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2004

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Articles 66301 - 66330 of 71274

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Fourier-Domain Holography In Photorefractive Quantum-Well Films, K. Jeong, L. L. Peng, D. D. Nolte, M. R. Melloch Jan 2004

Fourier-Domain Holography In Photorefractive Quantum-Well Films, K. Jeong, L. L. Peng, D. D. Nolte, M. R. Melloch

Department of Physics and Astronomy Faculty Publications

Fourier-domain holography (FDH) is investigated as a candidate for holographic optical coherence imaging to produce real-time images of structure inside living tissue and turbid media. The effects of spatial filtering, the background intensity distributions, and the role of background noise in determining dynamic range are evaluated for both FDH and image-domain holography (IDH). The grating washout effect in FDH (edge enhancement) is removed by use of a vibrating diffuser that consequently improves the image quality. By comparing holographic images and background images of FDH and IDH we show that FDH provides a higher dynamic range and a higher image quality …

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Tev Gamma-Ray Observations Of The Galactic Center, K. Kosack, H. M. Badran, I. H. Bond, P. J. Boyle, S. M. Bradbury, J. H. Buckley, D. A. Carter-Lewis, O. Celik, V. Connaughton, W. Cui, M. Daniel, M. D'Vall, I. D. L. Perez, C. Duke, A. Falcone, D. J. Fegan, S. J. Fegan, J. P. Finley, L. F. Fortson, J. A. Gaidos, S. Gammell, K. Gibbs, G. H. Gillanders, J. Grube, K. Gutierrez, J. Hall, T. A. Hall, D. Hanna, A. M. Hillas, J. Holder, D. Horan, A. Jarvis, M. Jordan, G. E. Kenny, M. Kertzman, D. Kieda, J. Kildea, J. Knapp, H. Krawczynski, F. Krennrich, M. J. Lang, S. Le Bohec, E. Linton, J. Lloyd-Evans, A. Milovanovic, J. Mcenery, R. Moriarty, D. Muller, T. Nagai, S. Nolan, R. A. Ong, R. Pallassini, D. Petry, B. Power-Mooney, J. Quinn, M. Quinn, K. Ragan, P. Rebillot, P. T. Reynolds, H. J. Rose, M. Schroedter, G. H. Sembroski, S. P. Swordy, A. Syson, V. V. Vassiliev, S. P. Wakely, G. Walker, T. C. Weekes, J. Zweerink Jan 2004

Tev Gamma-Ray Observations Of The Galactic Center, K. Kosack, H. M. Badran, I. H. Bond, P. J. Boyle, S. M. Bradbury, J. H. Buckley, D. A. Carter-Lewis, O. Celik, V. Connaughton, W. Cui, M. Daniel, M. D'Vall, I. D. L. Perez, C. Duke, A. Falcone, D. J. Fegan, S. J. Fegan, J. P. Finley, L. F. Fortson, J. A. Gaidos, S. Gammell, K. Gibbs, G. H. Gillanders, J. Grube, K. Gutierrez, J. Hall, T. A. Hall, D. Hanna, A. M. Hillas, J. Holder, D. Horan, A. Jarvis, M. Jordan, G. E. Kenny, M. Kertzman, D. Kieda, J. Kildea, J. Knapp, H. Krawczynski, F. Krennrich, M. J. Lang, S. Le Bohec, E. Linton, J. Lloyd-Evans, A. Milovanovic, J. Mcenery, R. Moriarty, D. Muller, T. Nagai, S. Nolan, R. A. Ong, R. Pallassini, D. Petry, B. Power-Mooney, J. Quinn, M. Quinn, K. Ragan, P. Rebillot, P. T. Reynolds, H. J. Rose, M. Schroedter, G. H. Sembroski, S. P. Swordy, A. Syson, V. V. Vassiliev, S. P. Wakely, G. Walker, T. C. Weekes, J. Zweerink

Department of Physics and Astronomy Faculty Publications

We report a possible detection of TeV gamma rays from the Galactic center by the Whipple 10 m gamma-ray telescope. Twenty-six hours of data were taken over an extended period from 1995 through 2003 resulting in a total significance of 3.7 sigma. The measured excess corresponds to an integral flux of 1.6 x 10(-8) +/- 0.5 x 10(-8) (stat) +/- 0.3 x 10(-8) (sys) photons m(-2) s(-1) above an energy of 2.8 TeV, roughly 40% of the flux from the Crab Nebula at this energy. The 95% confidence region has an angular extent of about 15' and includes the position …

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The Vsop 5 Ghz Active Galactic Nucleus Survey. Ii. Data Calibration And Imaging, J. E. J. Lovell, G. A. Moellenbrock, S. Horiuchi, E. B. Fomalont, W. K. Scott, H. Hirabayashi, R. G. Dodson, S. M. Dougherty, P. G. Edwards, S. Frey, L. I. Gurvits, M. L. Lister, D. W. Murphy, Z. Paragi, B. G. Piner, Z. Q. Shen, A. R. Taylor, S. J. Tingay, Y. Asaki, D. Moffett, Y. Murata Jan 2004

The Vsop 5 Ghz Active Galactic Nucleus Survey. Ii. Data Calibration And Imaging, J. E. J. Lovell, G. A. Moellenbrock, S. Horiuchi, E. B. Fomalont, W. K. Scott, H. Hirabayashi, R. G. Dodson, S. M. Dougherty, P. G. Edwards, S. Frey, L. I. Gurvits, M. L. Lister, D. W. Murphy, Z. Paragi, B. G. Piner, Z. Q. Shen, A. R. Taylor, S. J. Tingay, Y. Asaki, D. Moffett, Y. Murata

