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Full-Text Articles in Physics
Ion Contribution To The Astrophysical Important 447.15, 587.56 And 667.82 Nm He I Spectral Lines Broadening, Vladimir Milosavljevic, Stevan Djenize
Ion Contribution To The Astrophysical Important 447.15, 587.56 And 667.82 Nm He I Spectral Lines Broadening, Vladimir Milosavljevic, Stevan Djenize
Articles
Characteristics of the astrophysical important Stark broadened 447.15 nm, 587.56 nm and 667.82 nm spectral line profiles have been measured at electron densities between 0.3 10 and 8.2 10 m and electron temperatures between 8000 and 33 000 K in plasmas created in five various discharge conditions using a linear, low-pressure, pulsed arc as an optically thin plasma source operated in a helium-nitrogen-oxygen gas mixture. On the basis of the observed asymmetry of the line profiles we have obtained their ion broadening parameters ( A) caused by influence of the ion microfield on the line broadening mechanism and also …
Measurement Of Parity-Nonconserving Rotation Of Neutron Spin In The 0.734-Ev P-Wave Resonance Of La-139, T. Haseyama, K. Asahi, J. D. Bowman, P. P. J. Delheij, H. Funahashi, S. Ishimoto, Gordon L. Jones, A. Masaike, Y. Masuda, Y. Matsuda, K. Morimoto, S. Muto, S. I. Penttila, V. R. Pomeroy, K. Sakai, E. I. Sharapov, D. A. Smith, V. W. Yuan
Measurement Of Parity-Nonconserving Rotation Of Neutron Spin In The 0.734-Ev P-Wave Resonance Of La-139, T. Haseyama, K. Asahi, J. D. Bowman, P. P. J. Delheij, H. Funahashi, S. Ishimoto, Gordon L. Jones, A. Masaike, Y. Masuda, Y. Matsuda, K. Morimoto, S. Muto, S. I. Penttila, V. R. Pomeroy, K. Sakai, E. I. Sharapov, D. A. Smith, V. W. Yuan
Articles
The parity nonconserving spin rotation of neutrons in the 0.734-eV p-wave resonance of La-139 was measured with the neutron transmission method. Two optically polarized He-3 cells were used before and behind a 5-cm long La-139 target, each as a polarizer and an analyzer for neutron spin. The rotation angle was carefully measured by flipping the direction of He-3 polarization in the polarizer in sequence. The peak-to-peak value of the spin rotation was determined to be (7.4+/-1.1) x 10(-3) rad/cm. The result is found to be consistent with the previous experiments, but the result was statistically improved. The s-p mixing model …
Stark Shifts And Transition Probabilities In The Ne Ii Spectrum, Stevan Djenize, Vladimir Milosavljevic, Milan S. Dimitrijevic
Stark Shifts And Transition Probabilities In The Ne Ii Spectrum, Stevan Djenize, Vladimir Milosavljevic, Milan S. Dimitrijevic
Articles
Stark shifts (d) and transition probabilities of the spontaneous emission (Einstein's A values) of forty two singly charged neon ( ) ion spectral lines have been measured in a linear, low pressure, pulsed arc at 35 300 K electron temperature and 1.83 10 23 m -3 electron density. Transition probabilities have been obtained using the relative line intensity ratio (RLIR) method. Stark shift values have also been calculated, using the semiclassical perturbation formalism (SCPF). The measured and calculated shift values and the measured A values have been compared to the existing data taken from available data sources.
Clinical Assessment Of The Quantitative Posturography System (Qps), Jacinta Browne, G. O'Hare, A. Finn, J. Colin
Clinical Assessment Of The Quantitative Posturography System (Qps), Jacinta Browne, G. O'Hare, A. Finn, J. Colin
Articles
The objectives of this study were to evaluate a novel design dynamic force platform the Quantitative Posturography System (QPS). The evaluation consisted of identifying the effects due to ageing and disease of the postural control system and also to examine the relationship between functional performance and postural sway. An AOVA design and Pearson-Product correlation design were used. Seventy healthy subjects, seven subjects with Parkinson’s disease and eight subjects with a history of falls took part in the study. It was found that the QPS was able to identify changes due to both the ageing process and disease on the postural …
Observational Limits On Quantum Geometry Effects, Tomasz J. Konopka '02, Seth Major
Observational Limits On Quantum Geometry Effects, Tomasz J. Konopka '02, Seth Major
Articles
Using a form of modified dispersion relations derived in the context of quantum geometry, we investigate limits set by current observations on potential corrections to Lorentz invariance. We use a phenomological model in which there are separate parameters for photons, leptons and hadrons. Constraints on these parameters are derived using thresholds for the processes of photon stability, photon absorption, vacuum Cerenkov radiation, pion stability and the GZK cutoff. Although the allowed region in parameter space is tightly constrained, non-vanishing corrections to Lorentz symmetry due to quantum geometry are consistent with current astrophysical observations.
Flow Patterns In A Two-Roll Mill, Christopher Hills
Flow Patterns In A Two-Roll Mill, Christopher Hills
Articles
The two-dimensional flow of a Newtonian fluid in a rectangular box that contains two disjoint, independently-rotating, circular boundaries is studied. The flow field for this two-roll mill is determined numerically using a finite-difference scheme over a Cartesian grid with variable horizontal and vertical spacing to accommodate satisfactorily the circular boundaries. To make the streamfunction numerically determinate we insist that the pressure field is everywhere single-valued. The physical character, streamline topology and transitions of the flow are discussed for a range of geometries, rotation rates and Reynolds numbers in the underlying seven-parameter space. An account of a preliminary experimental study of …
Some Irrational Generalised Moonshine From Orbifolds, Rossen Ivanov, Michael Tuite
Some Irrational Generalised Moonshine From Orbifolds, Rossen Ivanov, Michael Tuite
Articles
We verify the Generalised Moonshine conjectures for some irrational modular functions for theMonster centralisers related to the Harada-Norton, Held, M12 and L3(3) simple groups based on certain orbifolding constraints. We find explicitly the fixing groups of the hauptmoduls arising in each case.
Rational Generalized Moonshine From Abelian Orbifoldings Of The Moonshine Module, Rossen Ivanov, Michael Tuite
Rational Generalized Moonshine From Abelian Orbifoldings Of The Moonshine Module, Rossen Ivanov, Michael Tuite
Articles
We consider orbifoldings of the Moonshine Module with respect to the abelian group generated by a pair of commuting Monster group elements with one of prime order p = 2, 3, 5, 7 and the other of order pk for k = 1 or k prime. We show that constraints arising from meromorphic orbifold conformal field theory allow us to demonstrate that each orbifold partition function with rational coefficients is either constant or is a hauptmodul for an explicitly found modular fixing group of genus zero. We thus confirm in the cases considered the Generalised Moonshine conjectures for all rational …