Search results for "Instrument"
showing 10 items of 5652 documents
Estimates for Divergence Velocities of Axially Moving Orthotropic Thin Plates
2014
Some models for axially moving orthotropic thin plates are investigated analytically via methods of complex analysis to derive estimates for critical plate velocities. Linearised Kirchhoff plate theory is used, and the energy forms of steady-state models are considered with homogeneous and inhomogeneous tension profiles in the cross direction of the plate. With the help of the energy forms, some limits for the divergence velocity of the plate are found analytically. In numerical examples, the derived lower limits for the divergence velocity are analysed for plates with small flexural rigidity. peerReviewed
Search for Axionlike Dark Matter through Nuclear Spin Precession in Electric and Magnetic Fields
2017
We report on a search for ultralow-mass axionlike dark matter by analyzing the ratio of the spinprecession frequencies of stored ultracold neutrons and 199Hg atoms for an axion-induced oscillating electric dipole moment of the neutron and an axion-wind spin-precession effect. No signal consistent with dark matter is observed for the axion mass range 10−24 ≤ ma ≤ 10−17 eV. Our null result sets the first laboratory constraints on the coupling of axion dark matter to gluons, which improve on astrophysical limits by up to 3 orders of magnitude, and also improves on previous laboratory constraints on the axion coupling to nucleons by up to a factor of 40. ispartof: Physical Review X vol:7 issue:…
Conceptual design and simulation of a water Cherenkov muon veto for the XENON1T experiment
2014
XENON is a direct detection dark matter project, consisting of a time projection chamber (TPC) that uses xenon in double phase as a sensitive detection medium. XENON100, located at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, is one of the most sensitive experiments of its field. During the operation of XENON100, the design and construction of the next generation detector (of ton-scale mass) of the XENON project, XENON1T, is taking place. XENON1T is being installed at LNGS as well. It has the goal to reduce the background by two orders of magnitude compared to XENON100, aiming at a sensitivity of $2 \cdot 10^{-47} \mathrm{cm}^{\mathrm{2}}$ for a WIMP mass of 50 GeV/c$^{2}$. With…
Time-integrated Neutrino Source Searches with 10 years of IceCube Data
2020
Physical review letters 124(5), 051103 (1-9) (2020). doi:10.1103/PhysRevLett.124.051103
Neutrinos below 100 TeV from the southern sky employing refined veto techniques to IceCube data
2020
Many Galactic sources of gamma rays, such as supernova remnants, are expected to produce neutrinos with a typical energy cutoff well below 100 TeV. For the IceCube Neutrino Observatory located at the South Pole, the southern sky, containing the inner part of the Galactic plane and the Galactic Center, is a particularly challenging region at these energies, because of the large background of atmospheric muons. In this paper, we present recent advancements in data selection strategies for track-like muon neutrino events with energies below 100 TeV from the southern sky. The strategies utilize the outer detector regions as veto and features of the signal pattern to reduce the background of atm…
Comparison between simulated and observed LHC beam backgrounds in the ATLAS experiment at E beam =4 TeV
2018
Results of dedicated Monte Carlo simulations of beam-induced background (BIB) in the ATLAS experiment at the Large Hadron Collider (LHC) are presented and compared with data recorded in 2012. During normal physics operation this background arises mainly from scattering of the 4 TeV protons on residual gas in the beam pipe. Methods of reconstructing the BIB signals in the ATLAS detector, developed and implemented in the simulation chain based on the FLUKA Monte Carlo simulation package, are described. The interaction rates are determined from the residual gas pressure distribution in the LHC ring in order to set an absolute scale on the predicted rates of BIB so that they can be compared qua…
New high-sensitivity searches for neutrons converting into antineutrons and/or sterile neutrons at the HIBEAM/NNBAR experiment at the European Spalla…
2021
Abstract The violation of baryon number, B , is an essential ingredient for the preferential creation of matter over antimatter needed to account for the observed baryon asymmetry in the Universe. However, such a process has yet to be experimentally observed. The HIBEAM/NNBAR program is a proposed two-stage experiment at the European Spallation Source to search for baryon number violation. The program will include high-sensitivity searches for processes that violate baryon number by one or two units: free neutron–antineutron oscillation ( n → n ̄ ) via mixing, neutron–antineutron oscillation via regeneration from a sterile neutron state ( n → [ n ′ , n ̄ ′ ] → n ̄ ), and neutron disappearan…
Study of supersymmetric signals with R-parity violation in ATLAS at LHC
2013
219 páginas. Tesis Doctoral del Departamento de Física Atómica, Molecular y Nuclear, de la Universidad de Valencia.
Less Data Same Information for Event-Based Sensors: A Bioinspired Filtering and Data Reduction Algorithm
2018
Sensors provide data which need to be processed after acquisition to remove noise and extract relevant information. When the sensor is a network node and acquired data are to be transmitted to other nodes (e.g., through Ethernet), the amount of generated data from multiple nodes can overload the communication channel. The reduction of generated data implies the possibility of lower hardware requirements and less power consumption for the hardware devices. This work proposes a filtering algorithm (LDSI&mdash
Heat production of frogs under normoxic and hypoxic conditions: A microcalorimetric study using a gas flow system
1991
Abstract Heat production of male frogs, Rana temporaria , was measured in a microcalorimeter through which a continuous flow of gas was passed in order to generate constant normoxic, hypoxic or anoxic conditions. The normoxic heat flow was 163 ± 37 μ W g body weight in frogs that had not been treated with curare and 149 ± 69 μ W g in animals immobilized with curare. During anoxia, frogs, whether curarized or not, decreased their heat production to about 25% of the respective normoxic control. In graded hypoxia (10% to 3% O 2 ), curarized frogs decreased their heat rate according to the grade of hypoxia they were subjected to.