Department of Physics and Astronomy Faculty Publications

The VLBI Space Observatory Programme (VSOP) mission is a Japanese-led project to study radio sources with sub-milliarcsecond angular resolution using an orbiting 8 m telescope, HALCA, and global arrays of Earth-based telescopes. Approximately 25% of the observing time has been devoted to a survey of compact active galactic nuclei (AGNs) at 5 GHz that are stronger than 1 Jy-the VSOP AGN Survey. This paper, the second in a series, describes the data calibration, source detection, self-calibration, imaging, and modeling and gives examples illustrating the problems specific to space VLBI. The VSOP Survey Web site, which contains all results and calibrated …

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Holographic Optical Coherence Imaging Of Rat Osteogenic Sarcoma Tumor Spheroids, P. Yu, M. Mustata, L. L. Peng, J. J. Turek, M. R. Melloch, P. M. W. French, D. D. Nolte Jan 2004

Holographic Optical Coherence Imaging Of Rat Osteogenic Sarcoma Tumor Spheroids, P. Yu, M. Mustata, L. L. Peng, J. J. Turek, M. R. Melloch, P. M. W. French, D. D. Nolte

Department of Physics and Astronomy Faculty Publications

Holographic optical coherence imaging is a full-frame variant of coherence-domain imaging. An optoelectronic semiconductor holographic film functions as a coherence filter placed before a conventional digital video camera that passes coherent (structure-bearing) light to the camera during holographic readout while preferentially rejecting scattered light. The data are acquired as a succession of en face images at increasing depth inside the sample in a fly-through acquisition. The samples of living tissue were rat osteogenic sarcoma multicellular tumor spheroids that were grown from a single osteoblast cell line in a bioreactor. Tumor spheroids are nearly spherical and have radial symmetry, presenting a …

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Observation Of M87 At 400 Gev With The Whipple 10 Meter Telescope, S. Le Bohec, H. M. Badran, I. H. Bond, P. J. Boyle, S. M. Bradbury, J. H. Buckley, D. A. Carter-Lewis, M. Catanese, O. Celik, W. Cui, M. Daniel, M. D'Vali, I. D. Perez, C. Duke, A. Falcone, D. J. Fegan, S. J. Fegan, J. P. Finley, L. F. Fortson, J. A. Gaidos, S. Gammell, K. Gibbs, G. H. Gillanders, J. Grube, J. Hall, T. A. Hall, D. Hanna, A. M. Hillas, J. Holder, D. Horan, A. Jarvis, M. Jordan, G. E. Kenny, M. Kertzman, D. Kieda, J. Kildea, J. Knapp, K. Kosack, H. Krawczynski, F. Krennrich, M. J. Lang, E. Linton, J. Lloyd-Evans, A. Milovanovic, P. Moriarty, D. Muller, T. Nagai, S. Nolan, R. A. Ong, R. Pallassini, D. Petry, H. J. Rose, M. Schroedter, G. H. Sembroski, S. P. Swordy, A. Syson, V. V. Vassiliev, S. P. Wakely, G. Walker, T. C. Weekes, J. Zweerink Jan 2004

Observation Of M87 At 400 Gev With The Whipple 10 Meter Telescope, S. Le Bohec, H. M. Badran, I. H. Bond, P. J. Boyle, S. M. Bradbury, J. H. Buckley, D. A. Carter-Lewis, M. Catanese, O. Celik, W. Cui, M. Daniel, M. D'Vali, I. D. Perez, C. Duke, A. Falcone, D. J. Fegan, S. J. Fegan, J. P. Finley, L. F. Fortson, J. A. Gaidos, S. Gammell, K. Gibbs, G. H. Gillanders, J. Grube, J. Hall, T. A. Hall, D. Hanna, A. M. Hillas, J. Holder, D. Horan, A. Jarvis, M. Jordan, G. E. Kenny, M. Kertzman, D. Kieda, J. Kildea, J. Knapp, K. Kosack, H. Krawczynski, F. Krennrich, M. J. Lang, E. Linton, J. Lloyd-Evans, A. Milovanovic, P. Moriarty, D. Muller, T. Nagai, S. Nolan, R. A. Ong, R. Pallassini, D. Petry, H. J. Rose, M. Schroedter, G. H. Sembroski, S. P. Swordy, A. Syson, V. V. Vassiliev, S. P. Wakely, G. Walker, T. C. Weekes, J. Zweerink

Department of Physics and Astronomy Faculty Publications

We present results from observations taken with the Whipple 10 m very high energy gamma-ray telescope with maximal sensitivity at 400 GeV during 39 hr between 2000 and 2003 in the direction of the giant radio galaxy M87. Using the entire data set, we derive a 99% confidence level upper limit on the flux of gamma-ray emission above 400 GeV from M87 to be less than or equal to 6: 9; 10(-1)2 cm(-2) s(-1). This suggests variability at the 90% confidence level when compared to the flux measured by the HEGRA collaboration in 1999 if the differential spectrum is steeper …

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Variable Responses Of Western Us Glaciers During The Last Deglaciation, J. M. Licciardi, P. U. Clark, E. J. Brook, D. Elmore, P. Sharma Jan 2004

Variable Responses Of Western Us Glaciers During The Last Deglaciation, J. M. Licciardi, P. U. Clark, E. J. Brook, D. Elmore, P. Sharma

Department of Physics and Astronomy Faculty Publications

Cosmogenic Be-10 exposure ages from moraines in the Wallowa Mountains, Oregon, identify two maximal late Pleistocene glaciations at 21.1 +/- 0.4 ka and 17.0 +/- 0.3 ka and a minor glacial event at 10.2 +/- 0.6 ka. Our new high-resolution chronology, integrated with other well-dated glacial records from the western United States, demonstrates substantial differences in the synoptic responses of western U.S. glaciers to climate forcing associated with the global Last Glacial Maximum and subsequent millennial-scale events originating in the North Atlantic region. These variable synoptic glacier responses identify large changes in the relative contributions of regional to global controls …

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High-Speed Label-Free Detection By Spinning-Disk Micro-Interferometry, M. M. Varma, H. D. Inerowicz, F. E. Regnier, D. D. Nolte Jan 2004

