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1. MR imaging of flow through tortuous vessels: A numerical simulation

Author: Liang Der Jou, David Saloner, S. Berger, and R van Tyen
Subjects: Carotid Artery, Common, Quantitative Biology::Tissues and Organs, Physics::Medical Physics, Blood Pressure, Magnetic resonance angiography, Displacement (vector), Magnetics, Nuclear magnetic resonance, medicine, Humans, Computer Simulation, Radiology, Nuclear Medicine and imaging, Streamlines, streaklines, and pathlines, Physics, medicine.diagnostic_test, Computer simulation, Models, Cardiovascular, Pulse sequence, Blood flow, Mechanics, Blood Viscosity, Image Enhancement, Magnetic Resonance Imaging, Carotid Arteries, Flow (mathematics), Regional Blood Flow, Computer Science::Computer Vision and Pattern Recognition, Carotid Artery, External, Angiography, Rheology, Algorithms, Blood Flow Velocity, Carotid Artery, Internal
Abstract: A novel computer simulation technique is presented that allows the calculation of images from Magnetic Resonance Angiography (MRA) studies of blood flow in realistic curving and branching two-dimensional vessel geometries. Fluid dynamic calculations provide flow streamlines through curved or branching vessels. MR simulations generate images for specific MR pulse sequence parameters. Simulations of steady flow in carotid bifurcation and carotid siphon geometries as imaged by a standard, flow-compensated, spoiled gradient echo sequence illustrate the major features seen in clinical time of flight MRA studies. The simulations provide insight into a number of artifacts encountered in MRA such as displacement artifacts, signal pile-up, truncation artifacts, and intravoxel phase dispersion.
Published: 1994
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2. Evaluation of myocardial perfusion abnormalities with gadolinium-enhanced snapshot MR imaging in humans. Work in progress

Author: R van Tyen, David Saloner, and Saul Schaefer
Subjects: Adult, Gadolinium DTPA, medicine.medical_specialty, Gadolinium, Ischemia, Contrast Media, chemistry.chemical_element, Coronary Disease, Coronary Angiography, Coronary artery disease, Meglumine, Coronary Circulation, Internal medicine, Organometallic Compounds, Humans, Medicine, Radiology, Nuclear Medicine and imaging, In patient, Radionuclide Imaging, Aged, medicine.diagnostic_test, business.industry, Magnetic resonance imaging, Dipyridamole, Middle Aged, Pentetic Acid, medicine.disease, Magnetic Resonance Imaging, Mr imaging, Drug Combinations, Thallium Radioisotopes, chemistry, Exercise Test, Cardiology, business, Nuclear medicine, Perfusion, medicine.drug
Abstract: To determine whether myocardial perfusion abnormalities could be detected in patients with coronary artery disease by means of contrast material-enhanced magnetic resonance (MR) images, a snapshot imaging technique was used in six patients with coronary artery disease and four healthy subjects in conjunction with pharmacologic stress (dipyridamole infusion) and bolus injection of gadopentetate dimeglumine. MR images from all patients and healthy subjects were quantitatively analyzed to define spatial changes in signal intensity after administration of dipyridamole and gadopentetate dimeglumine. The resultant findings were compared with findings on thallium-201 scintigrams obtained after administration of dipyridamole and on coronary arteriograms in all patients. Nine myocardial regions supplied by stenosed arteries showed diminished levels of signal intensity after infusion of the contrast agent compared with those of normally perfused regions. These findings were in agreement with those obtained with T1-201 scintigraphy (in eight of nine regions) and arteriography. Thus, contrast-enhanced high-speed MR imaging with use of dipyridamole enabled detection of regional perfusion abnormalities in humans.
Published: 1992
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3. Test of spin dependence in charm-quark fragmentation to D*

Author: K. A. Schwitkis, R. W. Stephens, Ronald R. Ross, W. Vernon, M. T. Ronan, B. C. Shen, W. A. Wenzel, T. K. Edberg, D. J. Lambert, M. Pripstein, W. T. Lin, Allan G Clark, J. S. Steinman, K. H. Fairfield, R. R. Kofler, M. L. Stevenson, A. Fridman, S. K. Park, Robert W. Kenney, T. Kamae, S. Khacheryan, A. P.T. Palounek, D. A. Crane, J. M. Hauptman, C. D. Buchanan, H. P. Paar, A. Bay, S. J. Yellin, N. A. Nicol, J. J. Eastman, G. D. Cowan, F. R. Rouse, H. Marsiske, G. Zapalac, A. Lu, Philippe Eberhard, S. J. Maxfield, Hiroaki Aihara, C. Ho, S. Toutounchi, Margaret Alston-Garnjost, Elliott D. Bloom, Y. T. Oyang, R. van Tyen, H. Y. Chao, C. Zeitlin, A. R. Barker, S. C. Loken, S. B. Chun, E. S. Miller, G. Lynch, J. G. Layter, R. E. Avery, H. Yamamoto, K. A. Derby, P. J. Oddone, B. D. Magnuson, Werner Hofmann, E. M. Wang, M. G. Strauss, H. Oh, J. Lys, R. J. Madaras, F.L. Linde, H. H. Bingham, J. C. Sens, D. R. Nygren, D. O. Caldwell, Tadayuki Takahashi, George P Yost, Orin I. Dahl, M. Daoudi, R. Belcinski, G. Masek, Y. X. Wang, D. H. Stork, Z. R. Wolf, Willem G. J. Langeveld, G. Shapiro, A. M. Eisner, D. E. Pellett, G. J. VanDalen, F. C. Erné, D. A. Bauer, G. Godfrey, M. K. Sullivan, J. R. Smith, L. G. Mathis, and IHEF (IoP, FNWI)
Subjects: Quark, Physics, Density matrix, Particle physics, Annihilation, Time projection chamber, Computer Science::Information Retrieval, Elementary particle, Fermion, Helicity, Charm quark, Nuclear physics, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, High Energy Physics::Experiment
Abstract: We have measured the polarization of {ital D}{sup *}, the energy dependence of the polarization, and the spin-density matrix of {ital D}{sup *} in {ital e}{sup +}{ital e{minus}} annihilation at a center-of-mass energy of 29 GeV using the Time Projection Chamber detector at the SLAC storage ring PEP. In 147 pb{sup {minus}1} of data we see no strong evidence for polarization, alignment, or final-state interactions in this fragmentation process.
Published: 1991

4. Measurement of the total hadronic cross section in taggedγγreactions

Author: N. A. Nicol, Orin I. Dahl, F. R. Rouse, J. G. Layter, J. J. Eastman, R. Belcinski, S. Toutounchi, G. Masek, Robert W. Kenney, D. H. Stork, C. Ho, M. K. Sullivan, L. G. Mathis, C. Zeitlin, H. Aihara, Philippe Eberhard, A. R. Clark, S. J. Maxfield, R. E. Avery, M. G. Strauss, S. K. Park, T. Kamae, E. M. Wang, T. K. Edberg, S. C. Loken, William A. Wenzel, Z. R. Wolf, W. Vernon, M. Pripstein, Willem G. J. Langeveld, J. S. Steinman, K. A. Derby, M. T. Ronan, M. L. Stevenson, Werner Hofmann, P. J. Oddone, W. T. Lin, W. Wagner, D. A. Bauer, R. R. McNeil, George P Yost, Y. T. Oyang, D. E. Pellett, Tadayuki Takahashi, G. Godfrey, J. Lys, A. Fridman, M. Daoudi, R. R. Kofler, H. Yamamoto, B. D. Magnuson, H. Oh, D. R. Nygren, J. C. Sens, H. H. Bingham, Gilbert Shapiro, D. O. Caldwell, S. Khacheryan, S. J. Yellin, J. R. Smith, S. B. Chun, R. W. Stephens, G. Lynch, F. C. Erné, A. M. Eisner, Ronald R. Ross, K. H. Fairfield, H. P. Paar, G. J. VanDalen, J. M. Hauptman, C. D. Buchanan, K. A. Schwitkis, H. Marsiske, A. P.T. Palounek, G. D. Cowan, A. Bay, D. J. Lambert, G. Zapalac, Margaret Alston-Garnjost, R. van Tyen, A. R. Barker, H. Y. Chao, D. A. Crane, F.L. Linde, R. J. Madaras, B. C. Shen, A. Lu, Elliott D. Bloom, Y. X. Wang, and E. S. Miller
Subjects: Physics, Quantum chromodynamics, Nuclear physics, Particle physics, Photon, Scattering, Hadron, Elementary particle, Parton, Fermion, Energy (signal processing)
Abstract: We present a measurement of the total cross section for {gamma}{gamma}{r arrow}hadrons, with one photon quasireal and the other a spacelike photon of mass squared {minus}{ital Q}{sup 2}. Results are presented as a function of {ital Q}{sup 2} and the {gamma}{gamma} center-of-mass energy {ital W}, with the {ital Q}{sup 2} range extending from 0.2 to 60 GeV{sup 2}, and {ital W} in the range from 2 to 10 GeV. The data were taken with the TPC/Two-Gamma facility at the SLAC {ital e}{sup +}{ital e}{sup {minus}} storage ring PEP, which was operated at a beam energy of 14.5 GeV. The cross section exhibits a gentle falloff with increasing {ital W}. Its {ital Q}{sup 2} dependence is shown to be well described by an incoherent sum of vector-meson and pointlike scattering over most of the observed {ital W} range. Agreement at high {ital Q}{sup 2} is improved if a minimum-{ital p}{sub {ital T}} cutoff (motivated by QCD) is imposed on the pointlike contribution.
Published: 1990
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5. Calculation of the magnetization distribution for fluid flow in curved vessels

Author: L D, Jou, R, van Tyen, S A, Berger, and D, Saloner
Subjects: Carotid Arteries, Phantoms, Imaging, Pulsatile Flow, Image Processing, Computer-Assisted, Models, Cardiovascular, Humans, Computer Simulation, Blood Flow Velocity, Magnetic Resonance Angiography
Abstract: The signal intensity in magnetic resonance angiography (MRA) images reflects both morphological and flow-related features of vascular anatomy. A thorough understanding of MRA, therefore, demands a careful analysis of flow-related effects. Computational fluid dynamics (CFD) methods are very powerful in determining flow patterns in 3D tortuous vessels for both steady and unsteady flow. Previous simulations of MRA images calculated the magnetization of flowing blood by tracking particles as they moved along flow streamlines that had been determined by a CFD calculation. This manuscript describes MRA simulations that use CFD calculations to determine magnetization variation at a fixed point and, therefore, do not require streamline tracking to calculate the distribution of magnetization in flowing fluids. This method inherently accounts for uniform particle density, avoids problems associated with tracking particles close to the wall, and is well-suited to modeling pulsatile flow.
Published: 1996

6. Central intraluminal saturation stripe on MR angiograms of curved vessels: simulation, phantom, and clinical analysis

Author: Liang Der Jou, Stanley A. Berger, William P. Dillon, David Saloner, and R van Tyen
Subjects: Adult, Male, Imaging phantom, Nuclear magnetic resonance, medicine, Humans, Radiology, Nuclear Medicine and imaging, Computer Simulation, medicine.diagnostic_test, business.industry, Phantoms, Imaging, Laminar flow, Magnetic resonance imaging, Middle Aged, Secondary flow, Transverse plane, medicine.anatomical_structure, Angiography, cardiovascular system, Blood Vessels, Female, Saturation (chemistry), business, Artifacts, Blood Flow Velocity, Carotid Artery, Internal, Magnetic Resonance Angiography, Blood vessel
Abstract: PURPOSE: To investigate the appearance of reduced signal intensity in the center of blood vessels on magnetic resonance (MR) angiograms that can mimic intraluminal thrombus. MATERIALS AND METHODS: Simulations and phantom studies were performed to analyze MR angiogram appearance distal to a pronounced curve. RESULTS: Saturation effects substantially lower the signal strength in the center of the vessel relative to that at the vessel periphery. These effects appeared even though the flow was well ordered and laminar. In curved geometries, secondary flow patterns produced counter-rotating vortices, which moved the fastest-moving particles to the outside of the curve and folded the slow-moving particles to the center of the vessel. CONCLUSION: Imaging parameter choices that reduce saturation, such as acquisition of a two-dimensional section transverse to the vessel and through the questionable region, effectively eliminate the central hypointensity effect in vivo.
Published: 1996

7. Study ofη’formation in photon-photon collisions

Author: H. Aihara, M. Alston-Garnjost, R. E. Avery, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, D. A. Bauer, H. -U. Bengtsson, D. L. Bintinger, G. J. Bobbink, T. S. Bolognese, A. D. Bross, C. D. Buchanan, A. Buijs, D. O. Caldwell, A. R. Clark, G. D. Cowan, D. A. Crane, O. I. Dahl, K. A. Derby, J. J. Eastman, P. H. Eberhard, T. K. Edberg, A. M. Eisner, R. Enomoto, F. C. Erné, T. Fujii, J. W. Gary, W. Gorn, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X-Q. Lu, G. R. Lynch, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, G. E. Masek, L. G. Mathis, J. A. J. Matthews, S. J. Maxfield, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Park, S. K. Park, D. E. Pellett, M. Pripstein, M. T. Ronan, R. R. Ross, F. R. Rouse, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, J. S. Steinman, M. L. Stevenson, D. H. Stork, M. G. Strauss, M. K. Sullivan, T. Takahashi, J. R. Thompson, N. Toge, S. Toutounchi, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, Z. R. Wolf, H. Yamamoto, S. J. Yellin, C. Zeitlin, and W-M. Zhang
Subjects: Physics, Nuclear physics, Particle physics, Photon, Prime (order theory)
Published: 1987
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8. Study of Bose-Einstein correlations ine+e−annihilation at 29 GeV

