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86
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Nuevos aspectos en el estudio de la particula D en el experimento FOCUS de Fermilab
The purpose of this work is to improve the reconstruction techniques of the decays of the particles that contain charm in the quark composition using the information of the Target Silicon Detector of the experiment E831 (FOCUS). That experiment runs during 1997 to 1998 in Fermilab National Laboratory. The objective of the experiment was improving the understanding of the particles that contain charm. Adding the Target Silicon Detector information in the reconstruction process of the primary vertex the position error. This reduction produces an improvement in the mass signal and the knowledge of the charm particles properties. This ad to the possibility's that in other analysis will use the techniques developed in this work.
Date:
January 1, 2005
Creator:
Quinones Gonzalez, Jose A. & /Puerto Rico U., Mayaguez
Object Type:
Report
System:
The UNT Digital Library
2005 BRAC Commission Final COBRA Run - USA-0234v2 RC Transformation in Puerto Rico AFRC Mayaguez, PR
2005 BRAC Commission Final COBRA Run - USA-0234v2 RC Transformation in Puerto Rico AFRC Mayaguez, PR - 41 - RC Transformation in Puerto Rico\Mayaguez
Date:
March 29, 2006
Creator:
United States. Defense Base Closure and Realignment Commission.
Object Type:
Text
System:
The UNT Digital Library
Development of Nanofluidic Cells for Ultrafast X-ray Studies of Water
In order to study the molecular structure and dynamics of liquid water with soft x-ray probes, samples with nanoscale dimensions are needed. This paper describes a simple method for preparing nanofluidic water cells. The idea is to confine a thin layer of water between two silicon nitride windows. The windows are 1 mm x 1 mm and 0.5 mm x 0.5 mm in size and have a thickness of 150 nm. The thickness of the water layer was measured experimentally by probing the infrared spectrum of water in the cells with a Fourier Transform InfraRed (FTIR) apparatus and from soft x-ray static measurements at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory. Water layers ranging from 10 nm to more than 2 {micro}m were observed. Evidence for changes in the water structure compared to bulk water is observed in the ultrathin cells.
Date:
August 23, 2006
Creator:
Irizarry, Melvin E. & /Puerto Rico U., Mayaguez /SLAC
Object Type:
Article
System:
The UNT Digital Library
Minority On-Line Information Service (MOLIS): A minority research and education information service. Final report for Department of Energy Grant No. DE-FG02-90ER75602
MOLIS is an online database of minority institutions, and is used by federal agencies to identify peer reviewers and by majority institutions to identify possible collaborations and sub-contracts. MOLIS includes in-depth information about the research and educational capabilities of Historically Black Colleges and Universities (HBCUs), Hispanic Serving Institutions (HSIs), and Tribal Colleges. Included with this report are several annual progress reports, a list of all minority institutions currently on MOLIS, a list of outreach activities, etc.
Date:
December 1, 2000
Creator:
Rodman, John A.
Object Type:
Report
System:
The UNT Digital Library
Enteric viruses in a mangrove lagoon, survival and shellfish incidence
Mangrove oysters (Crassostrea rhizophorae) were screened for enteric viruses. For 18 months oysters were collected from Cano Boqueron, a tropical mangrove lagoon on the southwest coast of Puerto Rico. This popular tourist resort has two primary sewage treatment plants which service 158 single family cabanas. In spite of the heavy seasonal input of sewage to Cano Boqueron and high densities of fecal coliform bacteria, enteric viruses were not detected in shellfish meat. Because no viruses were detected in the oysters, a virus survival study was performed. Poliovirus type 1 was placed in diffusion chambers in situ at two sites in Cano Boqueron. More than 95% of the poliovirus inactivation occurred within 24 h. Virus inactivation was significantly different by site, indicating different inactivation rates within the lagoon. Chamber studies done simultaneously with Escherichia coli did not reveal differences between sites. It is suggested that the sewage effluent had an antiviral effect in the absence of an antibacterial effect. This study demonstrates the importance for establishing microbial contamination standards for shellfish growing waters in the tropics based upon in situ studies with tropical species, e.g. mangrove oyster.
Date:
Spring 1988
Creator:
Lopez de Cardona, I.; Bermudez, M.; Billmire, E. & Hazen, T. C.
Object Type:
Report
System:
The UNT Digital Library
A Measurement of the D+(s) lifetime
A high statistics measurement of the D{sub s}{sup +} lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. They describe the analysis of the two decay modes, D{sub s}{sup +} {yields} {phi}(1020){pi}{sup +} and D{sub s}{sup +} {yields} {bar K}*(892){sup 0}K{sup +}, used for the measurement. The measured lifetime is 507.4 {+-} 5.5(stat.) {+-} 5.1(syst.) is using 8961 {+-} 105 D{sub s}{sup +} {yields} {phi}(1020){pi}{sup +} and 4680 {+-} 90 D{sub s}{sup +} {yields} {bar K}*(892){sup 0} K{sup +} decays. This is a significant improvement over the present world average.
Date:
April 1, 2005
Creator:
Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
Object Type:
Article
System:
The UNT Digital Library
Defect-related internal dissipation in mechanical resonators and the study of coupled mechanical systems.