High-Speed Label-Free Detection By Spinning-Disk Micro-Interferometry, M. M. Varma, H. D. Inerowicz, F. E. Regnier, D. D. Nolte

Department of Physics and Astronomy Faculty Publications

Spinning-disk interferometers are a new class of analytic sensors to detect immobilized biomolecules with high speed and high sensitivity. The disks are composed of a large number of surface-normal self-referencing interferometers, analogous to an optical CD, but operating on the principle of microdiffraction quadrature that achieves sensitive linear detection of bound molecules. The surface-normal structures have a small footprint of only 20 mum each, allowing potential integration to over a million interferometric elements per disk. We have fabricated interferometric microstructures on silicon and on dielectric mirror disks to demonstrate the basic principles of the BioCD. We have detected the presence …

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Electrochromic Shift Of Chlorophyll Absorption In Photosystem I From Synechocystis Sp Pcc 6803: A Probe Of Optical And Dielectric Properties Around The Secondary Electron Acceptor, N. Dashdorj, W. Xu, P. Martinsson, P. R. Chitnis, S. Savikhin Jan 2004

Electrochromic Shift Of Chlorophyll Absorption In Photosystem I From Synechocystis Sp Pcc 6803: A Probe Of Optical And Dielectric Properties Around The Secondary Electron Acceptor, N. Dashdorj, W. Xu, P. Martinsson, P. R. Chitnis, S. Savikhin

Department of Physics and Astronomy Faculty Publications

Nanosecond absorption dynamics at similar to685 nm after excitation of photosystem I ( PS I) from Synechocystis sp. PCC 6803 is consistent with electrochromic shift of absorption bands of the Chl a pigments in the vicinity of the secondary electron acceptor A(1). Based on experimental optical data and structure-based simulations, the effective local dielectric constant has been estimated to be between 3 and 20, which suggests that electron transfer in PS I is accompanied by considerable protein relaxation. Similar effective dielectric constant values have been previously observed for the bacterial photosynthetic reaction center and indicate that protein reorganization leading to …

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Physical Modeling Of The Piano, N. Giordano, M. Jiang Jan 2004

Physical Modeling Of The Piano, N. Giordano, M. Jiang

Department of Physics and Astronomy Faculty Publications

A project aimed at constructing a physical model of the piano is described. Our goal is to calculate the sound produced by the instrument entirely from Newton's laws. The structure of the model is described along with experiments that augment and test the model calculations. The state of the model and what can be learned from it are discussed.

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The Use Of Ultrasound And Shear Oscillatory Tests To Characterize The Effect Of Mixing Time On The Rheological Properties Of Dough, K. A. Ross, L. J. Pyrak-Nolte, O. H. Campanella Jan 2004

The Use Of Ultrasound And Shear Oscillatory Tests To Characterize The Effect Of Mixing Time On The Rheological Properties Of Dough, K. A. Ross, L. J. Pyrak-Nolte, O. H. Campanella

Department of Physics and Astronomy Faculty Publications

This work examined the effect of mixing time on three different flour dough systems: bread-flour wheat dough, all-purpose flour wheat dough, and cake flour wheat dough. Both ultrasound and conventional rheology techniques were used to examine the effect of mixing on these dough systems. Fundamental ultrasound results were obtained at 3.5 MHz; velocity and attenuation showed peak values at the optimum mixing time. Similar results were observed by using conventional rheology, which showed peaks in both storage and loss shear moduli at the optimum mixing time. Thus, there was an agreement between the results obtained by conventional rheology and ultrasound …

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Linking Pressure And Saturation Through Interfacial Areas In Porous Media, J. T. Cheng, L. J. Pyrak-Nolte, D. D. Nolte, N. J. Giordano Jan 2004

Linking Pressure And Saturation Through Interfacial Areas In Porous Media, J. T. Cheng, L. J. Pyrak-Nolte, D. D. Nolte, N. J. Giordano

Department of Physics and Astronomy Faculty Publications

Using transparent microfluidic cells to study the two-phase properties of a synthetic porous medium, we establish that the interfacial area per volume between nonwetting and wetting fluids lifts the ambiguity associated with the hysteretic relationship between capillary pressure and saturation in porous media. The interface between the nonwetting and wetting phases is composed of two subsets: one with a unique curvature determined by the capillary pressure, and the other with a distribution of curvatures dominated by disjoining pressure. This work provides experimental support for recent theoretical predictions that the capillary-dominated subset plays a role analogous to a state variable. Any …

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Cdf Run Iib Silicon Detector: The Innermost Layer, P. Merkel, P. Azzi, N. Bacchetta, D. Bisello, G. Busetto, K. Hara, S. Kim, C. Manea, Z. Wang, S. Behari, P. Maksimovic, D. Benjamin, S. Cabrera, M. Kruse, G. Bolla, D. Bortoletto, A. Canepa, J. P. Fernandez, P. Booth, P. Cooke, M. Cascella, G. Cardoso, G. Derylo, B. Flaugher, M. Hrycyk, N. Kuznetsova, P. Lukens, T. Nelson, Y. Orlov, W. Wester, J. C. Yun, M. Chertok, B. Holbrook, R. Lander, T. Landry, D. Pellett, A. Soha, W. Yao, C. I. Ciobanu, T. Junk, E. J. Feng, J. Freeman, L. Galtieri, M. Garcia-Sciveres, C. Haber, P. J. Lujan, E. Mandelli, M. Weber, W. Yao, F. Zetti, S. Zimmermann, J. Goldstein, R. Harr, C. Hill, A. Himmel, J. Incandela, D. Stuart, K. Kobayashi, I. Nakano, R. Tanaka, D. J. Kong, Y. C. Yang, R. Lauhakangas, R. Orava, K. Osterberg, R. S. Lu, S. N. Min, T. Okusawa, K. Yamamoto, M. Tavi, S. Zucchelli, S. C. Hong, E. J. Jeon, K. K. Joo, J. Lee Jan 2004