Author: H. K. Ticho, L. T. Kerth, Em Wang, D. R. Nygren, G. R. Lynch, W. A. Wenzel, W. E. Slater, A. R. Clark, X. Q. Lu, M. Yamauchi, F. R. Rouse, L. Madansky, M. L. Stevenson, N. Toge, A. D. Bross, R. W. Kenney, J. Hylen, W. M. Zhang, D. L. Fancher, J. M. Hauptman, C. Y. Chien, R. I. Koda, M. Pripstein, S. C. Loken, K. Maruyama, R. R. Kofler, A. Cordier, M. Alston-Garnjost, C. S. Lindsey, M. D. Shapiro, R. F. van Daalen Wetters, Hirotsugu Fujii, O. Chamberlain, K. A. Derby, H. Yamamoto, M. R. Wayne, A. V. Barnes, R. R. Sauerwein, M. T. Ronan, R. van Tyen, A. Pevsner, B. A. Barnett, G. J. Vandalen, W. Gorn, S. O. Melnikoff, A. Barbaro-Galtieri, R. J. Madaras, J. N. Marx, K. K. Kwong, T. Fujii, B. J. Blumenfeld, J. G. Layter, W. Moses, H. S. Kaye, O. I. Dahl, Tuneyoshi Kamae, H. U. Bengtsson, Hiroaki Aihara, C. D. Buchanan, C. T. Day, J. E. Huth, W. Hofmann, R. R. Ross, P. J. Oddone, D. H. Stork, B. Gabioud, D. A. Park, G. Shapiro, J. A. Bakken, P. H. Eberhard, J. W. Gary, B. C. Shen, P. R. Robrish, N. J. Hadley, Peter Nemethy, and J. A J Matthews
Subjects: Physics, Particle physics, Time projection chamber, Annihilation, Meson, Hadron, Bose–Einstein correlations, Nuclear physics, symbols.namesake, Pion, Pair production, Bose–Einstein statistics, symbols, High Energy Physics::Experiment, Nuclear Experiment
Abstract: Bose-Einstein correlations between like-sign pions have been investigated in e/sup +/e/sup -/ annihilation at ..sqrt..s = 29 GeV using the Time Projection Chamber detector at the SLAC e/sup +/e/sup -/ storage ring PEP. The production rate of like-sign pion pairs with small relative momentum is found to be increased by more than 50% over the rate expected for uncorrelated production of pions. From the correlation length, a typical source radius of 0.65 fm is derived. Data are consistent with a spherical shape of the pion source. No dependence of radius or correlation strength on the event multiplicity is observed.
Published: 1985
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9. Search for Charge-43eParticles Produced ine+e−Annihilations

Author: M. Urban, A. V. Barnes, Hirotsugu Fujii, D. A. Park, W. E. Slater, P. R. Robrish, D. H. Stork, R. R. Sauerwein, B. A. Barnett, B. C. Shen, S. O. Melnikoff, W. Gorn, K. A. Derby, J. G. Layter, Peter Nemethy, R. W. Kenney, P. Delpierre, M. E. Zeller, J. A. J. Matthews, A. Barbaro-Galtieri, J. N. Marx, J. Hylen, W. M. Zhang, Barry Blumenfeld, M. T. Ronan, R. R. Kofler, G. R. Lynch, C. D. Buchanan, Mitchell Wayne, W. X. Gu, J. A. Bakken, K. K. Kwong, H. J. Hilke, H. Aihara, Orin I. Dahl, M. Pripstein, K. Maruyama, C. Y. Chien, G. W. London, X. Q. Lu, W.A. Wenzel, Gilbert Shapiro, C. Q. Chen, Werner Hofmann, H. K. Ticho, M. L. Stevenson, R. M. Majka, J. E. Huth, P. J. Oddone, C. T. Day, D. R. Nygren, M. Yamauchi, R. R. Ross, J. M. Hauptman, J. Mallet, R. J. Madaras, T. Kamae, Toshitsugu Fujii, A. D. Bross, Nicholas John Hadley, A. Pevsner, Margaret Alston-Garnjost, R. van Tyen, Owen Chamberlain, D. L. Fancher, G. J. Van Dalen, J. Chiba, W. Moses, N. Toge, J. W. Gary, C. S. Lindsey, L. Madansky, R. I. Koda, H. Videau, Marjorie Shapiro, F. R. Rouse, R. F. van Daalen Wetters, L. T. Kerth, A. R. Clark, D. H. Badtke, William Carithers, B. Gabioud, P. S. Martin, H. Iwasaki, Philippe Eberhard, and S. C. Loken
Subjects: Nuclear physics, Physics, General Physics and Astronomy, Charge (physics)
Published: 1984
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10. Geiger Mode Calorimeter for PEP-4

Author: H. Aihara, M. Alston-Garnjost, D. H. Badtke, J. A. Bakken, A. Barbaro-Galtieri, A. V. Barnes, B. A. Barnett, B. Blumenfeld, A. Bross, C. D. Buchanan, W. C. Carithers, O. Chamberlain, J. Chiba, C-Y. Chien, A. R. Clark, O. I. Dahl, C. T. Day, P. Delpierre, K. A. Derby, P. H. Eberhard, D. L. Fancher, H. Fujii, T. Fujii, B. Gabioud, J. W. Gary, W. Gorn, N. J. Hadley, J. M. Hauptman, B. Heck, H. Hilke, J. E. Huth, J. Hylen, H. Iwasaki, T. Kamae, R. W. Kenney, L. T. Kerth, R. Koda, R. R. Kofler, K. K. Kwong, J. G. Layter, C.S Lindsey, S. C. Loken, X-Q. Lu, G. R. Lynch, L. Madansky, R. J. Madaras, R. Majka, J. Mallet, P. S. Martin, K. Maruyama, J. N. Marx, J. A. J. Matthews, S. O. Melnikoff, W. Moses, P. Nemethy, D. R. Nygren, P. J. Oddonel, D. Park, A. Pevsner, M. Pripstein, P. R. Robrish, M. T. Ronan, R. R. Ross, F. R. Rouse, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, M. L. Stevenson, D. H. Stork, H. K. Ticho, N. Toge, M. Urban, G. J. Van Dalen, R. van Tyen, H. Videau, M. Wayne, W. A. Wenzel, R. F. vanDaalen Wetters, M. Yamauchi, M. E. Zeller, and W-M. Zhang
Subjects: Physics, Nuclear and High Energy Physics, Photon, Calorimeter (particle physics), Physics::Instrumentation and Detectors, business.industry, STRIPS, Particle detector, Cathode, law.invention, Optics, Nuclear Energy and Engineering, law, Measuring instrument, Calibration, Geiger counter, Electrical and Electronic Engineering, business
Abstract: The PEP-4 hexagonal barrel calorimeter, with lead-laminate layers and 5×lOmm2 Geiger-mode discharge cells, has demonstrated excellent stability and uniformity in operation. The use of projective geometry in half degree-wide cathode strips at ±60 degrees to the sense wire channels provides excellent spatial resolution and reconstruction capability. The electronic noise-to-signal ratio without preamplification is sufficiently low that individual 50 pC Geiger discharges are accurately measured and used for energy calibration. Measurements made at 14.5 GeV e± beam energy have provided preliminary spectra of Bhabhas and of photon-photon invariant mass. The latter show that ?o's can be reconstructed.
Published: 1983
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11. Exclusive Production ofK+K−π+π−in Photon-Photon Collisions

Author: H. Aihara, M. Alston-Garnjost, J. C. Armitage, J. A. Bakken, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, H. -U. Bengtsson, D. L. Bintinger, B. J. Blumenfeld, G. J. Bobbink, A. D. Bross, C. D. Buchanan, A. Buijs, M. P. Cain, D. O. Caldwell, O. Chamberlain, C. -Y. Chien, A. R. Clark, A. Cordier, O. I. Dahl, C. T. Day, K. A. Derby, M. A. van Driel, P. H. Eberhard, A. M. Eisner, F. C. Erne, D. L. Fancher, H. Fujii, T. Fujii, B. Gabioud, J. W. Gary, W. Gorn, N. J. Hadley, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, U. P. Joshi, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X. -Q. Lu, G. R. Lynch, L. Madansky, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, K. Maruyama, G. E. Masek, J. A. J. Matthews, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Palmer, D. A. Park, D. E. Pellett, A. Pevsner, M. Pripstein, P. R. Robrish, M. T. Ronan, R. R. Ross, F. R. Rouse, R. R. Sauerwein, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, M. L. Stevenson, D. H. Stork, M. K. Sullivan, J. R. Thompson, H. K. Ticho, J. Timmer, N. Toge, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, H. Yamamoto, M. Yamauchi, S. J. Yellin, and W. -M. Zhang
Subjects: Physics, Nuclear physics, Pair production, Pion, Annihilation, Meson, Branching fraction, Hadron, Mass spectrum, General Physics and Astronomy, Particle identification
Abstract: We report a measurement of the reaction ..gamma gamma -->..K/sup +/K/sup -/..pi../sup +/..pi../sup -/ in both tagged and untagged events at PEP. The cross section rises with invariant ..gamma gamma.. mass to about 15 nb at 2 GeV and falls slowly at higher masses. We find clear evidence for the processes ..gamma gamma -->..phi..pi../sup +/..pi../sup -/ and ..gamma gamma -->..K/sup asterisk0/(892)K..pi... Upper limits (95% C.L.) of 1.5 and 5.7 nb in the mass range from 1.7 to 3.7 GeV are obtained for phirho/sup 0/ and K/sup asterisk0/K/sup asterisk0/ production, respectively.
Published: 1985
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12. K*0andKS0Meson Production ine+e−Annihilations at 29 GeV

Author: J. M. Hauptman, A. Barbaro-Galtieri, B. Gabioud, B. C. Shen, L. Madansky, W.A. Wenzel, J. E. Huth, J. Hylen, H. Yamamoto, W. Moses, C. S. Lindsey, Gilbert Shapiro, R. I. Koda, M. L. Stevenson, S. C. Loken, T. Kamae, G. J. VanDalen, K. A. Derby, W. M. Zhang, F. R. Rouse, Q. Chamberlain, A. Cordier, A. Pevsner, Hirotsugu Fujii, D. A. Park, R. R. Kofler, Peter Nemethy, Philippe Eberhard, G. R. Lynch, Toshitsugu Fujii, N. Toge, Marjorie Shapiro, Orin I. Dahl, R. F. van Daalen Wetters, C. Y. Chien, Nicholas John Hadley, M. T. Ronan, E. M. Wang, M. Yamauchi, Hiroaki Aihara, Werner Hofmann, B. A. Barnett, L. T. Kerth, J. W. Gary, K. K. Kwong, Margaret Alston-Garnjost, R. van Tyen, A. D. Bross, W. E. Slater, Mitchell Wayne, A. R. Clark, A. V. Barnes, D. L. Fancher, D. H. Stork, P. J. Oddone, R. R. Sauerwein, J. G. Layter, K. Maruyama, R. R. Ross, H. K. Ticho, R. J. Madaras, J. A. Bakken, W. Gorn, H. S. Kaye, Barry Blumenfeld, C. D. Buchanan, C. T. Day, P. R. Robrish, J. N. Marx, X. Q. Lu, D. R. Nygren, J. A. J. Matthews, M. Pripstein, S. O. Melnikoff, and R. W. Kenney
Subjects: Nuclear physics, Physics, Particle physics, Antiparticle, Annihilation, Pion, Meson, Antimatter, Electron–positron annihilation, Hadron, General Physics and Astronomy, Elementary particle
Abstract: The inclusive production cross sections and transverse momentum distributions of ${K}^{*0}$ and ${{K}_{S}}^{0}$ mesons in ${e}^{+}{e}^{\ensuremath{-}}$ annihilation at a center-of-mass energy of 29 GeV have been measured by means of the time projection chamber detector in the PEP-4 experiment. The mean multiplicites are found to be 0.49 \ifmmode\pm\else\textpm\fi{} 0.04(stat.) \ifmmode\pm\else\textpm\fi{} 0.07(syst.) (${K}^{*0}+{\stackrel{-}{K}}^{*0}$) and 1.22 \ifmmode\pm\else\textpm\fi{} 0.03(stat.) \ifmmode\pm\else\textpm\fi{}0.15(syst.) (${K}^{0}+{\stackrel{-}{K}}^{0}$) per event.
Published: 1984
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13. A Muon Detection System for the PEP4 Facility

Author: Hirotsugu Fujii, B. C. Shen, D. A. Park, O. Chamberlain, W. E. Slater, A. Barbaro-Galtieri, G. Lynch, T. Kamae, C. S. Lindsey, W. Gorn, M. L. Stevenson, X-Q. Lu, K. K. Kwong, William A. Wenzel, J. A. Bakken, J. W. Gary, C. D. Buchanan, R. R. Kofler, D. H. Badtke, R. W. Kenney, Orin I. Dahl, J. Mallet, G. J. Van Dalen, Allan G Clark, J. N. Marx, M. Yamauchi, K. A. Derby, H. Hilke, J. Chiba, Marjorie Shapiro, J. M. Hauptman, W. Moses, R. van Tyen, A. D. Bross, H. Iwasaki, L. Madansky, P. S. Martin, J. Hylen, Ronald R. Ross, J. E. Huth, W-M. Zhang, Hiroaki Aihara, R. I. Koda, N. Toge, M. Alston-Garnjost, R. J. Madaras, F. R. Rouse, L. T. Kerth, D. H. Stork, D. L. Fancher, B. Heck, C. T. Day, H. Videau, W. J. Spangler, N. J. Hadley, J. G. Layter, R. Majka, R. F. vanDaalen Wetters, S. C. Loken, W. C. Carithers, M. E. Zeller, P. H. Eberhard, B. Gabioud, P. Delpiee, Mitchell Wayne, P. J. Oddone, A. V. Barnes, J. A. J. Matthews, P. Nemethy, M. T. Ronan, P. R. Robrish, M. Pripstein, C.Y. Chien, G. Shapiro, S. O. Melnikoff, K. Maruyama, H. K. Ticho, A. Pevsner, Barry Blumenfeld, D. R. Nygren, B. A. Barnett, and T. Fujii
Subjects: Physics, Nuclear and High Energy Physics, Muon, business.industry, Detector, Particle detector, Linear particle accelerator, Nuclear physics, Software, Nuclear Energy and Engineering, Measuring instrument, Electrical and Electronic Engineering, business, Computer hardware
Abstract: A large muon detection system has been constructed and is fully operational in the PEP 4 facility. It is more than 99.6% efficient. The system is rugged and reliable. It is possible to verify the integrity of all the chambers in a few minutes. Associated software for identifying muons has been written and is working.
Published: 1983
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14. Performance of a Drift Chamber System for the Time Projection Chamber Detector Facility at PEP

