2,722 research outputs found
Divisibility and primality in random walks
In this paper we study the divisibility and primality properties of the
Bernoulli random walk. We improve or extend some of our divisibility results to
wide classes of iid or independent non iid random walks. We also obtain new
primality results for the Rademacher random walk. We study the value
distribution of divisors of the random walk in the Cram\'er model, and obtain a
general estimate of a similar kind to that of the Bernouilli model. Earlier
results on divisors and quasi-prime numbers in the Bernoulli model are
recorded, as well as some other recent for the Cram\'er random model, based on
an estimate due to Selberg.Comment: 38 page
On Mukhin's necessary and sufficient condition for the validity of the local limit theorem
Mukhin found in 1984 an important necessary and sufficient condition for the
validity of the local limit theorem. Revisiting the succint proof given in
\cite{Mu2}, we could only prove rigorously a weaker necessary and sufficient
condition, with a significantly different formulation. This is the object of
this short Note.Comment: 4 pages. arXiv admin note: substantial text overlap with
arXiv:2208.0270
Deep Neural Networks for Energy and Position Reconstruction in EXO-200
We apply deep neural networks (DNN) to data from the EXO-200 experiment. In
the studied cases, the DNN is able to reconstruct the relevant parameters -
total energy and position - directly from raw digitized waveforms, with minimal
exceptions. For the first time, the developed algorithms are evaluated on real
detector calibration data. The accuracy of reconstruction either reaches or
exceeds what was achieved by the conventional approaches developed by EXO-200
over the course of the experiment. Most existing DNN approaches to event
reconstruction and classification in particle physics are trained on Monte
Carlo simulated events. Such algorithms are inherently limited by the accuracy
of the simulation. We describe a unique approach that, in an experiment such as
EXO-200, allows to successfully perform certain reconstruction and analysis
tasks by training the network on waveforms from experimental data, either
reducing or eliminating the reliance on the Monte Carlo.Comment: Accepted version. 33 pages, 28 figure
Search for nucleon decays with EXO-200
A search for instability of nucleons bound in Xe nuclei is reported
with 223 kgyr exposure of Xe in the EXO-200 experiment. Lifetime
limits of 3.3 and 1.9 yrs are established for
nucleon decay to Sb and Te, respectively. These are the most
stringent to date, exceeding the prior decay limits by a factor of 9 and 7,
respectively
Measurement of the Spectral Shape of the beta-decay of 137Xe to the Ground State of 137Cs in EXO-200 and Comparison with Theory
We report on a comparison between the theoretically predicted and
experimentally measured spectra of the first-forbidden non-unique -decay
transition ^{137}\textrm{Xe}(7/2^-)\to\,^{137}\textrm{Cs}(7/2^+). The
experimental data were acquired by the EXO-200 experiment during a deployment
of an AmBe neutron source. The ultra-low background environment of EXO-200,
together with dedicated source deployment and analysis procedures, allowed for
collection of a pure sample of the decays, with an estimated
signal-to-background ratio of more than 99-to-1 in the energy range from 1075
to 4175 keV. In addition to providing a rare and accurate measurement of the
first-forbidden non-unique -decay shape, this work constitutes a novel
test of the calculated electron spectral shapes in the context of the reactor
antineutrino anomaly and spectral bump.Comment: Version as accepted by PR
Sensitivity and discovery potential of the proposed nEXO experiment to neutrinoless double beta decay
The next-generation Enriched Xenon Observatory (nEXO) is a proposed
experiment to search for neutrinoless double beta () decay in
Xe with a target half-life sensitivity of approximately years
using kg of isotopically enriched liquid-xenon in a time
projection chamber. This improvement of two orders of magnitude in sensitivity
over current limits is obtained by a significant increase of the Xe
mass, the monolithic and homogeneous configuration of the active medium, and
the multi-parameter measurements of the interactions enabled by the time
projection chamber. The detector concept and anticipated performance are
presented based upon demonstrated realizable background rates.Comment: v2 as publishe
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