Pulsed plasma enhanced chemical vapor deposition of fluorocarbon thin films for dielectric applications

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1999.Includes bibliographical references.by Catherine B. Labelle.Ph.D

Brandon LaBelle and Konstantinos Thomaidis: Vocal Positionings

This Salon conversation/podcast explores sound and meaning, the performativity of the self in listening and voicing, aural dramaturgies of inclusion/exclusion, and the intersections of history, politics and voice. It features excerpts from James Webb’s sound work A Series of Personal Questions Addressed to 5 Litres of Nigerian Crude Oil (2015) and from Thomaidis’s own autobiophonic piece A Voice Is. A Voice Has. A Voice Does (2018)

The flavor symmetry in the standard model and the triality symmetry

A Dirac fermion is expressed by a 4 component spinor which is a combination of two quaternions and which can be treated as an octonion. The octonion possesses the triality symmetry, which defines symmetry of fermion spinors and bosonic vector fields. The triality symmetry relates three sets of spinors and two sets of vectors, which are transformed among themselves via transformations $G_{23}, G_{12}, G_{13}$, $G_{123}$ and $G_{132}$. If the electromagnetic (EM) interaction is sensitive to the triality symmetry, i.e. EM probe selects one triality sector, EM signals from the 5 transformed world would not be detected, and be treated as the dark matter. According to an astrophysical measurement, the ratio of the dark to ordinary matter in the universe as a whole is almost exactly 5. We expect quarks are insensitive to the triality, and triality will appear as three times larger flavor degrees of freedom in the lattice simulation.Comment: 16 pages 8 figures, To be published in International Journal of Modern Physics

The pendulum swings back to scoliosis screening: screening policies for early detection and treatment of idiopathic scoliosis - current concepts and recommendations

This editorial article initiates the school scoliosis screening thematic series of the Scoliosis journal. The various issues on screening policies are discussed; clinical and practical recommendations of setting up school screening programs are also described

Relativistic and Binding Energy Corrections to Direct Photon Production In Upsilon Decay

A systematic gauge-invariant method is used to calculate the rate for an upsilon meson to decay inclusively into a prompt photon. An expansion is made in the quark relative velocity v, which is a small natural parameter for heavy quark systems. Inclusion of these O(v^2) corrections tends to increase the photon rate in the middle z range and to lower it for larger z, a feature supported by the data.Comment: 13 pages, LateX, One figure (to be published in Phys. Rev. D, Sept. 1, 1996

Adaptive soundscape design for liveable urban spaces: a hybrid methodology across environmental acoustics and sonic art

The aim of this research is to identify and implement soundscape improvement strategies in urban areas based on loudspeaker placements in the outdoor environment and the use of a computer-based system for adaptive soundscape generation, integrating sonic art practice with acoustic engineering rigour

Cusps in K --> 3 pi decays

The pion mass difference generates a pronounced cusp in K --> 3 pi decays. As has recently been pointed out by Cabibbo and Isidori, an accurate measurement of the cusp may allow one to pin down the S-wave pi pi scattering lengths to high precision. Here, we present and illustrate an effective field theory framework that allows one to determine the structure of this cusp in a straightforward manner. The strictures imposed by analyticity and unitarity are respected automatically.Comment: 14 pages, 3 figures, uses Elsevier styl

Effective field theories for QED bound states: extending Nonrelativistic QED to study retardation effects

Nonrelativistic QED bound states are difficult to study because of the presence of at least three widely different scales: the masses, three-momenta ($p_i$) and kinetic energies ($K_i$) of the constituents. Nonrelativistic QED (NRQED), an effective field theory developed by Caswell and Lepage, simplifies greatly bound state calculations by eliminating the masses as dynamical scales. As we demonstrate, NRQED diagrams involving only photons of energy $E_\gamma \simeq p_i$ contribute, in any calculation, to a unique order in $\alpha$. This is not the case, however, for diagrams involving photons with energies $E_\gamma \simeq K_i$ (``retardation effects"), for which no simple counting counting rules can be given. We present a new effective field theory in which the contribution of those ultra-soft photons can be isolated order by order in $\alpha$. This is effectively accomplished by performing a multipole expansion of the NRQED vertices.Comment: 39 pages, 9 Postscript figures, uses Rev.tex V3.0 and epsf.te