Author: B. A. Barnett, J. Mallet, A. Barbaro-Galtieri, M. E. Zeller, M. Urban, P. S. Martin, A. D. Bross, Mitchell Wayne, Ronald R. Ross, W-M. Zhang, L. Madansky, R. Majka, N. Toge, G. J. Van Dalen, R. I. Koda, H. Videau, M. Pripstein, J. G. Layter, J. M. Hauptman, R. J. Madaras, R. F. vanDaalen Wetters, K. Maruyama, C.Y. Chien, N. J. Hadley, B. Gabioud, A. V. Barnes, P. J. Oddone, D. R. Nygren, J. A. J. Matthews, M. T. Ronan, M. Yamauchi, P. R. Robrish, G. Shapiro, R. R. Kofler, R. van Tyen, Marjorie Shapiro, W. Moses, F. R. Rouse, B. C. Shen, Orin I. Dahl, W. Gorn, H. K. Ticho, P. Nemethy, S. O. Melnikoff, S. C. Loken, Hirotsugu Fujii, H. Iwasaki, Clark S. Lindsey, J. Chiba, D. A. Park, O. Chamberlain, William A. Wenzel, C. S. Lindsey, W. C. Carithers, L. T. Kerth, H-J. Hilke, Allan G Clark, C. D. Buchanan, J. Hylen, P. H. Eberhard, Hiroaki Aihara, G. Lynch, T. Kamae, J. A. Bakken, B. Heck, C. T. Day, P. Delpierre, T. Ftjii, M. L. Stevenson, X-Q. Lu, D. H. Stork, D. H. Badtke, A. Pevsner, R. W. Kenney, W. E. Slater, Barry Blumenfeld, K. A. Derby, J. W. Gary, J. E. Huth, M. Alston-Garnjost, D. L. Fancher, J. N. Marx, and K. K. Kwong
Subjects: Physics, Nuclear and High Energy Physics, Signal generator, Time projection chamber, Physics::Instrumentation and Detectors, business.industry, Detector, Cosmic ray, Tracking (particle physics), Particle detector, Nuclear physics, Momentum, Optics, Nuclear Energy and Engineering, Measuring instrument, Electrical and Electronic Engineering, business
Abstract: A svstem of two cylindrical drift chambers has been designed and constructed to trigger the Time Projection Chamber and to assist in tracking and momentum reconstruction. Performance of these chambers has been studied with data collected from cosmic rays and actual e+e-collisions during recent experimental runs.
Published: 1983
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15. Prompt muon production ine+e−annihilations at 29 GeV

Author: R. I. Koda, C. T. Day, J. E. Huth, D. R. Nygren, P. J. Oddone, M. Pripstein, H. U. Bengtsson, A. Cordier, D. H. Stork, B. Gabioud, J. A. Bakken, Hiroaki Aihara, A. Pevsner, G. R. Lynch, C. S. Lindsey, K. A. Derby, H. Yamamoto, B. A. Barnett, D. A. Park, L. T. Kerth, R. R. Sauerwein, R. R. Ross, Tuneyoshi Kamae, J. W. Gary, M. Yamauchi, P. R. Robrish, W. E. Slater, D. H. Badtke, O. Chamberlain, R. J. Madaras, J. N. Marx, Em Wang, B. C. Shen, A. Barbaro-Galtieri, W. Moses, F. R. Rouse, W. M. Zhang, Peter Nemethy, O. I. Dahl, L. Madansky, R. F. van Daalen Wetters, M. Alston-Garnjost, J. Hylen, R. W. Kenney, H. K. Ticho, A. R. Clark, X. Q. Lu, W. A. Wenzel, Hirotsugu Fujii, A. V. Barnes, N. Toge, A. D. Bross, M. T. Ronan, J. G. Layter, M. R. Wayne, G. J. Vandalen, W. Gorn, W. Hofmann, S. O. Melnikoff, C. Y. Chien, M. D. Shapiro, G. Shapiro, P. H. Eberhard, J. M. Hauptman, D. L. Fancher, N. J. Hadley, K. K. Kwong, T. Fujii, J. A J Matthews, B. J. Blumenfeld, S. C. Loken, K. Maruyama, R. R. Kofler, R. van Tyen, M. L. Stevenson, H. S. Kaye, and C. D. Buchanan
Subjects: Nuclear physics, Quark, Physics, Particle physics, Muon, Annihilation, Hadron, Bottom quark, Charm quark
Abstract: We have studied the production of prompt muons in hadronic events from ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$ annihilation at a center-of-mass energy of 29 GeV with the PEP4-TPC (Time Projection Chamber) detector. The muon p and ${p}_{t}$ distributions are well described by a combination of bottom- and charm-quark decays, with fitted semimuonic branching fractions of (15.2\ifmmode\pm\else\textpm\fi{}1.9\ifmmode\pm\else\textpm\fi{}1.2)% and (6.9\ifmmode\pm\else\textpm\fi{}1.1\ifmmode\pm\else\textpm\fi{}1.1)%, respectively. The muon spectra imply hard fragmentation functions for both b and c quarks, with 〈z(b quark)〉=0.80\ifmmode\pm\else\textpm\fi{}0.05\ifmmode\pm\else\textpm\fi{}0.05 and 〈z(c quark)〉=0.60\ifmmode\pm\else\textpm\fi{}0.06\ifmmode\pm\else\textpm\fi{}0.04. We derive neutral-current axial-vector couplings of a(b quark)=-0.9\ifmmode\pm\else\textpm\fi{}1.1\ifmmode\pm\else\textpm\fi{}0.3 and a(c quark)=1.5\ifmmode\pm\else\textpm\fi{}1.5\ifmmode\pm\else\textpm\fi{}0.5 from the forward-backward asymmetries.
Published: 1985
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16. Study of baryon correlations ine+e−annihilation at 29 GeV

Author: A. Lu, Peter Nemethy, J. S. Steinman, J. E. Huth, B. C. Shen, S. Toutounchi, T. Kamae, L. Mathis, R. R. McNeil, A. Barbaro-Galtieri, R. R. van Daalen Wetters, B. A. Barnett, R. Lander, Kaori Maeshima, C. D. Buchanan, S. C. Loken, E. M. Wang, D. E. Pellet, Margaret Alston-Garnjost, R. van Tyen, W. G.J. Langeveld, H. U. Bengtsson, B. van Uitert, G. E. Masek, E. S. Miller, X. Q. Lu, K. A. Schwitkis, H. Yamamoto, S. O. Melnikoff, Hiroaki Aihara, J. N. Marx, R. I. Koda, J. Hylen, N. Toge, S. J. Yellin, S. J. Maxfield, C. Zeitlin, F. R. Rouse, C. S. Lindsey, K. A. Derby, R. W. Kenney, J. T. White, J. C. Sens, D. O. Caldwell, W. Vernon, M. S. C. Williams, Z. R. Wolf, G. Cowan, Mitchell Wayne, J. Thompson, Marjorie Shapiro, W. Moses, G. J. VanDalen, B. D. Magnuson, J. W. Gary, D. A. Park, Toshitsugu Fujii, Philippe Eberhard, H. S. Kaye, T. K. Edberg, G. R. Lynch, Y. X. Wang, Tadayuki Takahashi, Ryoji Enomoto, W. E. Slater, M. G. Strauss, A. Buijs, P. J. Oddone, F.L. Linde, Werner Hofmann, R.E. Avery, R. R. Ross, T. Bolognese, H. P. Paar, R. J. Madaras, D. A. Crane, W. Gorn, S. K. Park, J. J. Eastman, W.A. Wenzel, Gilbert Shapiro, M. L. Stevenson, M. T. Ronan, K. K. Kwong, M. Pripstein, J. A. J. Matthews, M. K. Sullivan, A. D. Bross, A.R. Barker, J. R. Smith, K. H. Kees, D. R. Nygren, J. M. Hauptman, W. M. Zhang, R. R. Kofler, F. C. Erné, A. M. Eisner, Winston Ko, G. J. Bobbink, Orin I. Dahl, D. L. Bintinger, Wolfgang Wagner, A. R. Clark, D.A. Bauer, L. T. Kerth, A. V. Barnes, D. H. Stork, and J. G. Layter
Subjects: Baryon, Nuclear physics, Physics, Particle physics, Annihilation, Electron–positron annihilation, General Physics and Astronomy
Published: 1986
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17. Exclusive production ofpp¯π+π−in photon-photon collisions

Author: T. K. Edberg, H. Y. Chao, K. A. Derby, W. T. Lin, M. K. Sullivan, S. K. Park, T. Kamae, E. S. Miller, J. J. Eastman, S. Toutounchi, S. Khacheryan, H. S. Kaye, J. A. J. Matthews, Robert W. Kenney, J. C. Sens, F.L. Linde, D. O. Caldwell, A. Bay, J. G. Layter, G. D. Cowan, C. D. Buchanan, M. G. Strauss, D. A. Crane, C. Zeitlin, H. P. Paar, K. A. Schwitkis, D. E. Pellett, W. Moses, Y. X. Wang, J. M. Hauptman, M. Pripstein, Angela Barbaro-Galtieri, F. C. Erné, Margaret Alston-Garnjost, R. van Tyen, A. M. Eisner, M. Daoudi, R. E. Avery, Ronald R. Ross, Orin I. Dahl, Tadayuki Takahashi, B. C. Shen, Z. R. Wolf, E. M. Wang, Willem G. J. Langeveld, J. Hylen, G. Masek, F. R. Rouse, H. Yamamoto, J. R. Smith, S. J. Yellin, A. R. Barker, R. W. Stephens, S. C. Loken, R. J. Madaras, D. H. Stork, A. R. Clark, M. L. Stevenson, Gilbert Shapiro, D. A. Bauer, W. Wagner, G. J. Bobbink, J. S. Steinman, Werner Hofmann, William A. Wenzel, L. G. Mathis, K. H. Fairfield, H. Aihara, P. J. Oddone, B. A. Barnett, R. R. Kofler, S. B. Chun, G. Lynch, B. D. Magnuson, D. R. Nygren, Philippe Eberhard, S. J. Maxfield, A. Buijs, W. Vernon, and M. T. Ronan
Subjects: Physics, Particle physics, Crystallography, Antiparticle, Meson, Hadron, Production (computer science), Elementary particle, Lambda baryon, Energy (signal processing), Bar (unit)
Abstract: We report a measurement of the ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}p\overline{p}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ process with the TPC/Two-Gamma facility at the PEP ${e}^{+}{e}^{\ensuremath{-}}$ storage ring at SLAC. Forty-five $p\overline{p}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ events were identified in data corresponding to an integrated ${e}^{+}{e}^{\ensuremath{-}}$ luminosity of 142 ${\mathrm{pb}}^{\ensuremath{-}1}$. The cross section for $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}p\overline{p}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ is given both as a function of the $\ensuremath{\gamma}\ensuremath{\gamma}$ center-of-mass energy ${W}_{\ensuremath{\gamma}\ensuremath{\gamma}}$, with ${W}_{\ensuremath{\gamma}\ensuremath{\gamma}}$ between 2.5 and 5.5 GeV, and as a function of the in variant mass squared ${q}^{2}$ of one of the photons, with $\ensuremath{-}{q}^{2}l7$ Ge${\mathrm{V}}^{2}$. This cross section falls much less rapidly with ${W}_{\ensuremath{\gamma}\ensuremath{\gamma}}$ than does the cross section for a similar process, $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}p\overline{p}$. No ${\ensuremath{\Delta}}^{0}{\overline{\ensuremath{\Delta}}}^{0}$ production is observed, and only a small fraction of the events at low ${W}_{\ensuremath{\gamma}\ensuremath{\gamma}}$ is consistent with $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{\ensuremath{\Delta}}^{++}{\overline{\ensuremath{\Delta}}}^{\ensuremath{-}\ensuremath{-}}$, ${\ensuremath{\Delta}}^{++}\overline{p}{\ensuremath{\pi}}^{\ensuremath{-}}$, or ${\overline{\ensuremath{\Delta}}}^{\ensuremath{-}\ensuremath{-}}p{\ensuremath{\pi}}^{+}$. In an expanded search through the same data, four events compatible with either $\ensuremath{\Lambda}\overline{\ensuremath{\Lambda}}(\ensuremath{\Lambda}\ensuremath{\rightarrow}p{\ensuremath{\pi}}^{\ensuremath{-}})$ or ${\ensuremath{\Sigma}}^{0}\overline{\ensuremath{\Lambda}}({\ensuremath{\Sigma}}^{0}\ensuremath{\rightarrow}\ensuremath{\Lambda}\ensuremath{\gamma})$ production were found.
Published: 1989
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18. ΛProduction ine+e−Annihilation at 29 GeV

Author: B. A. Barnett, B. Gabioud, W. E. Slater, G. J. VanDalen, A. Pevsner, Hirotsugu Fujii, D. A. Park, Philippe Eberhard, A. Barbaro-Galtieri, J. W. Gary, W. Gorn, G. R. Lynch, C. S. Lindsey, K. Maruyama, R. F. van Daalen Wetters, Marjorie Shapiro, C. Y. Chien, K. A. Derby, W. Moses, M. Pripstein, L. T. Kerth, Werner Hofmann, H. K. Ticho, J. A. Bakken, P. J. Oddone, H. S. Kaye, J. E. Huth, R. R. Ross, M. T. Ronan, K. K. Kwong, R. J. Madaras, A. R. Clark, D. L. Fancher, H. Aihara, M. Yamauchi, A. Cordier, L. Madansky, J. M. Hauptman, C. D. Buchanan, J. Hylen, T. Kamae, H. Yamamoto, R. I. Koda, D. R. Nygren, Peter Nemethy, Barry Blumenfeld, A. D. Bross, J. A. J. Matthews, S. C. Loken, Owen Chamberlain, W.A. Wenzel, Gilbert Shapiro, Nicholas John Hadley, F. R. Rouse, M. L. Stevenson, X. Q. Lu, Mitchell Wayne, Toshitsugu Fujii, E. M. Wang, Margaret Alston-Garnjost, R. van Tyen, B. C. Shen, P. R. Robrish, S. O. Melnikoff, R. W. Kenney, N. Toge, W. M. Zhang, R. R. Kofler, J. N. Marx, Orin I. Dahl, C. T. Day, A. V. Barnes, D. H. Stork, R. R. Sauerwein, and J. G. Layter
Subjects: Physics, Particle physics, Annihilation, Electron–positron annihilation, Hadron, General Physics and Astronomy, Lambda baryon, Lambda, Baryon, Pair production, Antimatter, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Nuclear Experiment
Abstract: The inclusive production cross section of ..lambda.., anti ..lambda.. in e/sup +/e/sup -/ annihilation at a c.m. energy of 29 GeV has been measured with the time-projection-chamber detector at PEP. The average lambda, anti lambda multiplicity has been measured to be 0.197 +/- 0.012 (stat.) +/- 0.017 (syst.). ..lambda..-anti..lambda.. pairs have been observed in jets for the first time, and the average number of ..lambda..-anti..lambda.. pairs per event has been measured to be 0.042 +/- 0.017 +/- 0.014. 8 references, 3 figures.
Published: 1985
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19. Tests of Models for Parton Fragmentation by Means of Three-Jet Events ine+e−Annihilation ats=29GeV