Cdf Run Iib Silicon Detector: The Innermost Layer, P. Merkel, P. Azzi, N. Bacchetta, D. Bisello, G. Busetto, K. Hara, S. Kim, C. Manea, Z. Wang, S. Behari, P. Maksimovic, D. Benjamin, S. Cabrera, M. Kruse, G. Bolla, D. Bortoletto, A. Canepa, J. P. Fernandez, P. Booth, P. Cooke, M. Cascella, G. Cardoso, G. Derylo, B. Flaugher, M. Hrycyk, N. Kuznetsova, P. Lukens, T. Nelson, Y. Orlov, W. Wester, J. C. Yun, M. Chertok, B. Holbrook, R. Lander, T. Landry, D. Pellett, A. Soha, W. Yao, C. I. Ciobanu, T. Junk, E. J. Feng, J. Freeman, L. Galtieri, M. Garcia-Sciveres, C. Haber, P. J. Lujan, E. Mandelli, M. Weber, W. Yao, F. Zetti, S. Zimmermann, J. Goldstein, R. Harr, C. Hill, A. Himmel, J. Incandela, D. Stuart, K. Kobayashi, I. Nakano, R. Tanaka, D. J. Kong, Y. C. Yang, R. Lauhakangas, R. Orava, K. Osterberg, R. S. Lu, S. N. Min, T. Okusawa, K. Yamamoto, M. Tavi, S. Zucchelli, S. C. Hong, E. J. Jeon, K. K. Joo, J. Lee

Department of Physics and Astronomy Faculty Publications

The innermost layer (L00) of the Run IIa silicon detector of CDF was planned to be replaced for the high luminosity Tevatron upgrade of Run IIb. This new silicon layer (L0) is designed to be a radiation tolerant replacement for the otherwise very similar L00 from Run IIa. The data are read out via long, fine-pitch, low-mass cables allowing the hybrids with the chips to sit at higher z(similar to 70 cm), outside of the tracking volume. The design and first results from the prototyping phase are presented. Special focus is placed on the amount and the structure of induced …

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Sensors For The Cdf Run2b Silicon Detector, T. Akimoto, M. Aoki, P. Azzi, N. Bacchetta, S. Behari, D. Benjamin, D. Bisello, G. Bolla, P. Booth, D. Bortoletto, A. Burghard, G. Busetto, S. Cabrera, A. Canepa, G. Cardoso, M. Chertok, C. I. Ciobanu, P. Cooke, G. Derylo, I. Fang, E. J. Feng, J. P. Fernandez, B. Flaugher, J. Freeman, L. Galtieri, J. Galyardt, M. Garcia-Sciveres, G. Giurgiu, I. Gorelov, C. Haber, D. Hale, K. Hara, R. Harr, C. Hill, M. Hoeferkamp, J. Hoff, B. Holbrook, S. C. Hong, M. Hrycyk, T. H. Hsiung, J. Incandela, E. J. Jeon, K. K. Joo, T. Junk, H. Kahkola, S. Karjalainen, S. Kim, K. Kobayashi, D. J. Kong, B. Krieger, M. Kruse, S. Kyre, R. Lander, T. Landry, R. Lauhakangas, J. Lee, R. S. Lu, P. J. Lujan, P. Lukens, E. Mandelli, C. Manea, P. Maksimovic, P. Merkel, S. N. Min, S. Moccia, Y. Nakamura, I. Nakano, D. Naoumov, T. Nelson, B. Nord, J. Novak, T. Okusawa, R. Orava, Y. Orlov, K. Osterberg, D. Pantano, V. Pavlicek, D. Pellett, J. Pursley, P. Riipinen, B. Schuyler, S. Seidel, A. Shenai, A. Soha, D. Stuart, R. Tanaka, M. Tavi, H. Von Der Lippe, J. P. Walder, Z. Wang, P. Watje, M. Weber, W. Wester, K. Yamamoto, Y. C. Yang, W. Yao, W. Yao, R. Yarema, H. Yoshitama, J. C. Yun, F. Zetti, T. Zimmerman, S. Zimmermann, S. Zucchelli Jan 2004

Sensors For The Cdf Run2b Silicon Detector, T. Akimoto, M. Aoki, P. Azzi, N. Bacchetta, S. Behari, D. Benjamin, D. Bisello, G. Bolla, P. Booth, D. Bortoletto, A. Burghard, G. Busetto, S. Cabrera, A. Canepa, G. Cardoso, M. Chertok, C. I. Ciobanu, P. Cooke, G. Derylo, I. Fang, E. J. Feng, J. P. Fernandez, B. Flaugher, J. Freeman, L. Galtieri, J. Galyardt, M. Garcia-Sciveres, G. Giurgiu, I. Gorelov, C. Haber, D. Hale, K. Hara, R. Harr, C. Hill, M. Hoeferkamp, J. Hoff, B. Holbrook, S. C. Hong, M. Hrycyk, T. H. Hsiung, J. Incandela, E. J. Jeon, K. K. Joo, T. Junk, H. Kahkola, S. Karjalainen, S. Kim, K. Kobayashi, D. J. Kong, B. Krieger, M. Kruse, S. Kyre, R. Lander, T. Landry, R. Lauhakangas, J. Lee, R. S. Lu, P. J. Lujan, P. Lukens, E. Mandelli, C. Manea, P. Maksimovic, P. Merkel, S. N. Min, S. Moccia, Y. Nakamura, I. Nakano, D. Naoumov, T. Nelson, B. Nord, J. Novak, T. Okusawa, R. Orava, Y. Orlov, K. Osterberg, D. Pantano, V. Pavlicek, D. Pellett, J. Pursley, P. Riipinen, B. Schuyler, S. Seidel, A. Shenai, A. Soha, D. Stuart, R. Tanaka, M. Tavi, H. Von Der Lippe, J. P. Walder, Z. Wang, P. Watje, M. Weber, W. Wester, K. Yamamoto, Y. C. Yang, W. Yao, W. Yao, R. Yarema, H. Yoshitama, J. C. Yun, F. Zetti, T. Zimmerman, S. Zimmermann, S. Zucchelli

