scholarly journals Bilocal field theory and a model for meson spectroscopy. Part I. Trident production by high energy charged particles on nuclei. Part II. [Harmonic oscillator quark model, radiative corrections, cross sections covariant perturbation theory, interference]

1979 ◽  
Author(s):  
K. Mita
Keyword(s):  
Field Theory ◽  
Perturbation Theory ◽  
Harmonic Oscillator ◽  
Quark Model ◽  
Cross Sections ◽  
Charged Particles ◽  
High Energy ◽  
Radiative Corrections ◽  
Meson Spectroscopy ◽  
Bilocal Field

scholarly journals MARINARI–PARISI AND SUPERSYMMETRIC COLLECTIVE FIELD THEORY

1993 ◽  
Vol 08 (15) ◽  
pp. 2517-2550 ◽  
Author(s):  
JOÃO P. RODRIGUES ◽  
ANDRÉ J. VAN TONDER
Keyword(s):  
Field Theory ◽  
Perturbation Theory ◽  
Harmonic Oscillator ◽  
String Field Theory ◽  
Continuum Limit ◽  
Infinite Sequence ◽  
Majorana Fermion ◽  
Oscillator Basis ◽  
Continuum Description ◽  
Massless Boson

A field theoretic formulation of the Marinari–Parisi supersymmetric matrix model is established and shown to be equivalent to a recently proposed supersymmetrization of the bosonic collective string field theory. It also corresponds to a continuum description of super-Calogero models. The perturbation theory of the model is developed and, in this approach, an infinite sequence of vertices is generated. A class of potentials is identified for which the spectrum is that of a massless boson and Majorana fermion. For the harmonic oscillator case, the cubic vertices are obtained in an oscillator basis. For a rather general class of potentials it is argued that one cannot generate from Marinari–Parisi models a continuum limit similar to that of the d = 1 bosonic string.

scholarly journals Elastic scattering and diffractive dissociation in the light of LHC data

2015 ◽  
Vol 30 (08) ◽  
pp. 1542004 ◽  
Author(s):  
V. A. Khoze ◽  
A. D. Martin ◽  
M. G. Ryskin
Keyword(s):  
Field Theory ◽  
Cross Sections ◽  
Hadron Collider ◽  
High Energy ◽  
Momentum Dependence ◽  
Diffractive Dissociation ◽  
Proton Dissociation ◽  
Diffractive Data ◽  
Rapidity Dependence ◽  
Reggeon Field Theory

We study the behavior of elastic and diffractive proton dissociation cross sections at high energy. First, we describe what would be expected to be observed at the Large Hadron Collider (LHC) based on conventional Regge theory. We emphasize the tension between these expectations and the recent LHC measurements, and we discuss the possibilty to modify the classic Reggeon Field Theory (RFT) in a physically-motivated way so as to accommodate the tendencies observed at the LHC. As a result, we show that we are able to achieve a "global" description of the wide variety of high energy elastic and diffractive data that are presently available, particularly from the LHC experiments. The model is based on only one pomeron pole, but includes multi-pomeron interactions and, significantly, includes the transverse momentum dependence of intermediate partons as a function of their rapidity, which provides the rapidity dependence of the multi-pomeron vertices. We give predictions for diffractive observables at LHC, and higher, energies.

scholarly journals Production of heavy charged particles in proton-proton ultraperipheral collisions at the Large Hadron Collider: survival factor

2021 ◽  
Vol 2021 (10) ◽  
Author(s):  
S. I. Godunov ◽  
V. A. Novikov ◽  
A. N. Rozanov ◽  
M. I. Vysotsky ◽  
E. V. Zhemchugov
Keyword(s):  
Large Hadron Collider ◽  
Cross Sections ◽  
Hadron Collider ◽  
Charged Particles ◽  
High Energy ◽  
Proton Proton ◽  
Heavy Charged Particles ◽  
Survival Factors ◽  
Survival Factor

Abstract Ultraperipheral collisions of high energy protons are a source of approximately real photons colliding with each other. Photon fusion can result in production of yet unknown charged particles in very clean events. The cleanliness of such an event is due to the requirement that the protons survive during the collision. Finite sizes of the protons reduce the probability of such outcome compared to point-like particles. We calculate the survival factors and cross sections for the production of heavy charged particles at the Large Hadron Collider.

scholarly journals Measuring the Impact of Nuclear Interaction in Particle Therapy and in Radio Protection in Space: the FOOT Experiment

2021 ◽  
Vol 8 ◽  
Author(s):  
Giuseppe Battistoni ◽  
Marco Toppi ◽  
Vincenzo Patera ◽  
The FOOT Collaboration
Keyword(s):  
Cross Sections ◽  
Computational Models ◽  
Bragg Peak ◽  
Charged Particles ◽  
Absorbed Dose ◽  
High Energy ◽  
Particle Therapy ◽  
Main Concern ◽  
Nuclear Fragmentation ◽  
The Impact