Author: B. A. Barnett, W. M. Zhang, G. R. Lynch, R. R. Kofler, Mitchell Wayne, C. Y. Chien, L. Madansky, R. I. Koda, Orin I. Dahl, D. R. Nygren, N. Toge, J. A. Bakken, H. S. Kaye, Werner Hofmann, W. Moses, E. M. Wang, A. R. Clark, Margaret Alston-Garnjost, R. van Tyen, A. Cordier, Barry Blumenfeld, A. Pevsner, H. U. Bengtsson, J. G. Layter, B. Gabioud, Owen Chamberlain, J. N. Marx, Marjorie Shapiro, B. C. Shen, J. M. Hauptman, Peter Nemethy, J. E. Huth, Toshitsugu Fujii, Nicholas John Hadley, H. Yamamoto, D. L. Fancher, A. Barbaro-Galtieri, Y. Yamauchi, T. Kamae, C. T. Day, J. A. J. Matthews, K. Maruyama, Philippe Eberhard, J. W. Gary, F. R. Rouse, A. V. Barnes, S. O. Melnikoff, H. K. Ticho, R. F. van Daalen Wetters, D. H. Stork, A. D. Bross, P. R. Robrish, W.A. Wenzel, Gilbert Shapiro, R. R. Sauerwein, C. S. Lindsey, J. Hylen, W. E. Slater, L. T. Kerth, M. Pripstein, R. W. Kenney, X. Q. Lu, M. L. Stevenson, M. T. Ronan, K. A. Derby, K. K. Kwong, H. Aihara, G. J. VanDalen, Hirotsugu Fujii, D. A. Park, S. C. Loken, C. D. Buchanan, P. J. Oddone, R. R. Ross, R. J. Madaras, and W. Gorn
Subjects: Quantum chromodynamics, Physics, Particle physics, Annihilation, Mathematical model, Quark model, Hadron, Lund string model, General Physics and Astronomy, Parton, Elementary particle, Nuclear physics, High Energy Physics::Experiment, Nuclear Experiment
Abstract: The distribution of particles in three-jet events is compared with the predictions of three fragmentation models currently in use: the Lund string model, the Webber cluster model, and an independent fragmentation model. The Lund model and, to a certain extent, the Webber model provide reasonable descriptions of the data. The independent fragmentation model does not describe the distribution of particles at large angles with respect to the jet axes. The results provide evidence that the sources of hadrons are Lorentz boosted with respect to the overall c.m.
Published: 1985
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20. Performance of the hexagonal calorimeter at PEP-4

Author: S. C. Loken, P. J. Oddone, P. S. Martin, R. R. Ross, R. J. Madaras, J. A. Bakken, N. J. Hadley, C.Y. Chien, C. D. Buchanan, G. W. London, J. Hylen, M. E. Zeller, C. T. Day, J. N. Marx, O. Chamberlain, M. D. Shapiro, J. M. Hauptman, R. F. van Daalen Wetters, G. R. Lynch, Hiroaki Aihara, Mitchell Wayne, P. R. Robrish, X. Q. Lu, W. Gorn, A. Pevsner, H. J. Hilke, L. T. Kerth, H. Iwasaki, Barry Blumenfeld, B. Gabioud, J. Chiba, K. Maruyama, W. A. Wenzel, F. R. Rouse, H. Fujii, Werner Hofmann, D. R. Nygren, H. K. Ticho, J. A. J. Matthews, J. W. Gary, M. Pripstein, J. Mallet, D. L. Fancher, P. H. Eberhard, R. van Tyen, G. Shapiro, W. Moses, B. C. Shen, B. Heck, G. J. Van Dalen, M. Yamauchi, O. I. Dahl, William Carithers, M. Alston-Garnjost, L. Madansky, A. R. Clark, B. A. Barnett, R. I. Koda, H. Videau, S. O. Melnikoff, D. H. Badtke, A. D. Bross, R. M. Majka, W. M. Zhang, R. W. Kenney, R. R. Kofler, J. G. Layter, M. Urban, A. V. Barnes, D. H. Stork, W. E. Slater, P. Delpierre, C. S. Lindsey, A. Barbaro-Galtieri, J. E. Huth, K. A. Derby, P. Nemethy, M. L. Stevenson, T. Kamae, D. A. Park, N. Toge, M. T. Ronan, and K. K. Kwong
Subjects: Physics, Jet (fluid), Calorimeter (particle physics), Physics::Instrumentation and Detectors, business.industry, Monte Carlo method, General Engineering, Solid angle, STRIPS, law.invention, Optics, law, Calibration, High Energy Physics::Experiment, business, Image resolution, Projective geometry
Abstract: A Geiger-mode electromagnetic shower calorimeter has been constructed for PEP-4. Six trapezoidal modules cover 75% of 4 π solid angle in a hexagonal array. Each module contains 40 sense wire planes between 0.25 radiation-length thick lead-laminates, and is divided electrically into submodules of 27 and 13 layers. Half-degree wide hodoscopic channels in projective geometry provide excellent spatial resolution. In each gap three stereo views using the sense wires as well as strips on both cathodes at ±60° to the wires provide good shower reconstruction capabilities in multi-track jet events. Calibration and data analysis procedures are outlined. The performance of the calorimeter in the measurement of Bhabha events and the reconstruction of π 0 's in jet events is in excellent agreement with Monte Carlo simulations. The π 0 mass resolution is MeV (rms).
Published: 1983
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21. Spatial Resolution of the PEP-4 Time Projection Chamber

Author: B. C. Shen, K. A. Derby, D. H. Badtke, R. W. Kenney, A. Pevsner, H. Iwasaki, F. R. Rouse, Barry Blumenfeld, O. I. Dahl, J. E. Huth, A. Barbaro-Galtieri, M. Alston-Garnjost, K. Maruyama, L. Madansky, J. Chiba, J. Hylen, B. A. Barnett, R. I. Koda, Hiroaki Aihara, R. van Tyen, R. R. Kofler, J. M. Hauptman, H. K. Ticho, B. Gabioud, P. S. Martin, T. Fujii, R. J. Madaras, W. A. Wenzel, C. S. Lindsey, S. O. Melnikoff, M. E. Zeller, M. L. Stevenson, X-Q. Lu, M. D. Shapiro, J. G. Layter, A. D. Bross, J. N. Marx, Mitchell Wayne, H. Videau, D. R. Nygren, W. Moses, R. F. vanDaalen Wetters, J. W. Gary, P. Delpierre, P. J. Oddone, N. J. Hadley, N. Toge, J. A. Bakken, M. Yamauchi, G. Shapiro, Ronald Madaras, P. Nemethy, A. V. Barnes, R. R. Ross, H. Hilke, M. Pripstein, J. A. J. Matthews, G. J. Van Dalen, G. R. Lynch, Allan G Clark, D. H. Stork, P. R. Robrish, D. L. Fancher, J. Mallet, D. A. Park, O. Chamberlain, R. Majka, S. C. Loken, W. C. Carithers, P. H. Eberhard, C.Y. Chien, K. K. Kwong, H. Fujii, W-M. Zhang, M. T. Ronan, T. Kamae, W. E. Slater, C. D. Buchanan, M. Urban, W. Gorn, B. Heck, C. T. Day, and L. T. Kerth
Subjects: Physics, Nuclear and High Energy Physics, Argon, Time projection chamber, Physics::Instrumentation and Detectors, business.industry, Resolution (electron density), chemistry.chemical_element, Particle detector, Cathode, Magnetic field, law.invention, Optics, Nuclear magnetic resonance, Nuclear Energy and Engineering, chemistry, Physics::Plasma Physics, law, Measuring instrument, Electrical and Electronic Engineering, business, Image resolution
Abstract: The spatial resolution and response of the segmented cathode pads of the PEP-4 TPC have been measured with data taken at 8.5 atmospheres of 80% Argon-20% Methane gas with a 4kG magnetic field. The dependence of the spatial resolution and pad response on drift distance and track-anode crossing angle is presented.
Published: 1983
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22. Tests of models for quark and gluon fragmentation ine + e − annihilation at $$\sqrt s = 29 GeV$$

Author: R. I. Koda, J. A. J. Matthews, H. Yamamoto, R. R. Kofler, K. A. Derby, P. Nemethy, T. Kamae, H. K. Ticho, D. H. Stork, R. J. Madaras, W. Moses, H. Fujii, J. E. Huth, M. Yamauchi, F. R. Rouse, W. M. Zhang, H. S. Kaye, A. V. Barnes, Ronald R. Ross, R. F. van Daalen Wetters, C. Y. Chien, R. R. Sauerwein, P. R. Robrish, A. Cordier, Marjorie Shapiro, B. Gabioud, C. D. Buchanan, M. Pripstein, A. Pevsner, N. J. Hadley, C. S. Lindsey, L. Madansky, A. D. Bross, S. O. Melnikoff, L. T. Kerth, Orin I. Dahl, M. T. Ronan, Gilbert Shapiro, M. R. Wayne, C. T. Day, J. G. Layter, Robert W. Kenney, William A. Wenzel, B. C. Shen, G. Lynch, Angela Barbaro-Galtieri, G. J. van Dalen, B. J. Blumenfeld, P. J. Oddone, J. Hylen, Werner Hofmann, D. A. Park, W. Gorn, J. W. Gary, S. C. Loken, Margaret Alston-Garnjost, R. van Tyen, W. E. Slater, X. Q. Lu, B. A. Barnett, Philippe Eberhard, K. Maruyama, J. A. Bakken, A. R. Clark, H. U. Bengtsson, K. K. Kwong, D. R. Nygren, Owen Chamberlain, J. N. Marx, J. M. Hauptman, E. M. Wang, M. L. Stevenson, D. L. Fancher, N. Toge, and Hiroaki Aihara
Subjects: Quark, Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Lund string model, Elementary particle, Parton, Gluon, Nuclear physics, Pion, Quark–gluon plasma, High Energy Physics::Experiment, Nuclear Experiment, Engineering (miscellaneous)
Abstract: Three currently used fragmentation models are tested by studying the distribution of particles between jet axes in the 3-jet events ofe+e− annihilation, using data collected by the Time Projection Chamber at PEP. These three models — the Lund String model, the Webber Cluster model and an Independent Fragmentation model (IF) — each implement different Lorentz-frame structures for the fragmentation process of quarks and gluons into hadrons. The Lund model provides a good description of the data, while the IF model does not. The Webber model, which is untuned, does not describe the absolute particle densities between jets, but correctly predicts the ratios of those densities, which are less sensitive to the tuning.
Published: 1985
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23. Characteristics of Proton Production in Jets frome+e−Annihilation at 29 GeV

Author: X. Q. Lu, W. E. Slater, W.A. Wenzel, Gilbert Shapiro, W. Gorn, M. L. Stevenson, S. C. Loken, A. R. Clark, D. H. Badtke, J. G. Layter, Peter Nemethy, B. Gabioud, C. D. Buchanan, L. Madansky, A. Barbaro-Galtieri, G. R. Lynch, C. S. Lindsey, H. Iwasaki, Owen Chamberlain, H. J. Hilke, W. M. Zhang, R. I. Koda, H. Videau, P. S. Martin, R. R. Kofler, J. Chiba, J. A. Bakken, R. M. Majka, Philippe Eberhard, A. Cordier, S. O. Melnikoff, M. T. Ronan, K. K. Kwong, C. Y. Chien, C. T. Day, Marjorie Shapiro, Mitchell Wayne, Orin I. Dahl, D. R. Nygren, G. J. VanDalen, N. Toge, K. Maruyama, Werner Hofmann, P. J. Oddone, W. Moses, R. F. van Daalen Wetters, R. W. Kenney, Hirotsugu Fujii, D. A. Park, P. R. Robrish, J. A. J. Matthews, L. T. Kerth, J. M. Hauptman, R. R. Ross, R. J. Madaras, H. K. Ticho, H. Yamamoto, D. L. Fancher, Hiroaki Aihara, J. Hylen, K. A. Derby, J. W. Gary, B. A. Barnett, F. R. Rouse, M. Yamauchi, M. Pripstein, Toshitsugu Fujii, A. D. Bross, Margaret Alston-Garnjost, Nicholas John Hadley, R. van Tyen, J. E. Huth, B. C. Shen, J. N. Marx, Barry Blumenfeld, T. Kamae, A. V. Barnes, D. H. Stork, R. R. Sauerwein, and A. Pevsner
Subjects: Physics, Particle physics, Annihilation, Proton, Meson, Nuclear Theory, Hadron, General Physics and Astronomy, Elementary particle, Nuclear physics, Baryon, Pion, High Energy Physics::Experiment, Nuclear Experiment, Nucleon
Abstract: Proton production in e/sup +/e/sup -/ annihilation at 29 GeV has been studied with the time projection chamber. Measurements of the dependence of proton fractions on momentum, transverse momentum with respect to the jet axis, hadron multiplicity, and event sphericity are reported. Our results are consistent with the assumption that primary baryons and mesons have similar production spectra, and indicate that protons provide more direct probes of underlying fragmentation phenomena than do pions.
Published: 1984
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24. Baryon Production ine+e−Annihilation ats=29GeV: Clusters or Diquarks?

