Abstract

A new class of observables is introduced which aims to characterize the superstructure of an event, that is, features, such as color flow, which are not determined by the jet four-momenta alone. Traditionally, an event is described as having jets which are independent objects; each jet has some energy, size, and possible substructure such as subjets or heavy flavor content. This description discards information connecting the jets to each other, which can be used to determine if the jets came from decay of a color- singlet object, or if they were initiated by quarks or gluons. An example superstructure variable, pull, is presented as a simple handle on color flow. It can be used on an event-by-event basis as a tool for distinguishing previously irreducible backgrounds at the Tevatron and the LHC.

From the Cover…

.. epigraph:: “Townsend has written an excellent book that someone needed to write for the modern physics textbook market. He has given it the same care that he gave to his excellent quantum mechanics book.” -- Jeff Dunham, Middlebury College .. epigraph:: “When I read this book I immediately adopted it for my sophomore modern physics class. This is the best introduction to quantum mechanics available.” -- B. Paul Padley, Rice University

Abstract

Absorption enhancement in thin metal-backed solar cells caused by dipole scatterers embedded in the absorbing layer is studied using a semi-analytical approach. The method accounts for changes in the radiation rate produced by layers above and below the dipole, and treats incoherently the subsequent scattering of light in guided modes from other dipoles. We find large absorption enhancements for strongly coupled dipoles, exceeding the ergodic limit in some configurations involving lossless dipoles. An antireflection-coated 100-nm layer of a-Si:H on Ag absorbs up to 87% of incident above-gap light. Thin layers of both strong and weak absorbers show similar strongly enhanced absorption.

Recent Publications

Student authorFaculty author

61.

Jason Gallicchio and Matthew D. Schwartz

Seeing in Color: Jet Superstructure

Physical Review Letters 105 (2010) 022001.
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62.

John S. Townsend

Quantum Physics: a Fundamental Approach to Modern Physics

University Science Books, Sausalito, 2010.
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63.

Andrew P. Higginbotham, Octavi E. Semonin, Sandra A. Bruce, Clarence W. Chan, David A. Mann, M. Maurer, W. Bang, I. V. Churina, J. Osterholz, I. Kim, T. Ditmire, and Thomas D. Donnelly

Generation of Mie size microdroplet aerosols with applications in laser-driven fusion experiments

Review of Scientific Instruments 80 (2009) 063503.
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64.

J. Parker, David W. Mar, Joshua R. Puzey, John H. Hankinson, Kevin P. Byram, C. Lee, Michael K. Mayeda, Richard C. Haskell, Qimin Yang, S. Greenfield, and R. Epstein

Thermal links for the implementation of an optical refrigerator

Journal of Applied Physics 105 (2009) 013116.
65.

Peter N. Saeta, Harry A. Atwater, Vivian E. Ferry, Jeremy N. Munday, and Domenico Pacifici

How much can guided modes enhance absorption in thin solar cells?

Optics Express 17 (2009) 20975-20990.
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66.

Gregory Minton and Vatche Sahakian

New mechanism for nonlocality from string theory: UV-IR quantum entanglement and its imprints on the CMB

Physical Review D 77 (2008) 026008.
67.

S. Kneip, B. I. Cho, D. R. Symes, H. A. Sumeruk, G. Dyer, I. V. Churina, A. V. Belolipetski, A. Henig, O. Werhan, E. Förster, Thomas D. Donnelly, and T. Ditmire

K-shell Spectroscopy of Plasmas Created by Intense Laser Irradiation of Micron-scale Cone and Sphere Targets

High Energy Density Physics 4 (2008) 41-48.
68.

Junbo Park, S. M. Watson, Caitlin M. Furjanic, Dariya K. Draganova, M. J. Carey, J. A. Borchers, Chih-Yung Chen, Patricia D. Sparks, and James C. Eckert

Probing the Effect of Structural Roughness on Domain Wall Formation in Spin Valves Using the Off-Specular Reflectivity Technique

IEEE Transactions on Magnetism 44 (2008) 2839-2841.
69.

Junbo Park, K. W. Alt, Caitlin M. Furjanic, Dariya K. Draganova, Samuel D. Eisenberg, D. Tighe, M. J. Carey, J. A. Borchers, Patricia D. Sparks, and James C. Eckert

Thickness of the Pinned Layer as a Controlling Factor in Domain Wall Formation During Training in IrMn-based Spin Valves

Journal of Applied Physics 103 (2008) 07C111.
70.

H. A. Sumeruk, S. Kneip, D. R. Symes, I. V. Churina, A. V. Belolipetski, G. Dyer, J. Landry, G. Bansal, A. Bernstein, Thomas D. Donnelly, A. Karmakar, and T. Ditmire

Hot electron and x-ray production from intense laser irradiation of wavelength-scale polystyrene spheres

Physics of Plasmas 14 (2007) 062704.
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