183 research outputs found
DANSSino: a pilot version of the DANSS neutrino detector
DANSSino is a reduced pilot version of a solid-state detector of reactor
antineutrinos (to be created within the DANSS project and installed under the
industrial 3 GW(th) reactor of the Kalinin Nuclear Power Plant -- KNPP).
Numerous tests performed at a distance of 11 m from the reactor core
demonstrate operability of the chosen design and reveal the main sources of the
background. In spite of its small size (20x20x100 ccm), the pilot detector
turned out to be quite sensitive to reactor antineutrinos, detecting about 70
IBD events per day with the signal-to-background ratio about unity.Comment: 16 pages, 11 figures, 3 tables. arXiv admin note: substantial text
overlap with arXiv:1304.369
Search for sterile neutrinos at the DANSS experiment
DANSS is a highly segmented 1~m plastic scintillator detector. Its 2500
one meter long scintillator strips have a Gd-loaded reflective cover. The DANSS
detector is placed under an industrial 3.1~ reactor of the
Kalinin Nuclear Power Plant 350~km NW from Moscow. The distance to the core is
varied on-line from 10.7~m to 12.7~m. The reactor building provides about 50~m
water-equivalent shielding against the cosmic background. DANSS detects almost
5000 per day at the closest position with the cosmic
background less than 3. The inverse beta decay process is used to detect
. Sterile neutrinos are searched for assuming the model
(3 active and 1 sterile ). The exclusion area in the plane is obtained using a ratio of positron energy
spectra collected at different distances. Therefore results do not depend on
the shape and normalization of the reactor spectrum, as well
as on the detector efficiency. Results are based on 966 thousand antineutrino
events collected at 3 distances from the reactor core. The excluded area covers
a wide range of the sterile neutrino parameters up to
in the most sensitive region.Comment: 10 pages, 13 figures, version accepted for publicatio
Pion and proton showers in the CALICE scintillator-steel analogue hadron calorimeter
Showers produced by positive hadrons in the highly granular CALICE
scintillator-steel analogue hadron calorimeter were studied. The experimental
data were collected at CERN and FNAL for single particles with initial momenta
from 10 to 80 GeV/c. The calorimeter response and resolution and spatial
characteristics of shower development for proton- and pion-induced showers for
test beam data and simulations using Geant4 version 9.6 are compared.Comment: 26 pages, 16 figures, JINST style, changes in the author list, typos
corrected, new section added, figures regrouped. Accepted for publication in
JINS
Hadron shower decomposition in the highly granular CALICE analogue hadron calorimeter
The spatial development of hadronic showers in the CALICE scintillator-steel
analogue hadron calorimeter is studied using test beam data collected at CERN
and FNAL for single positive pions and protons with initial momenta in the
range from 10 to 80 GeV/c. Both longitudinal and radial development of hadron
showers are parametrised with two-component functions. The parametrisation is
fit to test beam data and simulations using the QGSP_BERT and FTFP_BERT physics
lists from Geant4 version 9.6. The parameters extracted from data and simulated
samples are compared for the two types of hadrons. The response to pions and
the ratio of the non-electromagnetic to the electromagnetic calorimeter
response, h/e, are estimated using the extrapolation and decomposition of the
longitudinal profiles.Comment: 38 pages, 19 figures, 5 tables; author list changed; submitted to
JINS
Shower development of particles with momenta from 15 GeV to 150 GeV in the CALICE scintillator-tungsten hadronic calorimeter
We present a study of showers initiated by electrons, pions, kaons, and
protons with momenta from 15 GeV to 150 GeV in the highly granular CALICE
scintillator-tungsten analogue hadronic calorimeter. The data were recorded at
the CERN Super Proton Synchrotron in 2011. The analysis includes measurements
of the calorimeter response to each particle type as well as measurements of
the energy resolution and studies of the longitudinal and radial shower
development for selected particles. The results are compared to Geant4
simulations (version 9.6.p02). In the study of the energy resolution we include
previously published data with beam momenta from 1 GeV to 10 GeV recorded at
the CERN Proton Synchrotron in 2010.Comment: 35 pages, 21 figures, 8 table
Performance of the first prototype of the CALICE scintillator strip electromagnetic calorimeter
A first prototype of a scintillator strip-based electromagnetic calorimeter
was built, consisting of 26 layers of tungsten absorber plates interleaved with
planes of 45x10x3 mm3 plastic scintillator strips. Data were collected using a
positron test beam at DESY with momenta between 1 and 6 GeV/c. The prototype's
performance is presented in terms of the linearity and resolution of the energy
measurement. These results represent an important milestone in the development
of highly granular calorimeters using scintillator strip technology. This
technology is being developed for a future linear collider experiment, aiming
at the precise measurement of jet energies using particle flow techniques
The Time Structure of Hadronic Showers in highly granular Calorimeters with Tungsten and Steel Absorbers
The intrinsic time structure of hadronic showers influences the timing
capability and the required integration time of hadronic calorimeters in
particle physics experiments, and depends on the active medium and on the
absorber of the calorimeter. With the CALICE T3B experiment, a setup of 15
small plastic scintillator tiles read out with Silicon Photomultipliers, the
time structure of showers is measured on a statistical basis with high spatial
and temporal resolution in sampling calorimeters with tungsten and steel
absorbers. The results are compared to GEANT4 (version 9.4 patch 03)
simulations with different hadronic physics models. These comparisons
demonstrate the importance of using high precision treatment of low-energy
neutrons for tungsten absorbers, while an overall good agreement between data
and simulations for all considered models is observed for steel.Comment: 24 pages including author list, 9 figures, published in JINS
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