Author: W. Moses, D. L. Fancher, S. C. Loken, M. Yamauchi, B. C. Shen, A. D. Bross, X. Q. Lu, G. R. Lynch, H. U. Bengtsson, C. Y. Chien, Werner Hofmann, J. W. Gary, Marjorie Shapiro, Owen Chamberlain, J. N. Marx, B. A. Barnett, A. Cordier, Mitchell Wayne, J. M. Hauptman, H. Yamamoto, Barry Blumenfeld, M. Pripstein, A. V. Barnes, K. Maruyama, D. H. Stork, R. R. Sauerwein, P. R. Robrish, E. M. Wang, W.A. Wenzel, H. K. Ticho, W. M. Zhang, Philippe Eberhard, F. R. Rouse, R. R. Kofler, Gilbert Shapiro, Margaret Alston-Garnjost, R. van Tyen, W. Gorn, Orin I. Dahl, D. R. Nygren, S. O. Melnikoff, J. A. J. Matthews, M. L. Stevenson, J. G. Layter, Toshitsugu Fujii, R. W. Kenney, C. T. Day, C. S. Lindsey, G. J. VanDalen, P. J. Oddone, Hirotsugu Fujii, R. R. Ross, J. Hylen, L. Madansky, D. A. Park, R. J. Madaras, Peter Nemethy, C. D. Buchanan, R. I. Koda, Nicholas John Hadley, K. A. Derby, J. A. Bakken, H. S. Kaye, M. T. Ronan, N. Toge, K. K. Kwong, H. Aihara, W. E. Slater, R. F. van Daalen Wetters, L. T. Kerth, B. Gabioud, A. Barbaro-Galtieri, A. R. Clark, J. E. Huth, T. Kamae, and A. Pevsner
Subjects: Physics, Particle physics, Annihilation, Meson, High Energy Physics::Lattice, High Energy Physics::Phenomenology, Nuclear Theory, Hadron, Quark model, General Physics and Astronomy, Elementary particle, Nuclear physics, Baryon, Diquark, Pair production, High Energy Physics::Experiment, Nuclear Experiment
Abstract: We use the time-projection chamber detector to study mechanisms of baryon production in the central rapidity region of jets from e/sup +/e/sup -/ annihilation. On the basis of angular correlations between protons and antiprotons, we exclude the isotropic decay of heavy mesonic clusters as a dominant source of baryons at 95% confidence level. The diquark mechanisms used in string fragmentation models reproduce the data, provided that diquarks are formed in a two-step process which allows mesons to be produced in between the baryon and antibaryon.
Published: 1985
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25. Measurement ofτbranching ratios

Author: H. Aihara, M. Alston-Garnjost, R. E. Avery, J. A. Bakken, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, D. A. Bauer, H.-U. Bengtsson, D. L. Bintinger, G. J. Bobbink, T. S. Bolognese, A. D. Bross, C. D. Buchanan, A. Buijs, D. O. Caldwell, C-Y. Chien, A. R. Clark, G. D. Cowan, D. A. Crane, O. I. Dahl, K. A. Derby, J. J. Eastman, T. K. Edberg, P. H. Eberhard, A. M. Eisner, R. Enomoto, F. C. Erné, T. Fujii, J. W. Gary, W. Gorn, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X-Q. Lu, G. R. Lynch, L. Madansky, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, G. E. Masek, L. G. Mathis, J. A. J. Matthews, S. J. Maxfield, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Park, S. K. Park, D. E. Pellett, A. Pevsner, M. Pripstein, M. T. Ronan, R. R. Ross, F. R. Rouse, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, J. S. Steinman, M. L. Stevenson, D. H. Stork, M. G. Strauss, M. K. Sullivan, T. Takahashi, J. R. Thompson, N. Toge, S. Toutounchi, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, Z. R. Wolf, H. Yamamoto, S. J. Yellin, C. Zeitlin, and W-M. Zhang
Subjects: Nuclear physics, Physics, Semileptonic decay, Particle decay, Particle physics, Muon, Pion, Meson, Branching fraction, Hadron, Lepton
Abstract: Using the data accumulated at LEP in 1989 and 1990 with the ALEPH detector, the inclusive and exclusive branching ratios of the τ lepton have been measured assuming lepton universality inZ0 decays. The inclusive branching fractions for the τ decay into one, three, and five charged particles have been determined to be (85.45±0.97)%, (14.35±0.48)%, and (0.10±0.05)%, respectively, in agreement with the world averages. New undetected decay modes are determined to have a branching fraction of less than 2.1% at 95% CL. The measured branching ratios for quasi-exclusive channels are slightly larger than, but consistent with the world averages, except for the modes τ→3 hadrons+v τ andτ→hadron+2π0v τ , which are significantly larger. These latter branching ratios have been found to be (9.5±0.7)% and (10.2±1.1)%, respectively. The sum of all the measured quasi-exclusive branching ratios is (100.4±1.8)%. A fully exclusive analysis of modes with neutral pions shows no evidence for new photonic decay modes with a branching fraction limit of 3.4% at 95% CL.
Published: 1987
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26. Observation of scaling of the photon structure functionF2γat lowQ2

Author: T. Fujii, C. Zeitlin, B. A. Barnett, W. Vernon, Xiaochuan Lu, H. Yamamoto, S. O. Melnikoff, D. A. Bauer, J. W. Gary, G. E. Masek, J. R. Smith, D. R. Nygren, A. Lu, F. L. Linde, G. Shapiro, M. Pripstein, K. Maeshima, L. T. Kerth, K. K. Kwong, M. T. Ronan, W. E. Slater, J. J. Eastman, M. G. Strauss, R. R. Kofler, G. R. Lynch, S. J. Maxfield, P. H. Eberhard, W. M. Zhang, M. K. Sullivan, R. I. Koda, D. A. Park, W. G.J. Langeveld, M. R. Wayne, J. T. White, R. R. McNeil, Sung-Ho Park, F. R. Rouse, B. C. Shen, D. E. Pellett, W. Moses, S. C. Loken, R. W. Kenney, C. D. Buchanan, T. S. Bolognese, W.A. Wenzel, P. H.U. Bengtsson, D. H. Stork, D. O. Caldwell, J. A.J. Matthews, S. Toutounchi, K. A. Schwitkis, D. L. Bintinger, M. C.S. Williams, M. Alston-Garnjost, Z. R. Wolf, M. L. Stevenson, H. S. Kaye, L. G. Mathis, Werner Hofmann, P. Némethy, K. A. Derby, J. R. Thompson, G. J. Bobbink, T. K. Edberg, A. M. Eisner, J. E. Huth, A. R. Clark, W. Gorn, Marjorie Shapiro, A. D. Bross, Hiroaki Aihara, Winston Ko, C. S. Lindsey, J. C. Sens, G. D. Cowan, E. M. Wang, A. Barbaro-Galtieri, T. Takahashi, R. van Tyen, T. Kamae, R. E. Avery, A. Buijs, J. Hylen, J. S. Steinman, P. J. Oddone, D. A. Crane, R. R. Ross, K. H. Kees, R. J. Madaras, A. V. Barnes, Yayu Wang, F. C. Erné, H. P. Paar, E. S. Miller, B. Van Uitert, J. N. Marx, J. G. Layter, R. L. Lander, B. D. Magnuson, S. J. Yellin, W. Wagner, A. R. Barker, G. J. VanDalen, R. Enomoto, J. M. Hauptman, O. I. Dahl, N. Toge, and R. F. Van Daalen Wetters
Subjects: Physics, General Physics and Astronomy, Atomic physics, Scaling, Photon structure function
Published: 1987
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27. Inclusive γ and π0 production cross sections and energy fractions ine + e − annihilation at 29 GeV

Author: J. A. Bakken, J. Hylen, Hirotsugu Fujii, D. A. Park, B. A. Barnett, R. R. Kofler, L. Madansky, R. I. Koda, R. J. Madaras, William A. Wenzel, J. W. Gary, Owen Chamberlain, S. C. Loken, M. Yamauchi, P. J. Oddone, Gilbert Shapiro, M. R. Wayne, A. R. Clark, H. Iwasaki, D. R. Nygren, J. N. Marx, H. S. Kaye, J. G. Layter, H. Yamamoto, K. A. Derby, A. Pevsner, X. Q. Lu, G. Lynch, K. K. Kwong, C. S. Lindsey, Philippe Eberhard, W. Gorn, Marjorie Shapiro, J. E. Huth, M. L. Stevenson, W. M. Zhang, H. Aihara, Margaret Alston-Garnjost, R. van Tyen, A. Cordier, J. M. Hauptman, B. C. Shen, B. Gabioud, P. Nemethy, D. L. Fancher, Orin I. Dahl, Barry Blumenfeld, C. D. Buchanan, A. D. Bross, Toshitsugu Fujii, Angela Barbaro-Galtieri, E. M. Wang, W. E. Slater, M. T. Ronan, M. Pripstein, N. Toge, D. H. Stork, L. T. Kerth, R. R. Sauerwein, K. Maruyama, Hans-Uno Bengtsson, A. V. Barnes, J. A. J. Matthews, R. F. van Daalen Wetters, W. Moses, H. K. Ticho, P. R. Robrish, G. J. Van Dalen, T. Kamae, C. Y. Chien, Werner Hofmann, Ronald R. Ross, J. Chiba, S. O. Melnikoff, F. R. Rouse, C. T. Day, Robert W. Kenney, H. Videau, and N. J. Hadley
Subjects: Physics, Particle physics, Antiparticle, Annihilation, Physics and Astronomy (miscellaneous), Meson, Branching fraction, Nuclear physics, Massless particle, Pion, Antimatter, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Engineering (miscellaneous), Lepton
Abstract: Inclusive production cross sections for photons and π0's ine + e − annihilation at a center of mass energy of 29 GeV have been measured. The π0 production spectrum agrees with a corresponding measurement for π±. The ratio of the π0 inclusive rate to the average for π± is 0.92±0.14. The fractions of the total energy carried by photons and π0's are 0.244±0.016 and 0.217±0.033, respectively. The fraction of total energy carried by all stable hadrons, prompt leptons and photons is determined to be 0.938±0.045, leaving 0.062±0.045 for neutrinos.
Published: 1985
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28. Evidence for a Spin-1 Particle Produced by Two Photons

Author: H. Aihara, M. Alston-Garnjost, R. E. Avery, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, D. A. Bauer, H. -U. Bengtsson, D. L. Bintinger, G. J. Bobbink, T. S. Bolognese, A. D. Bross, C. D. Buchanan, A. Buijs, D. O. Caldwell, A. R. Clark, G. D. Cowan, D. A. Crane, O. I. Dahl, K. A. Derby, J. J. Eastman, P. H. Eberhard, T. K. Edberg, A. M. Eisner, R. Enomoto, F. C. Erné, T. Fujii, J. W. Gary, W. Gorn, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X. -Q. Lu, G. R. Lynch, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, G. E. Masek, L. G. Mathis, J. A. J. Matthews, S. J. Maxfield, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Park, S. K. Park, D. E. Pellett, M. Pripstein, M. T. Ronan, R. R. Ross, F. R. Rouse, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, J. S. Steinman, M. L. Stevenson, D. H. Stork, M. G. Strauss, M. K. Sullivan, T. Takahashi, J. R. Thompson, N. Toge, S. Toutounchi, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, Z. R. Wolf, H. Yamamoto, S. J. Yellin, C. Zeitlin, W. -M. Zhang, and IHEF (IoP, FNWI)
Subjects: Physics, Particle physics, Photon, Meson, General Physics and Astronomy, Resonance, Particle, High Energy Physics::Experiment, Production (computer science), Storage ring, Spin-½
Abstract: Two-photon production of ${K}_{S}^{0}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ensuremath{\mp}}$ states has been studied by the TPC/Two-Gamma experiment at the SLAC storage ring PEP. A resonance of mass 1.42 GeV was seen when one of the photons was quite virtual but not when both photons were nearly real. Production of a spin-1 meson, which cannot be made by two real photons, would fit these observations. The ${Q}^{2}$ dependence of the data in the resonance region agrees with this spin assignment and is incompatible with a spin-0 hypothesis. The mass and width of the resonance are similar to those of the $E$ meson, which has been assigned ${J}^{P}={0}^{\ensuremath{-}}$ and ${J}^{P}={1}^{+}$ by different experiments.
Published: 1986
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29. Experimental limit on the decayτ−→ντK−K0

Author: H. Aihara, M. Alston-Garnjost, R. E. Avery, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, D. A. Bauer, H. -U. Bengtsson, D. L. Bintinger, G. J. Bobbink, T. S. Bolognese, A. D. Bross, C. D. Buchanan, A. Buijs, D. O. Caldwell, A. R. Clark, G. D. Cowan, D. A. Crane, O. I. Dahl, K. A. Derby, J. J. Eastman, P. H. Eberhard, T. K. Edberg, A. M. Eisner, R. Enomoto, F. C. Erné, T. Fujii, J. W. Gary, W. Gorn, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X. -Q. Lu, G. R. Lynch, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, G. E. Masek, L. G. Mathis, J. A. J. Matthews, S. J. Maxfield, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Park, S. K. Park, D. E. Pellett, M. Pripstein, M. T. Ronan, R. R. Ross, F. R. Rouse, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, J. S. Steinman, M. L. Stevenson, D. H. Stork, M. G. Strauss, M. K. Sullivan, T. Takahashi, J. R. Thompson, N. Toge, S. Toutounchi, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, Z. R. Wolf, H. Yamamoto, S. J. Yellin, C. Zeitlin, and W. -M. Zhang
Subjects: Physics, Particle physics, Tau neutrino, Electron–positron annihilation, General Physics and Astronomy, Limit (mathematics)
Published: 1987
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30. Charged-Hadron Inclusive Cross Sections and Fractions ine+e−Annihilation ats=29GeV