Department of Physics and Astronomy Faculty Publications

We describe the characteristics of silicon microstrip sensors fabricated by Hamamatsu Photonics; for the CDF Run 2b silicon detector. A total of 953 sensors, including 117 prototype sensors, have been produced and tested. Five sensors were irradiated with neutrons up to 1.4 x 10(14) n/cm(2) as a part of the sensor quality assurance program. The electrical and mechanical characteristics are found to be superior in all aspects and fulfill our specifications. We comment on charge-up susceptibility of the sensors that employ a <100> crystal structure.

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Cdf Run Iib Silicon: Design And Testing, R. S. Lu, T. Akimoto, M. Aoki, P. Azzi, N. Bacchetta, S. Behari, D. Benjamin, D. Bisello, G. Bolla, D. Bortoletto, G. Busetto, S. Cabrera, A. Canepa, G. Cardoso, M. Chertok, C. I. Ciobanu, G. Derylo, I. Fang, E. J. Feng, J. P. Fernandez, B. Flaugher, J. Freeman, L. Galtieri, J. Galyardt, M. Garcia-Sciveres, G. Giurgiu, C. Haber, D. Hale, K. Hara, R. Harr, C. Hill, J. Hoff, B. Holbrook, S. C. Hong, M. Hrycyk, T. H. Hsiung, J. Incandela, E. J. Jeon, K. K. Joo, T. Junk, H. Kahkola, S. Karjalainen, S. Kim, K. Kobayashi, D. J. Kong, B. Krieger, M. Kruse, N. Kuznetsova, S. Kyre, R. Lander, T. Landry, R. Lauhakangas, J. Lee, R. J. Lujan, P. Lukens, E. Mandelli, C. Manea, P. Maksimovic, P. Merkel, S. N. Min, S. Moccia, I. Nakano, T. Nelson, B. Nord, J. Novak, T. Okusawa, R. Orava, Y. Orlov, K. Osterberg, D. Pantano, V. Pavlicek, D. Pellett, J. Pursley, P. Riipinen, B. Schuyler, A. Shenai, A. Soha, D. Stuart, R. Tanaka, M. Tavi, H. Von Der Lippe, J. P. Walder, Z. Wang, M. Weber, W. Wester, K. Yamamoto, Y. C. Yang, W. Yao, W. Yao, R. Yarema, J. C. Yun, F. Zetti, T. Zimmerman, S. Zimmermann, S. Zucchelli Jan 2004

Cdf Run Iib Silicon: Design And Testing, R. S. Lu, T. Akimoto, M. Aoki, P. Azzi, N. Bacchetta, S. Behari, D. Benjamin, D. Bisello, G. Bolla, D. Bortoletto, G. Busetto, S. Cabrera, A. Canepa, G. Cardoso, M. Chertok, C. I. Ciobanu, G. Derylo, I. Fang, E. J. Feng, J. P. Fernandez, B. Flaugher, J. Freeman, L. Galtieri, J. Galyardt, M. Garcia-Sciveres, G. Giurgiu, C. Haber, D. Hale, K. Hara, R. Harr, C. Hill, J. Hoff, B. Holbrook, S. C. Hong, M. Hrycyk, T. H. Hsiung, J. Incandela, E. J. Jeon, K. K. Joo, T. Junk, H. Kahkola, S. Karjalainen, S. Kim, K. Kobayashi, D. J. Kong, B. Krieger, M. Kruse, N. Kuznetsova, S. Kyre, R. Lander, T. Landry, R. Lauhakangas, J. Lee, R. J. Lujan, P. Lukens, E. Mandelli, C. Manea, P. Maksimovic, P. Merkel, S. N. Min, S. Moccia, I. Nakano, T. Nelson, B. Nord, J. Novak, T. Okusawa, R. Orava, Y. Orlov, K. Osterberg, D. Pantano, V. Pavlicek, D. Pellett, J. Pursley, P. Riipinen, B. Schuyler, A. Shenai, A. Soha, D. Stuart, R. Tanaka, M. Tavi, H. Von Der Lippe, J. P. Walder, Z. Wang, M. Weber, W. Wester, K. Yamamoto, Y. C. Yang, W. Yao, W. Yao, R. Yarema, J. C. Yun, F. Zetti, T. Zimmerman, S. Zimmermann, S. Zucchelli

Department of Physics and Astronomy Faculty Publications

The various generations of Silicon Vertex Detectors (SVX, SVX', SVXII) for Collider Detector at Fermilab (CDF) at the Fermilab Tevatron have been fundamental tools for heavy-flavor tagging via secondary vertex detection. The CDF Run IIb Silicon Vertex Detector (SVXIIb) has been designed to be a radiation-tolerant replacement for the currently installed SVXII because SVXII was not expected to survive the Tevatron luminosity anticipated for Run IIb. One major change in the new design is the use of a single mechanical and electrical element throughout the array. This element, called a stave, carries six single-sided silicon sensors on each side and …

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Position Dependence Of Charge Collection In Prototype Sensors For The Cms Pixel Detector, T. Rohe, D. Bortoletto, V. Chiochia, L. M. Cremaldi, S. Cucciarelli, A. Dorokhov, M. Konecki, K. Prokofiev, C. Regenfus, D. A. Sanders, S. H. Son, T. Speer, M. Swartz Jan 2004

Position Dependence Of Charge Collection In Prototype Sensors For The Cms Pixel Detector, T. Rohe, D. Bortoletto, V. Chiochia, L. M. Cremaldi, S. Cucciarelli, A. Dorokhov, M. Konecki, K. Prokofiev, C. Regenfus, D. A. Sanders, S. H. Son, T. Speer, M. Swartz

