A new experiment, named WAGASCI can precisely measure the ratio of muon neutrino cross sections between water and hydrocarbon for charged-current interactions with a large angular acceptance at ...J-PARC. A new detector mainly consists of two water target modules and two hydrocarbon target modules. Each module is composed of scintillators aligned in a 3D grid-like structure having almost 4π solid angle acceptance. Each scintillator has a groove for a WLS fiber to be put on, and they are glued with the optical cement by using a semi-automated gluing system. WLS fibers are connected to Multi-Pixel Photon Counters (MPPCs), which are crosstalk suppression type. The detector is now under construction, and we will start taking the data in 2017.
The DeeMe experiment to search for muon-to-electron conversions with a sensitivity 10–100 times better than those achieved by previous experiments is in preparation at the Japan Proton Accelerator ...Research Complex. The magnetic spectrometer used by the DeeMe experiment consists of an electromagnet and four multiwire proportional chambers (MWPCs). The newly developed MWPCs are operated with a high voltage (HV) switching technique and have good burst-hit tolerance. In this article, the final designs of the MWPCs, amplifiers for readout, and HV switching modules are described. Additionally, some results of MWPC performance evaluation are presented.
High-energy physics experiments must usually handle large transfer rates of experimental data. In particular, in recent years, the amount and speed of data handled in high-energy physics experiments ...have significantly increased, because signal waveforms from detectors are often recorded without reduction to maximize the flexibility of the offline analysis. To best exploit the available bandwidth of such data acquisition systems with waveform recording, we developed the real-time lossless waveform-compression firmware that is based on a delta-encoding technique. The firmware provides a compression ratio of 34% of the raw data produced, the fast analog-to-digital converter (FADC) boards of our application before transmission to a host computer. The resource consumption of a field-programmable gate array (FPGA) is not large, and a low-cost mid-range FPGA is sufficient to implement this proposed firmware. The firmware has been successfully implemented on an FADC board and was utilized to record signals from multiwire proportional chambers for the DeeMe experiment. In this paper, we present the theory related to the firmware design and its implementation on the FPGA.
A new experiment, called DeeMe, which is designed to search for μ−e conversions with a sensitivity of O(10−14), is in preparation at the Japan Proton Accelerator Research Complex (J-PARC). It ...utilizes a high-quality pulsed proton beam from the Rapid Cycling Synchrotron at J-PARC. The detector for DeeMe must tolerate large pulses of prompt charged particles whose instantaneous hit rate is as large as 70 GHz mm−2 in a time width of 200 ns, and detect a single electron that arrives with delayed timing on the order of microseconds. A special wire chamber has been developed with a new dynamic gain control technique that reduces space charge effects. In this paper, we detail the novel detector scheme and operation verification.
Abstract
Precise neutrino–nucleus interaction measurements in the sub-multi-GeV region are important to reduce the systematic uncertainty in future neutrino oscillation experiments. Furthermore, an ...excess of
${\nu_e}$
interactions, as a possible interpretation of the existence of a sterile neutrino, has been observed in such an energy region. The nuclear emulsion technique can measure all the final state particles with low energy threshold for a variety of targets (Fe, C, H
${_2}$
O, and so on). Its sub-
$\mu$
m position resolution allows measurements of the
${\nu_e}$
cross-section with good electron/gamma separation capability. We started a new experiment at J-PARC to study sub-multi-GeV neutrino interactions by introducing the nuclear emulsion technique. The J-PARC T60 experiment has been implemented as a first step in such a project. Systematic neutrino event analysis with full scanning data in the nuclear emulsion detector was performed for the first time. The first neutrino event detection and its analysis are described in this paper.
Abstract
We describe the first ever implementation of a clock-based, multi-stage emulsion shifter in an accelerator neutrino experiment. The system was installed in the neutrino monitoring building ...at the Japan Proton Accelerator Research Complex as part of a test experiment, T60, and stable operation was maintained for a total of 126.6 days. By applying time information to emulsion films, various results were obtained. Time resolutions of 5.3–14.7 s were evaluated in an operation spanning 46.9 days (yielding division numbers of 1.4–3.8
$\times10^{5}$
). By using timing and spatial information, reconstruction of coincident events consisting of high-multiplicity and vertex-contained events, including neutrino events, was performed. Emulsion events were matched to events observed by INGRID, one of the on-axis near detectors of the T2K experiment, with high reliability (98.5%), and hybrid analysis of the emulsion and INGRID events was established by means of the multi-stage shifter. The results demonstrate that the multi-stage shifter can feasibly be used in neutrino experiments.
The T2K (Tokai-to-Kamioka) is a long baseline neutrino experiment designed to study various parameters that rule neutrino oscillations, with an intense beam of muon neutrinos. A near detector complex ...(ND280) is used to constrain non-oscillated flux and hence to predict the expected number of events in the far detector (Super-Kamiokande). The difference in the target material between the far (water) and near (scintillator, hydrocarbon) detectors leads to the main non-canceling systematic uncertainty for the oscillation analysis. In order to reduce this uncertainty a new water grid and scintillator detector, WAGASCI, has been proposed. The detector will be operated at the J-PARC neutrino beam line with the main physics goal to measure the charged current neutrino cross section ratio between water and hydrocarbon with a few percent accuracy. Further physics program may include high-precision measurements of different charged current neutrino interaction channels. The concept of the new detector will be covered together with the actual construction plan.
The CDF plug upgrade electromagnetic calorimeter: test beam results Albrow, M.; Aota, S.; Apollinari, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2002, Letnik:
480, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The CDF Plug Upgrade calorimeter, which fully exploits the tile–fiber technique, was tested at the Fermilab meson beamline. The calorimeter was exposed to positron, positively charged pion and ...positive muon beams with energies in the range of 5–
230
GeV
. The energy resolution of the electromagnetic calorimeter to the positron beam is consistent with the design value of
16%/
E
⊕1%
, where E is the energy in units of GeV and ⊕ represents sum in quadrature. The non-linearity for positrons is studied in an energy range of 11–
181
GeV
. It is important to incorporate the response of the preshower detector, the first layer of the electromagnetic calorimeter which is readout separately, into that of the calorimeter to reduce the non-linearity to 1% or less. The energy scale is about
1.46
pC/
GeV
with HAMAMATSU R4125 operated typically at a gain of 2.5×10
4. The response non-uniformity over the surface of a tower of the electromagnetic calorimeter is found to be about 2% with
57
GeV
positrons. Studies of several detailed detector characteristics are also presented.
Intercalibration of the longitudinal segments of a calorimeter system Albrow, M; Aota, S; Apollinari, G ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2002, Letnik:
487, Številka:
3
Journal Article
Recenzirano
Three different methods of setting the hadronic energy scale of a longitudinally segmented calorimeter system are compared with each other. The merits of these methods have been studied with testbeam ...data from the CDF Plug Upgrade Calorimeter. It turns out that one of the (commonly used) calibration methods introduces a number of undesirable side effects, such as an increased hadronic signal nonlinearity and trigger biases resulting from the fact that the reconstructed energy of hadrons depends on the starting point of their showers. These problems can be avoided when a different calibration method is used. The results of this study are applied to determine the
e/
h values of the calorimeter and its segments.