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The National Institute of Justice (NIJ) standard for walk-through metal detectors for use in concealed weapon detection was written in 1974. The NIJ standard has been rewritten to provide repeatable and reproducible test methods, improved detection
C. B. Vartuli, F. A. Stevie, David A. Wollman, M. Antonell, R. B. Irwin, J. M. McKinley, T L. Shofner, B. M. Purcell, S. A. Anderson, Bobby To
Cu contamination has become a larger concern as more semiconductor fabrication facilities switch from aluminum to Cu interconnects. The resolution limits of several analytical tools are compared to determine the optimum analysis methods for detecting Cu
Beginning with expressions for the vector potential, the equations for calculating the magnetic flux density from up to three rectangular loops of wire in the same plane are derived. The geometry considered is the same as that found in some walk-through
A measurement system for evaluating the performance of hand-held (HH) and walk-through (WT) metal detectors is described. These detectors produce time-varying magnetic fields that interact with objects comprised of electrically conductive and/or
S. R. Golwala, R. Abusaidi, D. S. Akerib, P. D. Barnes, D. B. Bauer, A. Bolozdynya, P. Brink, B. Cabrera, D. O. Caldwell, J. P. Castle, R. M. Clarke, P. Colling, M. B. Crisler, A. Da Silva, A. K. Davies, R. Dixon, S. Eichblatt, Kent D. Irwin, R. J. Gaitskell, E. E. Haller, J. Hellmig, Martin Huber, J. Jochum, F. P. Lipschultz, John M. Martinis, Sae Woo Nam, J. Nelson, B. Neuhauser, T. A. Perera, M. Perillo-Issac, R. R. Ross, T. Saab, B. Sadoulet, R. W. Schnee, P. Shestople, T. Shutt, Amy Smith, A. H. Sonnenschein, A. L. Spadafora, S. Yellin, B. A. Young
The Cryogenic Dark Matter Search (CDMS) employs massive ionization- and phonon-mediated detectors to search for WIMPs via their elastic scattering interactions with nuclei while discriminating against interactions by other background particles. Limits on
Numerical simulations reveal that a phase-locked loop can be operated in a chaotic regime to generate a high level of noise which is approximately white over a broad frequency range. Heuristic arguments indicate that the low-frequency power spectrum may be
Richard L. Kautz, Mark W. Keller, John M. Martinis
Leakage and counting errors are explored experimentally in a well-characterized seven-junction electron pump and compared with predictions of the orthodox theory, including cotunneling.
C Weber, Ronald H. Ono, James Booth, Leila R. Vale, Samuel Benz, A. M. Klushin, H. Kohlstedt, R. Semerad
We have investigated both conventional and meandering coplanar microwave transmission lines patterned in Y-Ba-Cu-O/Au bilayers on yttria-stablized zirconia and sapphire substrates. Within the meandering waveguides, the gentre conductor was deformed from a
H. Q. Li, Ronald H. Ono, Leila R. Vale, David A. Rudman, Sy-Hwang Liou
We have fabricated and studied a variety of devices based on stacked Yba 2Cu 3O x bicrystal Josephson junctions in a multilayer structure. The proximity of the junctions in the two layers produces a large number of effects based on interactions between the
Leila R. Vale, Ronald H. Ono, Donald G. McDonald, Robert J. Phelan
We have developed YBa 2Cu 3O 7-x (YBCO) thermometers for large-area (4 mm x 4 mm) electrical substitution bolometers. We passivated the YBCO with a thin Au layer and demonstrated a noise equivalent temperature of 4 nK Hz -1/2. We then used a resistor layer
Leila R. Vale, Ronald H. Ono, J. Talvacchio, M. G. Forrester, B. D. Hunt, M. S. DiTorio, Ki Youl Yang, S. Yoshizumi
We report on a study of long term aging in three different types of Yba 2Cu 3O 7-x Josephson junctions. Junction aging will affect the choices made in integrating this technology with actual applications. The junction types used in this study are (a) Co
Samuel Benz, Clark A. Hamilton, Charles J. Burroughs
Operating margins for biolar superconducting voltage waveform synthesizer were measured. Current ranges were determined for 101 equally spaced dc voltage steps between - 18.6 and + 18.6 mV. The measured voltages of these steps deviated from the expected
Donald G. McDonald, Robert J. Phelan, Leila R. Vale, Ronald H. Ono, David A. Rudman
We are developing Yba 2Cu 3O 7-x (YBCO) thermometers for large area bolometers that include a heater for calibration by the electrical substitution of power. Because YBCO on buffered Si is under mechanical stress and must be very thin to avoid cracking, we
James Booth, Leila R. Vale, Ronald H. Ono, John H. Claassen
We demonstrate the use of a new experimental technique based on mutual inductance measurements to quantitatively predict nonlinear effects in microwave devicesfabricated from high-temperature superconductor (HTS) materials. The mutual inductance
David A. Rudman, F. J. Stork, James Booth, J. Y. Juang, Leila R. Vale, G. J. Beatty, C. I. Williams, James A. Beall, Ronald H. Ono, S. B. Qadri, M. S. Osofsky, E. F. Skelton, John H. Claassen, G. Gibson, J. L. MacManus-Driscoll, N. Malde, L. F. Cohen
We have studied the effect of oxygen pressure (PO 2) during pulsed laser deposition on the properties of YBCO films, with particular attention to the low power microwave surface resistance R s.
James Booth, James A. Beall, David A. Rudman, Leila R. Vale, Ronald H. Ono, Christopher L. Holloway, S. B. Qadri, M. S. Osofsky, E. F. Skelton, J. H. Claasen, G. Gibson, J. L. MacManus-Driscoll, N. Malde, L. F. Cohen
We present results of a systematic study of the effect of film deposition temperture on both the linear and nonlinear response of super-conducting Yba 2Cu 3O7-γ^ (YBCO) thin films and devices at microwave frequencies. Measurements of the unpatterned films
A. H. Miklich, J. X. Przybysz, T. J. Smith, Samuel Benz, Todd E. Harvey
We describe the use of thin-film superconducting transformers at frequencies up to 20 GHz. Transformers with turns ratios of 2,3, and 7 were fabricated out of Nb and tested in a liquid-He Dewar. The measured S-parameters showed considerably less bandwidth