Department of Physics and Astronomy Faculty Publications

This paper reports on the sensor R&D activity for the CMS pixel detector. Devices featuring several design and technology options have been irradiated up to a proton fluence(1) of I X 10(15) n(eq)/cm(2) at the CERN PS. Afterward, they were bump bonded to unirradiated readout chips and tested using high energy pions in the H2 beam line of the CERN SPS. The readout chip allows a nonzero suppressed full analogue readout and therefore a good characterization of the sensors in terms of noise and charge collection properties. The position dependence of signal is presented and the differences between the two …

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Magnetic Measurements On Ferromagnetic Behavior In The Bulk Ii-Vi Diluted Magnetic Semiconductor Zn1-Xcrxte, T. M. Pekarek, D. J. Arenas, B. C. Crooker, I. Miotkowski, A. K. Ramdas Jan 2004

Magnetic Measurements On Ferromagnetic Behavior In The Bulk Ii-Vi Diluted Magnetic Semiconductor Zn1-Xcrxte, T. M. Pekarek, D. J. Arenas, B. C. Crooker, I. Miotkowski, A. K. Ramdas

Department of Physics and Astronomy Faculty Publications

Magnetic measurements on the ferromagnetic behavior in the bulk II-VI diluted magnetic semiconductor Zn1-xCrxTe were made on two x=0.0033 single crystals taken from different regions of the same boule. Ferromagnetism was verified in both samples by an Arrott plot analysis with a transition temperature at 365 K (well above room temperature). For both samples at room temperature, the coercive field is similar to0.0100 T and the remanent magnetization is 23% of the saturated value. The similarity in the observed ferromagnetic behavior between the two samples suggests that a stable CryTez or possibly ZnxCryTez precipitate phase is responsible, although a Cr-rich …

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Cdf Run Iib Silicon Detector: Electrical Performance And Deadtime-Less Operation, T. Akimoto, M. Aoki, P. Azzi, N. Bacchetta, S. Behari, D. Benjamin, D. Bisello, G. Bolla, D. Bortoletto, G. Busetto, S. Cabrera, A. Canepa, G. Cardoso, M. Chertok, C. I. Ciobanu, G. Derylo, I. Fang, E. J. Feng, J. P. Fernandez, B. Flaugher, J. Freeman, L. Galtieri, J. Galyardt, M. Garcia-Sciveres, G. Giurgiu, C. Haber, D. Hale, K. Hara, R. Harr, C. Hill, J. Hoff, B. Holbrook, S. C. Hong, M. Hrycyk, T. H. Hsiung, J. Incandela, E. J. Jeon, K. K. Joo, T. Junk, H. Kahkola, S. Karjalainen, S. Kim, K. Kobayashi, D. J. Kong, B. Krieger, M. Kruse, N. Kuznetsova, S. Kyre, R. Lander, T. Landry, R. Lauhakangas, J. Lee, R. S. Lu, P. Lujan, P. Lukens, E. Mandelli, C. Manea, P. Maksimovic, P. Merkel, S. N. Min, S. Moccia, I. Nakano, T. Nelson, B. Nord, J. Novak, T. Okusawa, R. Orava, Y. Orlov, K. Osterberg, D. Pantano, V. Pavlicek, D. Pellett, J. Pursley, R. Riipinen, B. Schuyler, A. Shenai, A. Soha, D. Stuart, R. Tanaka, M. Tavi, H. Von Der Lippe, J. P. Walder, Z. Wang, M. Weber, W. Wester, K. Yamamoto, Y. C. Yang, W. Yao, W. Yao, R. Yarema, J. C. Yun, F. Zetti, T. Zimmerman, S. Zimmermann, S. Zucchelli Jan 2004

Cdf Run Iib Silicon Detector: Electrical Performance And Deadtime-Less Operation, T. Akimoto, M. Aoki, P. Azzi, N. Bacchetta, S. Behari, D. Benjamin, D. Bisello, G. Bolla, D. Bortoletto, G. Busetto, S. Cabrera, A. Canepa, G. Cardoso, M. Chertok, C. I. Ciobanu, G. Derylo, I. Fang, E. J. Feng, J. P. Fernandez, B. Flaugher, J. Freeman, L. Galtieri, J. Galyardt, M. Garcia-Sciveres, G. Giurgiu, C. Haber, D. Hale, K. Hara, R. Harr, C. Hill, J. Hoff, B. Holbrook, S. C. Hong, M. Hrycyk, T. H. Hsiung, J. Incandela, E. J. Jeon, K. K. Joo, T. Junk, H. Kahkola, S. Karjalainen, S. Kim, K. Kobayashi, D. J. Kong, B. Krieger, M. Kruse, N. Kuznetsova, S. Kyre, R. Lander, T. Landry, R. Lauhakangas, J. Lee, R. S. Lu, P. Lujan, P. Lukens, E. Mandelli, C. Manea, P. Maksimovic, P. Merkel, S. N. Min, S. Moccia, I. Nakano, T. Nelson, B. Nord, J. Novak, T. Okusawa, R. Orava, Y. Orlov, K. Osterberg, D. Pantano, V. Pavlicek, D. Pellett, J. Pursley, R. Riipinen, B. Schuyler, A. Shenai, A. Soha, D. Stuart, R. Tanaka, M. Tavi, H. Von Der Lippe, J. P. Walder, Z. Wang, M. Weber, W. Wester, K. Yamamoto, Y. C. Yang, W. Yao, W. Yao, R. Yarema, J. C. Yun, F. Zetti, T. Zimmerman, S. Zimmermann, S. Zucchelli

Department of Physics and Astronomy Faculty Publications

The main building block and readout unit of the planned CDF Run IIb silicon detector is a "stave," a highly integrated mechanical, thermal, and electrical structure. One of its characteristic features is a copper-on-Kapton flexible cable for power, high voltage, data transmission, and control signals that is placed directly below the silicon microstrip sensors. The dense packaging makes deadtime-less operation of the stave a challenge since coupling of bus cable activity into the silicon sensors must be suppressed efficiently. The stave design features relevant for deadtime-less operation are discussed. The electrical performance achieved with stave prototypes is presented.