Author: A.R. Barker, D. R. Nygren, H. Yamamoto, J. G. Layter, G. E. Masek, J. M. Hauptman, S. J. Yellin, W. Moses, F. C. Erné, A. M. Eisner, F. R. Rouse, J. C. Sens, Z. R. Wolf, W. Vernon, M. Pripstein, S. Khacheryan, D. O. Caldwell, S. J. Maxfield, M. K. Sullivan, D. H. Stork, W. G.J. Langeveld, G. Cowan, J. R. Smith, Philippe Eberhard, R. R. Kofler, R. W. Kenney, B. C. Shen, A. Barbaro-Galtieri, Orin I. Dahl, D.A. Bauer, A. Lu, S. Toutounchi, Wolfgang Wagner, D. A. Crane, S. K. Park, J. Hylen, J. A. J. Matthews, T. K. Edberg, D. E. Pellett, F.L. Linde, B. D. Magnuson, A. R. Clark, G. J. Bobbink, H. P. Paar, J. S. Steinman, C. D. Buchanan, G. R. Lynch, H. Y. Chao, W.A. Wenzel, M. G. Strauss, T. Kamae, S. C. Loken, Gilbert Shapiro, Werner Hofmann, K. A. Derby, A. Bay, Y. X. Wang, Tadayuki Takahashi, M. L. Stevenson, P. J. Oddone, E. M. Wang, R. R. Ross, R. J. Madaras, Margaret Alston-Garnjost, R. van Tyen, H. S. Kaye, M. T. Ronan, K. H. Fairfield, H. Aihara, Ryoji Enomoto, E. S. Miller, K. A. Schwitkis, A. Buijs, R.E. Avery, J. J. Eastman, M. Daoudi, B. A. Barnett, L. Mathis, W. T. Lin, S. B. Chun, C. Zeitlin, and R. W. Stephens
Subjects: Nuclear physics, Physics, Particle physics, Annihilation, Hadron, General Physics and Astronomy
Published: 1988
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31. Measurement of Ionization Loss in the Relativistic Rise Region with the Time Projection Chamber

Author: L. Madansky, W. E. Slater, W. Gorn, C.Y. Chien, J. A. Bakken, B. Gabioud, M. T. Ronan, A. V. Barnes, J. M. Hauptman, J. A. J. Matthews, R. I. Koda, M. Urban, H. Hilke, C. D. Buchanan, K. K. Kwong, R. van Tyen, J. G. Layter, B. A. Barnett, W-M. Zhang, P. R. Robrish, S. C. Loken, W. C. Carithers, R. F. vanDaalen Wetters, J. Mallet, M. Yamauchi, P. S. Martin, Hiroaki Aihara, H. Fujii, P. H. Eberhard, K. A. Derby, K. Maruyama, T. Fujii, R. R. Kofler, T. Kamae, A. D. Bross, G. Shapiro, Ronald Madaras, M. L. Stevenson, M. D. Shapiro, Bernard Gabioud, G. R. Lynch, X-Q. Lu, B. Heck, J. E. Huth, J. Chiba, D. A. Park, O. Chamberlain, N. Toge, C. T. Day, M. Alston-Garnjost, H. K. Ticho, D. L. Fancher, R. R. Ross, J. W. Gary, F. R. Rouse, W. Moses, M. Pripstein, J. N. Marx, D. H. Stork, S. O. Melnikoff, P. J. Oddone, D. R. Nygren, J. Hylen, P. Nemethy, L. T. Kerth, R. Majka, H. Iwasaki, A. Pevsner, Barry Blumenfeld, H. Videau, N. J. Hadley, G. J. Van Dalen, A. Barbaro-Galtieri, O. I. Dahl, M. E. Zeller, A. R. Clark, Mitchell Wayne, D. H. Badtke, R. W. Kenney, W. A. Wenzel, C. S. Lindsey, P. Delpierre, and B. C. Shen
Subjects: Physics, Nuclear and High Energy Physics, Time projection chamber, Astrophysics::High Energy Astrophysical Phenomena, Resolution (electron density), Cosmic ray, Particle identification, Standard deviation, Cathode, law.invention, Nuclear physics, Nuclear Energy and Engineering, law, Ionization, Calibration, High Energy Physics::Experiment, Electrical and Electronic Engineering
Abstract: We present here some results obtained with the LBL Time Projection Chamber (TPC) regarding the particle identification by the measurement of the ionization losses in the relativistic rise region. This includes the method of calibration using 55Fe sources, the measurement of the resolution using cosmic rays, which shows an equivalent K-? separation of 4.8 standard deviations at 3.5 GeV/c, and the preliminary results obtained with multihadronic events from e+e- annihilations.
Published: 1983
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32. Experimental limit onι→γγand the interpretation of the iota as a glueball

Author: H. Aihara, M. Alston-Garnjost, R. E. Avery, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, D. A. Bauer, H.-U. Bengtsson, D. L. Bintinger, B. J. Blumenfeld, G. J. Bobbink, A. D. Bross, C. D. Buchanan, A. Buijs, M. P. Cain, D. O. Caldwell, O. Chamberlain, C.-Y. Chien, A. R. Clark, G. D. Cowan, D. A. Crane, O. I. Dahl, K. A. Derby, J. J. Eastman, P. H. Eberhard, A. M. Eisner, R. Enomoto, F. C. Erne, T. Fujii, B. Gabioud, J. W. Gary, W. Gorn, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, U. P. Joshi, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X-Q. Lu, G. R. Lynch, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, K. Maruyama, G. E. Masek, L. G. Mathis, J. A. J. Matthews, S. J. Maxfield, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Park, D. E. Pellett, M. Pripstein, M. T. Ronan, R. R. Ross, F. R. Rouse, R. R. Sauerwein, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, J. S. Steinman, M. L. Stevenson, D. H. Stork, M. G. Strauss, M. K. Sullivan, T. Takahashi, J. R. Thompson, N. Toge, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, Z. R. Wolf, H. Yamamoto, M. Yamauchi, S. J. Yellin, C. Zeitlin, and W.-M. Zhang
Subjects: Physics, Nuclear physics, Iota, Particle physics, Pion, Pair production, Meson, Glueball, Branching fraction, Hadron, General Physics and Astronomy, Spectral line
Abstract: By observing the reaction ..gamma gamma -->..K-italic/sub s-italic//sup 0/K/sup +-/..pi../sup minus-or-plus/, the TPC/Two-Gamma experiment at the SLAC e-italic/sup +/e/sup -/ storage ring PEP has obtained a 95%-confidence-level limit of GAMMA/sub iota//sub ..-->..//sub ..gamma..//sub ..gamma../B(iota..-->..KK-bar..pi..) ..//sub ..gamma..//sub ..gamma../ limit appears to conflict with previous assignments of an observed rho..gamma.. decay to iota and also with many analyses of eta-eta'-iota mixing. The contrast of this small ..gamma gamma.. width with the large rate for J-italic/psi..--> gamma..iota is evidence that the iota is a glueball with little admixture of q-italicq-bar states.
Published: 1986
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33. Charged Hadron Production ine+e−Annihilation at 29 GeV

Author: H. Aihara, M. Alston-Garnjost, D. H. Badke, J. A. Bakken, A. Barbaro-Galtieri, A. V. Barnes, B. A. Barnett, B. J. Blumenfeld, A. D. Bross, C. D. Buchanan, O. Chamberlain, C. Chen, J. Chiba, C. -Y. Chien, A. R. Clark, O. I. Dahl, C. T. Day, P. Delpierre, K. A. Derby, P. H. Eberhard, D. L. Fancher, H. Fujii, T. Fujii, B. Gabioud, J. W. Gary, W. Gorn, W. Gu, N. J. Hadley, J. M. Hauptman, H. J. Hilke, W. Hofmann, J. E. Huth, J. Hylen, H. Iwasaki, T. Kamae, R. W. Kenney, L. T. Kerth, R. I. Koda, R. R. Kofler, K. K. Kwong, J. G. Layter, C. S. Lindsey, S. C. Loken, G. W. London, X. -Q. Lu, G. R. Lynch, L. Madansky, R. J. Madaras, R. Majka, J. Mallet, P. S. Martin, K. Maruyama, J. N. Marx, J. A. Matthews, S. O. Melnikoff, W. Moses, P. Nemethy, D. R. Nygren, P. J. Oddone, D. A. Park, A. Pevsner, M. Pripstein, P. R. Robrish, M. T. Ronan, R. R. Ross, F. R. Rouse, R. R. Sauerwein, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, M. L. Stevenson, D. H. Stork, H. K. Ticho, N. Toge, M. Urban, R. F. van Daalen Wetters, G. J. VanDalen, R. van Tyen, H. Videau, M. R. Wayne, W. A. Wenzel, H. A. Yamamoto, M. Yamauchi, M. E. Zeller, and W. -M. Zhang
Subjects: Nuclear physics, Baryon, Physics, Particle physics, Annihilation, Time projection chamber, Meson, Electron–positron annihilation, General Physics and Astronomy, High Energy Physics::Experiment, Charged particle, Particle identification, Hadronization
Abstract: Data from the Time Projection Chamber at the SLAC storage ring PEP have been used to study the inclusive production of charged hadrons. Particles were identified by simultaneous dE/dx and momentum measurements. Cross sections and particle fractions for pi +/-, k+/-, and p(anti-p) are given as a function of several variables. Predictions of various hadronization models are compared to the data. A comparison is made with other fragmentation processes.
Published: 1984
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34. Prompt electron production ine + e − annihilations at 29 GeV

Author: J. N. Marx, T. Fujii, S. C. Loken, P. H. Eberhard, D. L. Fancher, J. A. J. Matthews, N. Toge, Allan G Clark, D. H. Stork, R. I. Koda, A. V. Barnes, W. Gorn, P. S. Martin, O. Chamberlain, H. K. Ticho, Gj Vandalen, B. A. Barnett, R. J. Madaras, M. T. Ronan, H. Iwasaki, Werner Hofmann, Hiroaki Aihara, J. A. Bakken, J. Chiba, P. R. Robrish, D. H. Badtke, W. E. Slater, R. W. Kenney, R. R. Ross, S. O. Melnikoff, L. Madansky, Marjorie Shapiro, F. R. Rouse, C. D. Buchanan, R. R. Kofler, T. Kamae, B. C. Shen, P. Nemethy, M. R. Wayne, J. W. Gary, D. A. Park, M. L. Stevenson, G. Shapiro, M. Yamauchi, A. Cordier, A. Barbaro-Galtieri, X. Q. Lu, C. S. Lindsey, H. Fujii, H. Yamamoto, R. R. Sauerwein, W. M. Zhang, B. Gabioud, H. Hilke, J. M. Hauptman, K. Maruyama, P. J. Oddone, M. Pripstein, W. Moses, H. Videau, W. A. Wenzel, J. G. Layter, Orin I. Dahl, C. Y. Chien, C. T. Day, R. van Tyen, A. Pevsner, N. J. Hadley, R. F. van Daalen Wetters, R. Majka, B. J. Blumenfeld, A. D. Bross, G. Lynch, K. A. Derby, J. E. Huth, M. Alston-Garnjost, L. T. Kerth, J. Hylen, M. E. Zeller, K. K. Kwong, and D. R. Nygren
Subjects: Nuclear physics, Quark, Physics, Particle decay, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Neutral current, Branching fraction, Electron–positron annihilation, Elementary particle, Engineering (miscellaneous), Lepton
Abstract: We have measured the inclusive prompt electron cross section over a wide momentum range (P>0.5 GeV/c) with the PEP-4 TPC detector. The semielectronic branching fractions of thec andb quarks are (9.1±0.9 (stat.)±1.3 (syst.))% and (11.0±1.8±1.0)%, respectively. Theb quark fragmentation function peaks at highz with 〈zb〉=0.74±0.05±0.03. The axial couplings to the neutral current areac=2.3±1.4±1.0 for thec quark andab=−2.0±1.9±0.5 for theb quark.
Published: 1985
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35. Quark fragmentation functions and long-range correlations ine + e ? annihilation at 29 GeV

Author: M. L. Stevenson, Ronald R. Ross, T. Fujii, R. R. Kofler, T. Kamae, K. K. Kwong, D. L. Fancher, C. S. Lindsey, D. A. Park, X. Q. Lu, M. Yamauchi, L. Madansky, R. R. Sauerwein, Owen Chamberlain, H. S. Kaye, J. A. Bakken, D. R. Nygren, J. N. Marx, N. Toge, P. Nemethy, Orin I. Dahl, Gilbert Shapiro, M. R. Wayne, Angela Barbaro-Galtieri, W. E. Slater, J. M. Hauptman, Margaret Alston-Garnjost, H. U. Bengtsson, Hiroaki Aihara, R. van Tyen, A. Cordier, Marjorie Shapiro, A. V. Barnes, B. Gabioud, W. Gorn, Philippe Eberhard, E. R. Rouse, P. R. Robrish, C. D. Buchanan, H. Fujii, B. A. Barnett, M. Pripstein, H. K. Ticho, K. Maruyama, J. Hylen, E. M. Wang, G. Lynch, L. T. Kerth, M. T. Ronan, C. Y. Chien, R. I. Koda, A. R. Clark, C. T. Day, H. Yamamoto, G. J. van Dalen, J. G. Layter, B. C. Shen, W. Moses, Robert W. Kenney, W. M. Zhang, R. J. Madaras, S. C. Loken, S. O. Melnikoff, R. F. van Daalen Wetters, B. J. Blumenfeld, J. W. Gary, K. A. Derby, A. Pevsner, N. J. Hadley, J. E. Huth, J. A. J. Matthews, D. H. Stork, William A. Wenzel, P. J. Oddone, Werner Hofmann, and A. D. Bross
Subjects: Quark, Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Particle model, High Energy Physics::Lattice, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, Elementary particle, Nuclear physics, Fragmentation (mass spectrometry), Transverse momentum, High Energy Physics::Experiment, Nuclear Experiment, Engineering (miscellaneous), Interaction range
Abstract: We study long-range correlations between hadrons in opposite jets ine+e− annihilation events at$\sqrt s $=29 GeV. We use the data to measure differences between quark and antiquark fragmentation functions into charged hadrons, and to estimate the variation of fragmentation properties among quark flavors. We find large variations in longitudinal fragmentation functions, but universal mean transverse momenta of hadrons in jets.
Published: 1985
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36. Performance of the Signal Processing System for the Time Projection Chamber

