lyon, Franc
Quality Assurance on a custom SiPMs array for the Mu2e experiment
The Mu2e experiment at Fermilab will search for the coherent
conversion on aluminum atoms. The detector system consists of a straw tube
tracker and a crystal calorimeter. A pre-production of 150 Silicon
Photomultiplier arrays for the Mu2e calorimeter has been procured. A detailed
quality assur- ance has been carried out on each SiPM for the determination of
its own operation voltage, gain, dark current and PDE. The measurement of the
mean-time-to-failure for a small random sample of the pro-production group has
been also completed as well as the determination of the dark current increase
as a function of the ioninizing and non-ioninizing dose.Comment: 4 pages, 10 figures, conference proceeding for NSS-MIC 201
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