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Single-Phase Flow In A Rock Fracture: Micro-Model Experiments And Network Flow Simulation, J. T. Cheng, J. P. Morris, J. Tran, A. Lumsdaine, N. J. Giordano, D. D. Nolte, L. J. Pyrak-Nolte Jan 2004

Single-Phase Flow In A Rock Fracture: Micro-Model Experiments And Network Flow Simulation, J. T. Cheng, J. P. Morris, J. Tran, A. Lumsdaine, N. J. Giordano, D. D. Nolte, L. J. Pyrak-Nolte

Department of Physics and Astronomy Faculty Publications

No abstract provided.

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Secure Group Communication Using Robust Contributory Key Agreement, Y. Amir, Y. Kim, C. Nita-Rotaru, J. L. Schultz, J. Stanton, G. Tsudik Jan 2004

Secure Group Communication Using Robust Contributory Key Agreement, Y. Amir, Y. Kim, C. Nita-Rotaru, J. L. Schultz, J. Stanton, G. Tsudik

Department of Physics and Astronomy Faculty Publications

Contributory group key agreement protocols generate group keys based on contributions of all group members. Particularly appropriate for relatively small collaborative peer groups, these protocols are resilient to many types of attacks. Unlike most group key distribution protocols, contributory group key agreement protocols offer strong security properties such as key independence and perfect forward secrecy. This paper presents the first robust contributory key agreement protocol resilient to any sequence of group changes. The protocol, based on the Group Diffie-Hellman contributory key agreement, uses the services of a group communication system supporting Virtual Synchrony semantics. We prove that it provides both …

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Precise Determination Of The Casimir Force And First Realization Of A "Casimir Less" Experiment, R. S. Decca, D. Lopez, H. B. Chan, E. Fischbach, G. L. Klimchitskaya, D. E. Krause, V. M. Mostepanenkot Jan 2004

Precise Determination Of The Casimir Force And First Realization Of A "Casimir Less" Experiment, R. S. Decca, D. Lopez, H. B. Chan, E. Fischbach, G. L. Klimchitskaya, D. E. Krause, V. M. Mostepanenkot

Department of Physics and Astronomy Faculty Publications

We present improved Casimir effect measurements. The attractive force between a metallized sphere and the coated plate of a Si microelectro mechanical oscillator is measured with unparalleled precision. The same setup, but in a dynamic scheme, yields a determination of the Casimir pressure between two infinite plates. Since the Casimir force is the dominant interaction in the 0.11 mum range under these experimental conditions, it acts as a background in the search for new forces in the submicrometer range. We report our progress in the realization of an experiment where the effect of the Casimir force is minimized (a "Casimir-less" …

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Determination Of Ultrasonic-Based Rheological Properties Of Dough During Fermentation, S. Y. Lee, L. J. Pyrak-Nolte, O. Campanella Jan 2004

Determination Of Ultrasonic-Based Rheological Properties Of Dough During Fermentation, S. Y. Lee, L. J. Pyrak-Nolte, O. Campanella

Department of Physics and Astronomy Faculty Publications

An ultrasonic technique was used to study the changes of the rheological properties of dough during fermentation at 37C and compared with the extensional properties of fermented dough obtained from tensile tests carried out in a Universal Testing Machine. The velocity and attenuation of a longitudinal wave (P-wave) propagated through the dough samples were measured and analyzed to obtain the viscoelastic moduli of the dough; the storage modulus M' and the loss modulus M". These moduli include both the bulk and the shear moduli. A wavelet analysis also was used to determine the effect of frequency on the ultrasonic-based viscoelastic …

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Adaptive Optical Coherence-Domain Reflectometry Using Photorefractive Quantum Wells, L. L. Peng, D. D. Nolte, Y. Ping, M. R. Melloch Jan 2004

Adaptive Optical Coherence-Domain Reflectometry Using Photorefractive Quantum Wells, L. L. Peng, D. D. Nolte, Y. Ping, M. R. Melloch

Department of Physics and Astronomy Faculty Publications

Adaptive optical-coherence-domain reflectometry (OCDR) is performed by use of an adaptive interferometer and homodyne detection. The adaptive element of the interferometer is a photorefractive quantum-well device in a two-wave mixing geometry. The mixing self-adaptively maintains constant relative phase between the signal and reference waves and dynamically compensates gross movements of the sample or optical components as well as image speckle. The application described here is used for laser ranging into and through turbid media. Adaptive OCDR is a bridge between conventional optical coherence tomography and adaptive holographic optical coherence imaging. The insertion loss for the adaptive performance is -15 dB, …

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Quantitative Vibrational Dynamics Of Iron In Nitrosyl Porphyrins, B. M. Leu, M. Z. Zgierski, G. R. A. Wyllie, W. R. Scheidt, W. Sturhahn, E. E. Alp, S. M. Durbin, J. T. Sage Jan 2004

Quantitative Vibrational Dynamics Of Iron In Nitrosyl Porphyrins, B. M. Leu, M. Z. Zgierski, G. R. A. Wyllie, W. R. Scheidt, W. Sturhahn, E. E. Alp, S. M. Durbin, J. T. Sage