Author: K. Maruyama, J. N. Marx, Stewart C. Loken, H. K. Ticho, M. E. Zeller, L. Madansky, W. Moses, A. D. Bross, M. D. Shapiro, R. I. Koda, M. Yamauchi, R. R. Ross, Mitchell Wayne, Allan G Clark, R. van Tyen, M. Pripstein, N. Toge, P. J. Oddone, H. Fujii, G. R. Lynch, J. A. Bakken, D. H. Stork, B. Heck, C. T. Day, F. R. Rouse, D. L. Fancher, B. A. Barnett, G. Shapiro, K. A. Derby, Hiroaki Aihara, W. Gorn, R. R. Kofler, H. Hilke, A. V. Barnes, L. T. Kerth, M. L. Stevenson, B. C. Shen, T. Fujii, M. T. Ronan, S. C. Loken, W. C. Carithers, X-Q. Lu, K. K. Kwong, P. S. Martin, J. A. J. Matthews, A. Pevsner, H. Videau, C. D. Buchanan, P. H. Eberhard, P. R. Robrish, J. W. Gary, Barry Blumenfeld, N. J. Hadley, D. A. Park, O. Chamberlain, J. Hylen, J. E. Huth, W. E. Slater, R. J. Madaras, G. J. Van Dalen, J. G. Layter, M. Urban, M. Alston-Garnjost, P. Nemethy, B. Gabioud, R. Majka, A. Barbaro-Galtieri, R. F. vanDaalen Wetters, C.Y. Chien, O. I. Dahl, D. R. Nygren, J. Mallet, J. M. Hauptman, H. Iwasaki, D. H. Badtke, R. W. Kenney, S. O. Melnikoff, J. Chiba, W-M. Zhang, T. Kamae, W. A. Wenzel, C. S. Lindsey, and P. Delpierre
Subjects: Nuclear and High Energy Physics, Engineering, Signal processing, Time projection chamber, business.industry, Detector, Electrical engineering, System testing, Optics, Nuclear Energy and Engineering, Ionization, Electronics, Electrical and Electronic Engineering, business, Image resolution
Abstract: The Time Projection Chamber has operated in the PEP colliding beams at SLAC since January 1982. Its signal processing system, containing 16020 channels, has been calibrated and monitored using a computer-controlled test pulser system. We describe the test system and review measurements made with the system of signal processing electronics.
Published: 1983
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37. Comparison of the Particle Flow inqq¯gandqq¯γEvents ine+e−Annihilation

Author: S. O. Melnikoff, A.R. Barker, R. R. van Daalen Wetters, M. Yamauchi, A. D. Bross, F.L. Linde, A. Buijs, S. J. Yellin, E. M. Wang, R. W. Kenney, R.E. Avery, W. E. Slater, Margaret Alston-Garnjost, R. van Tyen, T. Bolognese, J. S. Steinman, J. N. Marx, M. T. Ronan, K. K. Kwong, J. E. Huth, C. S. Lindsey, J. M. Hauptman, H. Aihara, D. A. Crane, Y. X. Wang, Tadayuki Takahashi, B. C. Shen, H. P. Paar, D. L. Bintinger, K. Maruyama, G. E. Masek, J. A. J. Matthews, P. J. Oddone, C. Zeitlin, T. Kamae, D.A. Bauer, D. E. Pellet, M. G. Strauss, R. R. Ross, W.A. Wenzel, R. I. Koda, Gilbert Shapiro, Philippe Eberhard, R. J. Madaras, M. S. C. Williams, B. D. Magnuson, M. L. Stevenson, H. U. Bengtsson, W. Vernon, S. J. Maxfield, J. J. Eastman, C. D. Buchanan, M. Pripstein, G. Cowan, W. G.J. Langeveld, G. J. VanDalen, X. Q. Lu, W. Moses, L. T. Kerth, D. A. Park, B. van Uitert, H. S. Kaye, Z. R. Wolf, S. C. Loken, A. Lu, M. K. Sullivan, J. Hylen, Ryoji Enomoto, G. R. Lynch, M. P. Cain, Peter Nemethy, W. Gorn, J. W. Gary, F. C. Erné, B. A. Barnett, A. M. Eisner, Werner Hofmann, Kaori Maeshima, G. J. Bobbink, A. R. Clark, Winston Ko, J. R. Smith, K. A. Derby, A. V. Barnes, D. H. Stork, K. H. Kees, J. G. Layter, W. M. Zhang, R. R. Kofler, Orin I. Dahl, Wolfgang Wagner, D. R. Nygren, Marjorie Shapiro, H. Yamamoto, F. R. Rouse, N. Toge, L. Mathis, R. R. McNeil, R. Lander, Toshitsugu Fujii, Mitchell Wayne, J. Thompson, E. S. Miller, K. A. Schwitkis, A. Barbaro-Galtieri, J. C. Sens, D. O. Caldwell, and J. T. White
Subjects: Quark, Quantum chromodynamics, Physics, Particle physics, Annihilation, Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Lattice, Electron–positron annihilation, Nuclear Theory, High Energy Physics::Phenomenology, General Physics and Astronomy, Elementary particle, Jet (particle physics), Nuclear physics, Massless particle, High Energy Physics::Experiment, Event (particle physics)
Abstract: We compare the particle flow in the event plane of three-jet qq-barg (quark-antiquark-gluon) events with the particle flow in radiative annihilation events qq-bar..gamma.. (quark-antiquark-photon) for similar kinematic configurations. In the angular region between quark and antiquark jet, we find a significant decrease in particle density for qq-barg as compared to qq-bar..gamma... This effect is predicted in QCD as a result of destructive interference between soft-gluon radiation from quark, antiquark, and hard gluon.
Published: 1986
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38. φ- Meson Production ine+e−Annihilations at 29 GeV

Author: W. M. Zhang, W. Moses, R. R. Kofler, J. Chiba, M. T. Ronan, K. K. Kwong, K. A. Derby, B. A. Barnett, Toshitsugu Fujii, J. N. Marx, Orin I. Dahl, H. Aihara, X. Q. Lu, D. L. Fancher, A. Pevsner, M. E. Zeller, A. Cordier, L. Madansky, R. I. Koda, H. Videau, P. R. Robrish, Mitchell Wayne, J. G. Layter, W.A. Wenzel, Gilbert Shapiro, Barry Blumenfeld, M. L. Stevenson, W. Gorn, J. W. Gary, G. J. VanDalen, Margaret Alston-Garnjost, R. van Tyen, Hirotsugu Fujii, Nicholas John Hadley, D. A. Park, Marjorie Shapiro, M. Yamauchi, B. C. Shen, Peter Nemethy, C. T. Day, C. D. Buchanan, A. D. Bross, A. V. Barnes, J. E. Huth, S. C. Loken, J. A. J. Matthews, K. Maruyama, C. S. Lindsey, G. R. Lynch, D. H. Stork, R. R. Sauerwein, R. M. Majka, H. J. Hilke, H. Yamamoto, T. Kamae, C. Y. Chien, D. R. Nygren, H. K. Ticho, J. M. Hauptman, Owen Chamberlain, Werner Hofmann, P. S. Martin, W. E. Slater, F. R. Rouse, P. J. Oddone, Philippe Eberhard, A. Barbaro-Galtieri, R. R. Ross, R. J. Madaras, N. Toge, J. Hylen, M. Pripstein, S. O. Melnikoff, R. W. Kenney, B. Gabioud, H. Iwasaki, A. R. Clark, D. H. Badtke, R. F. van Daalen Wetters, L. T. Kerth, and J. A. Bakken
Subjects: Physics, Particle physics, Annihilation, Meson, Physics::Instrumentation and Detectors, Electron–positron annihilation, Hadron, General Physics and Astronomy, Elementary particle, Phi meson, Nuclear physics, Particle decay, High Energy Physics::Experiment, Boson
Abstract: Production of phi mesons in e/sup +/e/sup -/ annihilation at a center-of-mass energy of 29 GeV has been observed with the time-projection chamber detector at the PEP storage ring. The phi production rate has been measured in the energy range 0.075
Published: 1984
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39. Evidence for theF*Meson

Author: J. M. Hauptman, K. A. Derby, W. Moses, H. Yamamoto, M. Yamauchi, P. R. Robrish, A. D. Bross, A. Pevsner, A. V. Barnes, D. H. Stork, F. R. Rouse, J. Chiba, R. R. Sauerwein, X. Q. Lu, J. E. Huth, Hiroaki Aihara, J. G. Layter, A. R. Clark, D. H. Badtke, J. A. Bakken, H. S. Kaye, B. A. Barnett, Marjorie Shapiro, M. T. Ronan, A. Barbaro-Galtieri, W. M. Zhang, T. Kamae, R. R. Kofler, K. K. Kwong, J. A. J. Matthews, B. Gabioud, Orin I. Dahl, M. E. Zeller, E. M. Wang, J. N. Marx, Barry Blumenfeld, Margaret Alston-Garnjost, H. Iwasaki, R. van Tyen, M. Pripstein, W. E. Slater, W.A. Wenzel, Gilbert Shapiro, B. C. Shen, J. Hylen, C. D. Buchanan, M. L. Stevenson, Owen Chamberlain, S. C. Loken, Mitchell Wayne, R. M. Majka, C. T. Day, G. J. VanDalen, R. F. van Daalen Wetters, D. R. Nygren, Hirotsugu Fujii, D. A. Park, L. T. Kerth, L. Madansky, R. I. Koda, P. S. Martin, Philippe Eberhard, Ryoji Enomoto, W. Gorn, K. Maruyama, P. J. Oddone, R. R. Ross, R. J. Madaras, H. K. Ticho, Nicholas John Hadley, N. Toge, Peter Nemethy, Toshitsugu Fujii, S. O. Melnikoff, D. L. Fancher, R. W. Kenney, G. R. Lynch, C. Y. Chien, Werner Hofmann, C. S. Lindsey, J. W. Gary, and A. Cordier
Subjects: Physics, Particle physics, Annihilation, Meson, Electron–positron annihilation, Nuclear Theory, Hadron, General Physics and Astronomy, Elementary particle, Particle identification, Nuclear physics, Pion, High Energy Physics::Experiment, Nuclear Experiment, Boson
Abstract: Evidence for a narrow state decaying into an F meson and a photon has been obtained in e/sup +/e/sup -/ annihilation events at 29 GeV c.m. energy. This state lies 139.5 +- 8.3(stat) +- 9.7(syst) MeV above the F-meson mass and is consistent with the expected F( meson. The F mesons are identified by a peak in the K/sup +/K/sup -/..pi../sup + -/ mass at 1.948 +- 0.028 +- 0.010 GeV.
Published: 1984
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40. Search forQ=23eandQ=13eParticles Produced ine+e−Annihilations

Author: W.A. Wenzel, Gilbert Shapiro, Marjorie Shapiro, B. A. Barnett, M. L. Stevenson, S. O. Melnikoff, A. Cordier, J. A. Bakken, C. T. Day, C. S. Lindsey, A. Pevsner, Hirotsugu Fujii, S. C. Loken, D. A. Park, H. Yamamoto, L. Madansky, W. Moses, R. I. Koda, H. Videau, Barry Blumenfeld, K. Maruyama, R. W. Kenney, G. R. Lynch, P. R. Robrish, W. Gorn, J. W. Gary, F. R. Rouse, J. E. Huth, H. J. Hilke, H. K. Ticho, Margaret Alston-Garnjost, Nicholas John Hadley, A. Barbaro-Galtieri, T. Kamae, R. van Tyen, B. C. Shen, C. Y. Chien, M. E. Zeller, W. E. Slater, M. T. Ronan, Werner Hofmann, N. Toge, K. K. Kwong, Mitchell Wayne, H. Aihara, J. N. Marx, Peter Nemethy, J. Hylen, D. L. Fancher, P. S. Martin, G. J. Van Dalen, K. A. Derby, Philippe Eberhard, P. J. Oddone, Toshitsugu Fujii, R. R. Ross, Owen Chamberlain, R. J. Madaras, J. Chiba, C. D. Buchanan, X. Q. Lu, M. Pripstein, J. A. J. Matthews, R. M. Majka, D. R. Nygren, M. Yamauchi, A. D. Bross, J. M. Hauptman, A. V. Barnes, D. H. Stork, R. R. Sauerwein, J. G. Layter, W. M. Zhang, R. R. Kofler, R. F. van Daalen Wetters, L. T. Kerth, Orin I. Dahl, A. R. Clark, D. H. Badtke, B. Gabioud, and H. Iwasaki
Subjects: Physics, Nuclear physics, Quark, Range (particle radiation), Particle physics, Annihilation, Time projection chamber, General Physics and Astronomy, Elementary particle, Particle identification
Abstract: In a search for heavy Q = (2/3)e and Q = (1/3)e particles produced in e/sup +/e/sup -/ collisions at a center-of-mass energy of 29 GeV, no candidate events were found in 77 pb/sup -1/ of data collected by the time projection chamber at PEP. Upper limits are established on the inclusive cross section for the production of Q = (2/3)e and Q = (1/3) particles in the mass range 1--13 GeV/c/sup 2/, improving upon previously established limits.
Published: 1984
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41. Observation of Strangeness Correlations ine+e−Annihilation ats=29GeV

Author: W. Moses, A. R. Clark, D. H. Badtke, N. Toge, Nicholas John Hadley, J. W. Gary, M. Pripstein, Mitchell Wayne, Marjorie Shapiro, B. C. Shen, H. U. Bengtsson, S. O. Melnikoff, Peter Nemethy, J. Chiba, C. S. Lindsey, H. Yamamoto, B. A. Barnett, S. C. Loken, J. M. Hauptman, F. R. Rouse, E. M. Wang, Owen Chamberlain, L. Madansky, R. I. Koda, H. Videau, R. F. van Daalen Wetters, L. T. Kerth, B. Gabioud, R. W. Kenney, K. Maruyama, J. N. Marx, M. Yamauchi, A. D. Bross, P. R. Robrish, A. Barbaro-Galtieri, P. S. Martin, Philippe Eberhard, A. Cordier, Margaret Alston-Garnjost, R. van Tyen, J. Hylen, X. Q. Lu, H. Iwasaki, D. L. Fancher, Toshitsugu Fujii, J. E. Huth, H. K. Ticho, G. J. VanDalen, G. R. Lynch, A. Pevsner, C. T. Day, H. J. Hilke, T. Kamae, W. M. Zhang, C. Y. Chien, Werner Hofmann, R. R. Kofler, Barry Blumenfeld, J. A. J. Matthews, Hirotsugu Fujii, D. A. Park, Orin I. Dahl, J. G. Layter, A. V. Barnes, D. H. Stork, R. R. Sauerwein, R. M. Majka, D. R. Nygren, W. Gorn, P. J. Oddone, R. R. Ross, R. J. Madaras, J. A. Bakken, C. D. Buchanan, H. S. Kaye, W.A. Wenzel, Gilbert Shapiro, M. L. Stevenson, M. T. Ronan, K. K. Kwong, H. Aihara, K. A. Derby, and W. E. Slater
Subjects: Physics, Nuclear physics, Particle physics, Annihilation, General Physics and Astronomy, Strangeness
Published: 1984
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42. Measurement of the Inclusive Branching Fractionτ−→ντπ−π0+NeutralMeson(s)