In Charged Particle Therapy (PT) proton or 12C beams are used to treat deep-seated solid tumors exploiting the advantageous characteristics of charged particles energy deposition in matter. For such projectiles, the maximum of the dose is released at the end of the beam range, in the Bragg peak region, where the tumour is located. However, the nuclear interactions of the beam nuclei with the patient tissues can induce the fragmentation of projectiles and/or target nuclei and needs to be carefully taken into account when planning the treatment. In proton treatments, the target fragmentation produces low energy, short range fragments along all the beam path, that deposit a non-negligible dose especially in the first crossed tissues. On the other hand, in treatments performed using 12C, or other (4He or 16O) ions of interest, the main concern is related to the production of long range fragments that can release their dose in the healthy tissues beyond the Bragg peak. Understanding nuclear fragmentation processes is of interest also for radiation protection in human space flight applications, in view of deep space missions. In particular 4He and high-energy charged particles, mainly 12C, 16O, 28Si and 56Fe, provide the main source of absorbed dose in astronauts outside the atmosphere. The nuclear fragmentation properties of the materials used to build the spacecrafts need to be known with high accuracy in order to optimise the shielding against the space radiation. The study of the impact of these processes, which is of interest both for PT and space radioprotection applications, suffers at present from the limited experimental precision achieved on the relevant nuclear cross sections that compromise the reliability of the available computational models. The FOOT (FragmentatiOn Of Target) collaboration, composed of researchers from France, Germany, Italy and Japan, designed an experiment to study these nuclear processes and measure the corresponding fragmentation cross sections. In this work we discuss the physics motivations of FOOT, describing in detail the present detector design and the expected performances, coming from the optimization studies based on accurate FLUKA MC simulations and preliminary beam test results. The measurements planned will be also presented.

scholarly journals FERMIONS IN THE INSTANTON-ANTI-INSTANTON VALLEY AND HIGH-ENERGY ELECTROWEAK INTERACTIONS

1994 ◽  
Vol 09 (15) ◽  
pp. 2613-2644
Author(s):  
RICCARDO GUIDA ◽  
KENICHI KONISHI
Keyword(s):  
Perturbation Theory ◽  
Correlation Function ◽  
Dirac Operator ◽  
Cross Sections ◽  
Theoretical Basis ◽  
High Energy ◽  
Electroweak Theory ◽  
Electroweak Interactions ◽  
Fermion Number ◽  
Chern Simons

We consider the behavior of fermions in the background of instanton-anti-instanton valley fields. Several different physics problems, from the high-energy electroweak interactions to the study of vacuum structure of QCD and of large orders of perturbation theory, are related to this problem. The spectrum of the Dirac operator in such a background is studied in detail. We present an approximation for the fermion correlation function when the instanton-anti-instanton separation (R) is large compared to their sizes (ρ). The situation where the instanton-anti-instanton overlap and melt is studied through the behavior of the Chern-Simons number as a function of R/ρ and x4. Applying our results to widely discussed cases of fermion-number violation in the electroweak theory, we conclude that there is no theoretical basis for expecting anomalous cross-sections to become observable at energies in the 10 TeV region.

scholarly journals The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles

1995 ◽  
Vol 28 (6) ◽  
pp. 913-940 ◽  
Author(s):  
J H McGuire ◽  
N Berrah ◽  
R J Bartlett ◽  
J A R Samson ◽  
J A Tanis ◽  
...  
Keyword(s):  
Cross Sections ◽  
Charged Particles ◽  
High Energy ◽  
Single Ionization

scholarly journals On Finite-Temperature and Finite-Density Radiative Corrections to the Neutrino Effective Potential in the Early Universe

1997 ◽  
Vol 12 (32) ◽  
pp. 2461-2468
Author(s):  
R. Horvat
Keyword(s):  
Field Theory ◽  
Perturbation Theory ◽  
Early Universe ◽  
Effective Potential ◽  
Finite Temperature ◽  
Thermal Field ◽  
Radiative Corrections ◽  
Symmetric Part ◽  
Finite Density ◽  
Nonzero Contribution

Finite-temperature and finite-density radiative corrections to the neutrino effective potential in the otherwise CP-symmetric early Universe are considered in the real-time approach of thermal field theory. A consistent perturbation theory endowed with the hard thermal loop resummation techniques developed by Braaten and Pisarski is applied. Special attention is focused on the question whether such corrections can generate any nonzero contribution to the CP-symmetric part of the neutrino potential, if the contact approximation for the W-propagator is used.

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