Analytic Calculation of the Atom Counting Statistics for the One-Atom Maser

We present an analytic calculation of the paramagnetic and diamagnetic contributions to the one-loop effective action in the SU(2) Higgs model. The paramagnetic contribution is produced by the gauge boson, while the diamagnetic contribution is produced by the gauge boson and the ghost. In the limit, where these particles are massless, the standard result of - 12 for the ratio of the paramagnetic to the diamagnetic contribution is reproduced. If the mass of the gauge boson and the ghost become much larger than the inverse vacuum correlation lengths of the Yang–Mills vacuum, the value of the ratio goes to - 8 . We also find that the same values of the ratio are achieved in the deconfinement phase of the model, up to the temperatures at which the dimensional reduction occurs.

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Probing the Eigenstates Thermalization Hypothesis with Many-Particle Quantum Walks on Lattices

Open Systems & Information Dynamics ◽

10.1142/s123016121750007x ◽

2017 ◽

Vol 24 (02) ◽

pp. 1750007

Author(s):

Dibwe Pierrot Musumbu ◽

Maria Przybylska ◽

Andrzej J. Maciejewski

Keyword(s):

Thermal State ◽

Particle System ◽

Hamiltonian Dynamics ◽

Quantum Walk ◽

Quantum Walks ◽

Grid Graphs ◽

Time Quantum ◽

Counting Statistics ◽

The Many ◽

The One

We simulate the dynamics of many-particle system of bosons and fermions using discrete time quantum walks on lattices. We present a computational proof of the behaviour of the simulated systems similar to the one observed in Hamiltonian dynamics during quantum thermalization. We record the time evolution of the entropy and the temperature of a specific particle configuration during the entire dynamics and observe how they relax to a state which we call the quantum walk thermal state. This observation is made on two types of lattices while simulating different numbers of particles walking on two grid graphs with 25 vertices. In each case, we observe that the vertices counting statistics, the temperature of the indexed configuration and the dimension of the effective configuration Hilbert space relax simultaneously and remain relaxed for the rest of the many-particle quantum walk.

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From the sinh-Gordon field theory to the one-dimensional Bose gas: exact local correlations and full counting statistics

Journal of Statistical Mechanics Theory and Experiment ◽

10.1088/1742-5468/aaeb48 ◽

2018 ◽

Vol 2018 (11) ◽

pp. 113104 ◽

Cited By ~ 22

Author(s):

Alvise Bastianello ◽

Lorenzo Piroli

Keyword(s):

Field Theory ◽

Bose Gas ◽

One Dimensional ◽

Full Counting Statistics ◽

Local Correlations ◽

Counting Statistics ◽

The One

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Detector Dead Time Determination and Optimal Counting Rate for a Detector Near a Spallation Source or a Subcritical Multiplying System

Science and Technology of Nuclear Installations ◽

10.1155/2012/240693 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

V. Bécares ◽

J. Blázquez

Keyword(s):

Counting Rate ◽

Dead Time ◽

Simple Expression ◽

Optimal Position ◽

Spallation Source ◽

Time Determination ◽

Accelerator Driven Systems ◽

Counting Statistics ◽

The One

The operation of accelerator-driven systems or spallation sources requires the monitoring of intense neutron fluxes, which may be billions-fold more intense than the fluxes obtained with usual radioactive sources. If a neutron detector is placed near a very intense source, it can become saturated because of detector dead time. On the contrary, if it is placed far away from the source, it will lose counting statistics. For this reason, there must exist an optimal position for placing the detector. The optimal position is defined as the one with the minimal relative uncertainty in the counting rate. In this work, we review the techniques to determine the detector dead time that can be applied with an accelerator-driven subcritical system or a spallation source. For the case of a spallation source, counting rates do not follow Poisson's statistics because of the multiplicity of the number of neutrons emitted by incident proton. It has been found a simple expression that relates the optimal counting rate with the source multiplicity and the uncertainty in the determination of the dead time.

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Exact thermal properties of free-fermionic spin chains

SciPost Physics ◽

10.21468/scipostphys.11.1.013 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Michał Białończyk ◽

Fernando Gómez-Ruiz ◽

Adolfo del Campo

Keyword(s):

Algebraic Approach ◽

Transverse Field ◽

Spin Chains ◽

One Dimensional ◽

Thermal Distribution ◽

Full Counting Statistics ◽

Integrable Spin ◽

Counting Statistics ◽

Integrable Spin Chains ◽

The One

An exact description of integrable spin chains at finite temperature is provided using an elementary algebraic approach in the complete Hilbert space of the system. We focus on spin chain models that admit a description in terms of free fermions, including paradigmatic examples such as the one-dimensional transverse-field quantum Ising and XY models. The exact partition function is derived and compared with the ubiquitous approximation in which only the positive parity sector of the energy spectrum is considered. Errors stemming from this approximation are identified in the neighborhood of the critical point at low temperatures. We further provide the full counting statistics of a wide class of observables at thermal equilibrium and characterize in detail the thermal distribution of the kink number and transverse magnetization in the transverse-field quantum Ising chain.

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