Author: H. Aihara, M. Alston-Garnjost, R. E. Avery, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, D. A. Bauer, H. -U. Bengtsson, D. L. Bintinger, G. J. Bobbink, T. S. Bolognese, A. D. Bross, C. D. Buchanan, A. Buijs, D. O. Caldwell, A. R. Clark, G. D. Cowan, D. A. Crane, O. I. Dahl, K. A. Derby, J. J. Eastman, P. H. Eberhard, T. K. Edberg, A. M. Eisner, R. Enomoto, F. C. Erné, T. Fujii, J. W. Gary, W. Gorn, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X. -Q. Lu, G. R. Lynch, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, G. E. Masek, L. G. Mathis, J. A. J. Matthews, S. J. Maxfield, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Park, S. K. Park, D. E. Pellett, M. Pripstein, M. T. Ronan, R. R. Ross, F. R. Rouse, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, J. S. Steinman, M. L. Stevenson, D. H. Stork, M. G. Strauss, M. K. Sullivan, T. Takahashi, J. R. Thompson, N. Toge, S. Toutounchi, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, Z. R. Wolf, H. Yamamoto, M. Yamauchi, S. J. Yellin, C. Zeitlin, and W. -M. Zhang
Subjects: Semileptonic decay, Nuclear physics, Physics, Particle decay, Particle physics, Pion, Meson, Branching fraction, Hadron, General Physics and Astronomy, Elementary particle, Lepton
Abstract: We measure an inclusive branching fraction of (13.9 +- 2.0/sub -2.2//sup +1.9/)% for the decay tau/sup -/..--> nu../sub tau/..pi../sup -/..pi../sup 0/+nh/sup 0/ (ngreater than or equal to1), where h/sup 0/ is a ..pi../sup 0/ or an eta. The data sample, obtained with the time-projection chamber detector facility at the SLAC e/sup +/e/sup -/ storage ring PEP, corresponds to an integrated luminosity of 72 pb/sup -1/ at 29-GeV center-of-mass energy. The measured branching fraction is somewhat greater than the theoretical prediction and, with errors taken into account, could resolve the present difference between the inclusive and the sum of the exclusive tau/sup +- / branching fractions into one charged prong.
Published: 1986
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43. Erratum: Tests of models for parton fragmentation by means of three-jet events ine+e−annihilation at √s¯=29 GeV [Phys. Rev. Lett. 54, 270 (1985)]

Author: C. S. Lindsey, K. Maruyama, S. C. Loken, Peter Nemethy, H. K. Ticho, R. F. van Daalen Wetters, X. Q. Lu, A. Cordier, L. T. Kerth, J. Hylen, B. Gabioud, W. E. Slater, B. A. Barnett, Marjorie Shapiro, Mitchell Wayne, J. G. Layter, J. W. Gary, Owen Chamberlain, N. Toge, P. J. Oddone, D. R. Nygren, W. Moses, H. Yamamoto, E. M. Wang, A. Barbaro-Galtieri, R. R. Ross, D. L. Fancher, A. R. Clark, Philippe Eberhard, C. T. Day, Margaret Alston-Garnjost, R. J. Madaras, F. R. Rouse, Barry Blumenfeld, Nicholas John Hadley, K. A. Derby, R. van Tyen, S. O. Melnikoff, W. M. Zhang, C. D. Buchanan, G. J. Van Dalen, B. C. Shen, J. E. Huth, R. R. Kofler, P. R. Robrish, M. Yamauchi, G. R. Lynch, T. Kamae, W. Gorn, A. D. Bross, Orin I. Dahl, R. W. Kenney, C. Y. Chien, Werner Hofmann, H. U. Bengtsson, J. N. Marx, A. V. Barnes, D. H. Stork, R. R. Sauerwein, Toshitsugu Fujii, A. Pevsner, L. Madansky, R. I. Koda, J. M. Hauptman, J. A. Bakken, H. S. Kaye, Hirotsugu Fujii, D. A. Park, J. A. J. Matthews, M. Pripstein, M. T. Ronan, K. K. Kwong, H. Aihara, W.A. Wenzel, Gilbert Shapiro, and M. L. Stevenson
Subjects: Nuclear physics, Physics, Annihilation, Fragmentation (mass spectrometry), General Physics and Astronomy, Parton
Published: 1985
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44. Four dimensional bolus tagging imaging of pulsatile flow.

Author: Franck A, Jou L, van Tyen R, and Saloner D
Subjects: Blood Flow Velocity, Computer Simulation, Humans, Imaging, Three-Dimensional, Phantoms, Imaging, Rheology, Magnetic Resonance Imaging methods, Pulsatile Flow
Abstract: Inversion bolus tagging MR methods were used to provide a graphic depiction of the axial velocity in three spatial dimensions for pulsatile flow through complex geometries. Visualization of the flow field was readily apparent, and a train of tagged boli were depicted providing an immediate overview of the displacement of flowing fluid over the entire pulsatile cycle. Tagging efficiency obtained using adiabatic inversion pulses was improved compared to that with a windowed sinc pulse. Results from phantom experiments on steady flow were correlated with computational fluid dynamic (CFD) simulations. The use of 3D methods reduced spatial partial volume effects, and the displacement of boli in a steady flow experiment correlated well with CFD simulations. The use of adiabatic inversion pulses resulted in sharp edged inversion regions with good retention of longitudinal magnetization. However in order to keep the pulse duration short, of the order of 2-5 ms, a rather large RF amplitude had to be used. The inversion bolus tagging method is useful in visualizing the flow field in multiple levels for pulsatile fluid flowing through complex geometries, and may be useful in fluid dynamic applications.
Published: 2000
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45. Calculation of the magnetization distribution for fluid flow in curved vessels.

Author: Jou LD, van Tyen R, Berger SA, and Saloner D
Subjects: Blood Flow Velocity physiology, Carotid Arteries anatomy & histology, Computer Simulation, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Angiography instrumentation, Models, Cardiovascular, Phantoms, Imaging, Pulsatile Flow physiology, Magnetic Resonance Angiography methods
Abstract: The signal intensity in magnetic resonance angiography (MRA) images reflects both morphological and flow-related features of vascular anatomy. A thorough understanding of MRA, therefore, demands a careful analysis of flow-related effects. Computational fluid dynamics (CFD) methods are very powerful in determining flow patterns in 3D tortuous vessels for both steady and unsteady flow. Previous simulations of MRA images calculated the magnetization of flowing blood by tracking particles as they moved along flow streamlines that had been determined by a CFD calculation. This manuscript describes MRA simulations that use CFD calculations to determine magnetization variation at a fixed point and, therefore, do not require streamline tracking to calculate the distribution of magnetization in flowing fluids. This method inherently accounts for uniform particle density, avoids problems associated with tracking particles close to the wall, and is well-suited to modeling pulsatile flow.
Published: 1996
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46. Central intraluminal saturation stripe on MR angiograms of curved vessels: simulation, phantom, and clinical analysis.

Author: Saloner D, van Tyen R, Dillon WP, Jou LD, and Berger SA
Subjects: Adult, Blood Flow Velocity, Carotid Artery, Internal anatomy & histology, Carotid Artery, Internal physiology, Computer Simulation, Female, Humans, Male, Middle Aged, Phantoms, Imaging, Artifacts, Blood Vessels anatomy & histology, Magnetic Resonance Angiography
Abstract: Purpose: To investigate the appearance of reduced signal intensity in the center of blood vessels on magnetic resonance (MR) angiograms that can mimic intraluminal thrombus., Materials and Methods: Simulations and phantom studies were performed to analyze MR angiogram appearance distal to a pronounced curve., Results: Saturation effects substantially lower the signal strength in the center of the vessel relative to that at the vessel periphery. These effects appeared even though the flow was well ordered and laminar. In curved geometries, secondary flow patterns produced counter-rotating vortices, which moved the fastest-moving particles to the outside of the curve and folded the slow-moving particles to the center of the vessel., Conclusion: Imaging parameter choices that reduce saturation, such as acquisition of a two-dimensional section transverse to the vessel and through the questionable region, effectively eliminate the central hypointensity effect in vivo.
Published: 1996
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47. Cardiac-gated MR angiography of pulsatile flow: k-space strategies.

Author: Franck A, Selby K, van Tyen R, Nordell B, and Saloner D
Subjects: Artifacts, Blood Vessels anatomy & histology, Computer Simulation, Humans, Image Processing, Computer-Assisted, Leg blood supply, Models, Structural, Systole, Heart physiology, Magnetic Resonance Angiography methods, Pulsatile Flow
Abstract: Signal strength in time-of-flight magnetic resonance (MR) angiography of pulsatile flow is modulated by the time-varying intraluminal magnetization strength. The specific appearance of MR angiographic images therefore depends on the relationship of different phase-encoding steps to the pulsatile flow waveform. Cardiac-phase gating can be applied with phase-encoding reordering to acquire different regions of k-space during the desired phases of the cardiac cycle. The authors have developed a simulation program for evaluating the merits of different encoding strategies for pulsatile flow. The model was validated with phantom studies. High signal intensity relative to that in conventional MR angiographic studies can be attained with strategies that impose relatively small penalties in total acquisition time.
Published: 1995
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48. MR imaging of flow through tortuous vessels: a numerical simulation.

Author: van Tyen R, Saloner D, Jou LD, and Berger S
Subjects: Algorithms, Blood Flow Velocity physiology, Blood Pressure physiology, Blood Viscosity physiology, Carotid Arteries anatomy & histology, Carotid Artery, Common physiology, Carotid Artery, External physiology, Carotid Artery, Internal physiology, Humans, Image Enhancement methods, Magnetics, Regional Blood Flow physiology, Rheology, Carotid Arteries physiology, Computer Simulation, Magnetic Resonance Imaging methods, Models, Cardiovascular
Abstract: A novel computer simulation technique is presented that allows the calculation of images from Magnetic Resonance Angiography (MRA) studies of blood flow in realistic curving and branching two-dimensional vessel geometries. Fluid dynamic calculations provide flow streamlines through curved or branching vessels. MR simulations generate images for specific MR pulse sequence parameters. Simulations of steady flow in carotid bifurcation and carotid siphon geometries as imaged by a standard, flow-compensated, spoiled gradient echo sequence illustrate the major features seen in clinical time of flight MRA studies. The simulations provide insight into a number of artifacts encountered in MRA such as displacement artifacts, signal pile-up, truncation artifacts, and intravoxel phase dispersion.
Published: 1994
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49. Evaluation of myocardial perfusion abnormalities with gadolinium-enhanced snapshot MR imaging in humans. Work in progress.

Author: Schaefer S, van Tyen R, and Saloner D
Subjects: Adult, Aged, Contrast Media, Coronary Angiography, Coronary Disease diagnostic imaging, Coronary Disease physiopathology, Dipyridamole, Drug Combinations, Exercise Test, Gadolinium DTPA, Humans, Middle Aged, Radionuclide Imaging, Thallium Radioisotopes, Coronary Circulation, Magnetic Resonance Imaging methods, Meglumine, Organometallic Compounds, Pentetic Acid
Abstract: To determine whether myocardial perfusion abnormalities could be detected in patients with coronary artery disease by means of contrast material-enhanced magnetic resonance (MR) images, a snapshot imaging technique was used in six patients with coronary artery disease and four healthy subjects in conjunction with pharmacologic stress (dipyridamole infusion) and bolus injection of gadopentetate dimeglumine. MR images from all patients and healthy subjects were quantitatively analyzed to define spatial changes in signal intensity after administration of dipyridamole and gadopentetate dimeglumine. The resultant findings were compared with findings on thallium-201 scintigrams obtained after administration of dipyridamole and on coronary arteriograms in all patients. Nine myocardial regions supplied by stenosed arteries showed diminished levels of signal intensity after infusion of the contrast agent compared with those of normally perfused regions. These findings were in agreement with those obtained with T1-201 scintigraphy (in eight of nine regions) and arteriography. Thus, contrast-enhanced high-speed MR imaging with use of dipyridamole enabled detection of regional perfusion abnormalities in humans.
Published: 1992
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50. Application of a connected-voxel algorithm to MR angiographic data.

Author: Saloner D, Hanson WA, Tsuruda JS, van Tyen R, Anderson CM, and Lee RE
Subjects: Carotid Arteries anatomy & histology, Circle of Willis anatomy & histology, Humans, Algorithms, Blood Vessels anatomy & histology, Image Processing, Computer-Assisted methods, Magnetic Resonance Imaging methods
Abstract: A connected-voxel algorithm (CVA) that improves the contrast and conspicuity of blood vessels in maximum-intensity-projection (MIP) magnetic resonance (MR) angiography is described. Images from a variety of anatomic regions in healthy volunteers were calculated with either an MIP procedure alone or with data that had first been processed with the CVA. A low-signal-intensity threshold is first applied to separate groups of voxels associated with different vessels from one another and to eliminate the contribution from low-intensity stationary material. The remaining voxels are grouped by a connectivity criterion into discrete "objects." Vessels are represented by extended objects, and small objects are discarded. The CVA, therefore, reduces the full three-dimensional data set into a small number of discrete objects. It is a powerful technique that can be used to remove signal from vessels overlying the vessel of interest, to separate objects representing arterial flow from those representing venous flow, to eliminate flow artifact from projection images, and to more completely retain signal within the vascular lumen. This technique has been successfully demonstrated with MR angiography in healthy volunteers.
Published: 1991
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