Department of Physics and Astronomy Faculty Publications

We use quantitative experimental and theoretical approaches to characterize the vibrational dynamics of the Fe atom in porphyrins designed to model heme protein active sites. Nuclear resonance vibrational spectroscopy (NRVS) yields frequencies, amplitudes, and directions for Fe-57 vibrations in a series of ferrous nitrosyl porphyrins, which provide a benchmark for evaluation of quantum chemical vibrational calculations. Detailed normal mode predictions result from DFT calculations on ferrous nitrosyl tetraphenylporphyrin Fe(TPP)(NO), its cation [Fe(TPP)(NO)]1, and ferrous nitrosyl porphine Fe(P)(NO). Differing functionals lead to significant variability in the predicted Fe-NO bond length and frequency for Fe(TPP)(NO). Otherwise, quantitative comparison of calculated and measured …

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Broadened Far-Infrared Absorption Spectra For Hydrated And Dehydrated Myoglobin, C. F. Zhang, E. Tarhan, A. K. Ramdas, A. M. Weiner, S. M. Durbin Jan 2004

Broadened Far-Infrared Absorption Spectra For Hydrated And Dehydrated Myoglobin, C. F. Zhang, E. Tarhan, A. K. Ramdas, A. M. Weiner, S. M. Durbin

Department of Physics and Astronomy Faculty Publications

The far-infrared absorption spectra of myoglobin powder at hydration levels between 3.6 and 42 wt% were measured with terahertz time-domain spectroscopy and Fourier transform infrared spectroscopy. Absorption is dominated by the water content, but even the driest specimens have a nearly continuous spectrum without identifiable sharp features. Inhomogeneous broadening plus the intrinsically high spectral density of vibrational modes in the region below 2.0 THz apparently combine to obscure the lowest frequency vibrational modes expected for protein molecules of this size. A continuous absorption spectrum for hydrated protein powders suggests that the absorption mechanisms are similar to those in liquid water, …

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Characterisation Of Frozen Orange Juice By Ultrasound And Wavelet Analysis, S. Lee, L. J. Pyrak-Nolte, P. Cornillon, O. Campanella Jan 2004

Characterisation Of Frozen Orange Juice By Ultrasound And Wavelet Analysis, S. Lee, L. J. Pyrak-Nolte, P. Cornillon, O. Campanella

Department of Physics and Astronomy Faculty Publications

Ultrasound technology was used to analyse the freezing behaviour of orange juice. The ultrasonic properties of orange juice, specifically velocity and attenuation coefficient, were characterised as the temperature was decreased from 20 to -50degreesC. The results were compared with NMR free induction decay data and correlated with the amount of unfrozen water present in the frozen sample. The velocities of longitudinal waves (P-wave) and shear waves (S-wave) in frozen orange juice were measured, yielding values of around 4000 and 2000 m s(-1) respectively. They were related to the amount of unfrozen water in the frozen sample. The elastic moduli of …

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Unraveling The Exposure Histories Of Aubrites, K. C. Welten, K. Nishiizumi, D. J. Hillegonds, M. W. Caffee, J. Masarik Jan 2004

Unraveling The Exposure Histories Of Aubrites, K. C. Welten, K. Nishiizumi, D. J. Hillegonds, M. W. Caffee, J. Masarik

Department of Physics and Astronomy Faculty Publications

No abstract provided.

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Muonium-Antimuonium Oscillations And Massive Majorana Neutrinos, T. E. Clark, S. T. Love Jan 2004

Muonium-Antimuonium Oscillations And Massive Majorana Neutrinos, T. E. Clark, S. T. Love

Department of Physics and Astronomy Faculty Publications

The electron and muon number violating muonium-antimuonium oscillation process can proceed provided that neutrinos have nonzero masses and mix among the various generations. Modifying the Standard Model only by the inclusion of singlet right-handed neutrino fields and allowing for general neutrino masses and mixings, the leading order matrix element contributing to this process is computed. For the particularly interesting case where the neutrino masses are generated by a seesaw mechanism with a very large Majorana mass M-R much greater than M-W, it is found that both the very light and very heavy Majorana neutrinos each give comparable contributions to the …

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Solid-State Detectors: Trends, Developments, And Operational Experiences, D. Bortoletto Jan 2004

Solid-State Detectors: Trends, Developments, And Operational Experiences, D. Bortoletto

Department of Physics and Astronomy Faculty Publications

Silicon detectors are at the heart of many high-energy physics experiments. Intense research and development is taking place to improve the radiation hardness of solid-state detectors for future upgrades of the Large Hadron Collider. New integrated technologies which promise to achieve the excellent resolution needed for precision measurements of the Higgs couplings at the Linear Collider are under development. Prospects for these future projects and the experience gained in the operation and the construction of large silicon detectors will be presented. (C) 2004 Elsevier B.V. All rights reserved.

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Frequency Domain Identification Of Tip-Sample Van Der Waals Interactions In Resonant Atomic Force Microcantilevers, S. Q. Hu, S. Howell, A. Raman, R. Reifenberger, M. Franchek Jan 2004

Frequency Domain Identification Of Tip-Sample Van Der Waals Interactions In Resonant Atomic Force Microcantilevers, S. Q. Hu, S. Howell, A. Raman, R. Reifenberger, M. Franchek

Department of Physics and Astronomy Faculty Publications

Hamaker constants are characteristic material properties that determine the magnitude of the nonlinear van der Waals force between atoms, molecules and nanoscale aggregates of atoms. This paper explores the novel possibility of using Harmonic Balance based nonlinear system identification methods to extract from the nonlinear vibration spectrum Of resonant atomic force silicon microcantilevers, the Hamaker constants between a few atoms at the tip of the microcantilever and graphite, gold and silicon carbide samples. First, the nonlinear dynamics of a diving board microcantilever coupled to the samples through van der Waals force potentials are investigated through a discretized model of the …

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Trends In Nanotechnology, A. Correia, P. A. Serena, J. J. Saenz, M. Welland, R. Reifenberger Jan 2004

Trends In Nanotechnology, A. Correia, P. A. Serena, J. J. Saenz, M. Welland, R. Reifenberger

Department of Physics and Astronomy Faculty Publications

No abstract provided.

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