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Search for excited leptons in the next generation of experiments. [Preons]

Description: Production cross sections of excited leptons in e/sup +/e/sup -/ annihilation experiments are estimated. Light excited states can be produced below the characteristic energy scale at which hypothetical constituents of leptons become bound: therefore the estimates are expected to be valid for E/sub cm/ less than or equal to 100 GeV, and to a large degree, model independent. The results are expressed in terms of measurable low energy parameters. It is concluded that high precision experiments are needed for an effective search for excited leptons.
Date: September 1, 1981
Creator: Domokos, G. & Koevesi-Domokos, S.
Partner: UNT Libraries Government Documents Department

Research in theoretical physics

Description: In this report we describe a research undertaken approximately three years ago: in it we investigate possible signatures of physics non described by the Standard Model of electroweak and strong interactions. The source of such data is signals obtained from observations of point sources in the sky, typically x-ray binary stars, but also some others, such as the CRAB nebula.
Date: October 1, 1990
Creator: Domokos, G. & Kovesi-Domokos, S.
Partner: UNT Libraries Government Documents Department

Direct effect of diagnostic ultrasound on genetically interesting molecules

Description: Ultrasound is a non-ionizing radiation and at typical intensities used in diagnostic sonography, macroscopic damage to tissues is negligible. Some recent experiments, however, provided evidence for possible genetic damage caused by relatively low-intensity ultrasound irradiation. Although the implications of such experiments concerning possible genetic damage caused by low intensity ultrasound irradiation are not yet completely understood, the very existence of such results raises an important theoretical question. Is it possible that a non-ionizing radiation can cause significant changes in the structure of a typical DNA molecule. Several mechanisms exist which are responsible for such changes including: (1) structural changes in the molecule due to sound absorption from a high harmonic of the repetition frequency of a pulsed ultrasound radiation; (2) structural changes due to multi-phonon absorption from low harmonics of the repetition frequency; and (3) break-up of the molecule as a consequence of the excitation of collective vibrations. The calculations presented suggest that, should damage to DNA in vitro caused by low-intensity ultrasound be confirmed beyond reasonable doubt, such catastrophic changes in the structure of DNA molecules are more likely to arise as a result of their collective modes rather than from a localizable breakup of some hydrogen bonds. (ERB)
Date: January 1, 1981
Creator: Ciatti, S.; Domokos, G.; Koevesi-Domokos, S. & Milano, F.
Partner: UNT Libraries Government Documents Department

Research in theoretical physics

Description: We propose the continuation of the research under this grant. We propose to extend the search for signatures of new physics'' to new processes. In particular, we want to investigate extensions of the search to hadronic reactions. The appearance of anomalous terms in the matrix elements of SU(3){sub color} currents, indicating the presence of new physics'' in the quark sector of the Standard Model, can be studied by following the jet evolution and hadronization. The effect is expected to be rather large in top quark initial state gluon Bremsstrahlung, thus colliders are a good testing ground for the presence of new physics'' even at Tevatron energies. We continue the study of astro-particle physics. We propose to investigate further the structure of extensive air showers associated with point sources in the sky. We propose to study neutrino production in the Milky Way: this will enable us both to estimate the background of neutrino telescopes and to search for the presence of baryonic dark matter in the galactic halo.
Date: November 1, 1991
Creator: Domokos, G. & Kovesi-Domokos, S.
Partner: UNT Libraries Government Documents Department

Research in theoretical physics. [Henry A. Rowland Dept. of Physics and Astronomy, The Johns Hopkins Univ. , Baltimore, Maryland]

Description: Progress made in the following areas is summarized: simulation of extensive air showers induced by interactions existing beyond the currently accepted Standard Model'' of elementary particle interactions; search for physics beyond the Standard Model'' in gluonic inclusive decays of heavy quarks; obtaining limits on the applicability of the special theory of relativity; an improved method of obtaining upper limits on the masses of primaries of extensive air showers associated with point sources in the sky. 8 figs., 1 tab., 73 refs.
Date: December 1, 1992
Creator: Domokos, G. & Kovesi-Domokos, S.
Partner: UNT Libraries Government Documents Department

Research in theoretical physics. Annual Progress report, April 1, 1991--March 31, 1992

Description: We propose the continuation of the research under this grant. We propose to extend the search for signatures of ``new physics`` to new processes. In particular, we want to investigate extensions of the search to hadronic reactions. The appearance of anomalous terms in the matrix elements of SU(3){sub color} currents, indicating the presence of ``new physics`` in the quark sector of the Standard Model, can be studied by following the jet evolution and hadronization. The effect is expected to be rather large in top quark initial state gluon Bremsstrahlung, thus colliders are a good testing ground for the presence of ``new physics`` even at Tevatron energies. We continue the study of astro-particle physics. We propose to investigate further the structure of extensive air showers associated with point sources in the sky. We propose to study neutrino production in the Milky Way: this will enable us both to estimate the background of neutrino telescopes and to search for the presence of baryonic dark matter in the galactic halo.
Date: November 1, 1991
Creator: Domokos, G. & Kovesi-Domokos, S.
Partner: UNT Libraries Government Documents Department

Research in theoretical physics. Final report

Description: This report summarizes the research carried out under Grant DE-FG02-85ER40211. The main topics covered are: astroparticle physics at very high and ultrahigh energies; search for new physics by means of detectors of ultrahigh energy particles of extraterrestrial origin. Methods for searching in heavy quark decays for signatures of physics beyond the standard model are developed.
Date: June 1, 1998
Creator: Domokos, G. & Kovesi-Domokos, S.
Partner: UNT Libraries Government Documents Department