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Photoproduction de Mesons sur le Nucleon aux Energies Intermediaire (in French) [Photoproduction of mesons on the nucleon at intermediate energies] (in French)
Abstract
One object of this thesis is to propose a model taking account of low transfer reaction mechanisms for a series of photoproduction reactions on nucleons for photon energies ≳4 GeV. If our comprehension of processes with low transfers is correct, then extrapolating our model in the domain of large transfers and the comparison with data supplied will give us information on the domains in energy and transfers from which an interpretation of reactions in terms of the "soft" process ceases to be valid. In the domain of large transfers, only one approach in terms of "hard" process can then explain the data. We are interested in electromagnetic photoproduction reactions because the probe, firstly, interacts with the target via an exact and well known mechanism (described by the QED theory) and also eliminates the interaction phenomena in the initial state. No probe is as well known as the photon. The extraction of reaction mechanisms, amplitudes and coupling constants match is made easier than in the case of hadronic probes. The energy domain Eγ >4 GeV studied is particularly interesting because it is from this energy of incident photons that can be expected to achieve large enough pulse transfers to hope formore »
- Authors:
-
- Univ. of Paris, Orsay (France)
- Publication Date:
- Research Org.:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC)
- OSTI Identifier:
- 1087077
- Report Number(s):
- JLAB-PHY-96-1; DOE/ER/40150-4971
- DOE Contract Number:
- AC05-84ER40150
- Resource Type:
- Thesis/Dissertation
- Country of Publication:
- United States
- Language:
- French
- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Citation Formats
Guidal, Michel. Photoproduction de Mesons sur le Nucleon aux Energies Intermediaire (in French) [Photoproduction of mesons on the nucleon at intermediate energies]. United States: N. p., 1996.
Web. doi:10.2172/1087077.
Guidal, Michel. Photoproduction de Mesons sur le Nucleon aux Energies Intermediaire (in French) [Photoproduction of mesons on the nucleon at intermediate energies]. United States. https://doi.org/10.2172/1087077
Guidal, Michel. 1996.
"Photoproduction de Mesons sur le Nucleon aux Energies Intermediaire (in French) [Photoproduction of mesons on the nucleon at intermediate energies]". United States. https://doi.org/10.2172/1087077. https://www.osti.gov/servlets/purl/1087077.
@article{osti_1087077,
title = {Photoproduction de Mesons sur le Nucleon aux Energies Intermediaire (in French) [Photoproduction of mesons on the nucleon at intermediate energies]},
author = {Guidal, Michel},
abstractNote = {One object of this thesis is to propose a model taking account of low transfer reaction mechanisms for a series of photoproduction reactions on nucleons for photon energies ≳4 GeV. If our comprehension of processes with low transfers is correct, then extrapolating our model in the domain of large transfers and the comparison with data supplied will give us information on the domains in energy and transfers from which an interpretation of reactions in terms of the "soft" process ceases to be valid. In the domain of large transfers, only one approach in terms of "hard" process can then explain the data. We are interested in electromagnetic photoproduction reactions because the probe, firstly, interacts with the target via an exact and well known mechanism (described by the QED theory) and also eliminates the interaction phenomena in the initial state. No probe is as well known as the photon. The extraction of reaction mechanisms, amplitudes and coupling constants match is made easier than in the case of hadronic probes. The energy domain Eγ >4 GeV studied is particularly interesting because it is from this energy of incident photons that can be expected to achieve large enough pulse transfers to hope for emergence of hard processes and therefore see the cessation of validity of interpretation of hadron models. Also, resonance effects are minor and do not interfere with our interpretations. Experimentally, this area is widely unexplored and the new generation accelerators of a large duty cycle (CEBAF, MAMI, ESRF, ELF, ...) combined with 4π detectors will allow to precisely measure low cross sections reactions of a large transfer. We first study pion photoproduction reactions on nucleon because they are the most experimentally accessible reactions and many data of high energy and low transfers exist. This will require strong constraints on the model parameters of the numerous analyses performed previously. Then we'll move on to kaon photoproduction reactions and φ because, as will be developed further, the strangeness constitutes privileged probe to investigate the hard processes. Our survey is interested in reactions on nucleons because it is necessary to understand well the elementary mechanisms before studying nuclei (effects of medium, Hypernuclei, color transparency effects, ...). This thesis is divided into two main parts. The first is essentially theoretical and we will discuss the ideas, formalism of calculation and outcomes of our model. The second is more experimental and we present simulations and studies done to demonstrate the feasibility of the experiments we propose to put in evidence hard mechanisms using the CLAS detector at CEBAF.},
doi = {10.2172/1087077},
url = {https://www.osti.gov/biblio/1087077},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Dec 13 00:00:00 EST 1996},
month = {Fri Dec 13 00:00:00 EST 1996}
}