Understanding internal dissipation in resonant mechanical systems at the micro- and nanoscale is of great technological and fundamental interest. Resonant mechanical systems are central to many sensor technologies, and microscale resonators form the basis of a variety of scanning probe microscopies. Furthermore, coupled resonant mechanical systems are of great utility for the study of complex dynamics in systems ranging from biology to electronics to photonics. In this work, we report the detailed experimental study of internal dissipation in micro- and nanomechanical oscillators fabricated from amorphous and crystalline diamond materials, atomistic modeling of dissipation in amorphous, defect-free, and defect-containing crystalline silicon, and experimental work on the properties of one-dimensional and two-dimensional coupled mechanical oscillator arrays. We have identified that internal dissipation in most micro- and nanoscale oscillators is limited by defect relaxation processes, with large differences in the nature of the defects as the local order of the material ranges from amorphous to crystalline. Atomistic simulations also showed a dominant role of defect relaxation processes in controlling internal dissipation. Our studies of one-dimensional and two-dimensional coupled oscillator arrays revealed that it is possible to create mechanical systems that should be ideal for the study of non-linear dynamics and localization.
Date:
January 1, 2007
Creator:
Friedmann, Thomas Aquinas; Czaplewski, David A.; Sullivan, John Patrick; Modine, Normand Arthur; Wendt, Joel Robert; Aslam, Dean (Michigan State University, Lansing, MI) et al.
Object Type:
Report
System:
The UNT Digital Library
Battery-free Wireless Sensor Network For Advanced Fossil-Fuel Based Power Generation
This report summarizes technical progress achieved during the project supported by the Department of Energy under Award Number DE-FG26-07NT4306. The aim of the project was to conduct basic research into battery-free wireless sensing mechanism in order to develop novel wireless sensors and sensor network for physical and chemical parameter monitoring in a harsh environment. Passive wireless sensing platform and five wireless sensors including temperature sensor, pressure sensor, humidity sensor, crack sensor and networked sensors developed and demonstrated in our laboratory setup have achieved the objective for the monitoring of various physical and chemical parameters in a harsh environment through remote power and wireless sensor communication, which is critical to intelligent control of advanced power generation system. This report is organized by the sensors developed as detailed in each progress report.
Date:
February 28, 2011
Creator:
Jia, Yi
Object Type:
Report
System:
The UNT Digital Library
Search for T violation in charm meson decays
Using data from the FOCUS (E831) experiment, they have searched for T violation in charm meson decays using the four-body decay channels D{sup 0} {yields} K{sup -}K{sup +} {pi}{sup -}{pi}{sup +}, D{sup +} {yields} K{sub S}{sup 0}K{sup +}{pi}{sup -}{pi}{sup +}, and D{sub s}{sup +} {yields} K{sub S}{sup 0}K{sup +}{pi}{sup -}{pi}{sup +}. The T violation asymmetry is obtained using triple-product correlations and assuming the validity of the CPT theorem. They find the asymmetry values to be A{sub T{sub viol}}(D{sup 0}) = 0.010 {+-} 0.057(stat.) {+-} 0.037(syst.), A{sub T{sub viol}}(D{sup +}) = 0.023 {+-} 0.062(stat.) {+-} 0.022(syst.), and A{sub T{sub viol}}(D{sub s}{sup +}) = -0.036 {+-} 0.067(stat.) {+-} 0.023(syst.). Each measurement is consistent with no T violation. New measurements of the CP asymmetries for some of these decay modes are also presented.
Date:
June 1, 2005
Creator:
Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
Object Type:
Article
System:
The UNT Digital Library
GRPANL: a program for deconvoluting and interpreting complex peak clusters
GRPANL (GRouP ANaLysis) is a general-purpose peak fitting program that first determines gamma-ray and x-ray energies and intensities for specified peaks or clusters of peaks in a spectrum and then proceeds to interpret these results, determining both the radioisotopes detected and the amounts of each in the sample. Versions of the program are now running on the Digital Equipment Corporation (DEC) VAX and PDP-11 computers. The code has several unique capabilities for deconvoluting and interpreting difficult analytical situations that other codes usually cannot handle.
Date:
March 23, 1984
Creator:
Gunnink, R.; Ruhter, W. D. & Niday, J. B.
Object Type:
Article
System:
The UNT Digital Library
Study of the D0 ---> K+ K- pi+ pi-
Using data from the FOCUS (E831) experiment at Fermilab, the authors present a new measurement for the Cabibbo-suppressed decay mode D{sup 0} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}. They measure: {Lambda}(D{sup 0} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{pi}{sup +}) = 0.0295 {+-} 0.0011 {+-} 0.0008. An amplitude analysis has been performed in order to determine the resonant substructure of this decay mode. The dominant components are the decays D{sup 0} {yields} K{sub 1}(1270){sup +} K{sup -}, D{sup 0} {yields} K{sub 1}(1400){sup +}K{sup -} and D{sup 0} {yields} {rho}(770){sup 0}{phi}(1020).
Date:
November 1, 2004
Creator:
Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Gobel, C. et al.
Object Type:
Article
System:
The UNT Digital Library
COMSYS: a computer code to determine fission product inventories and related quantities
None
Date:
January 1, 1973
Creator:
Gileadi, A. E. & Musalem, A.
Object Type:
Article
System:
The UNT Digital Library
Transient Grating in a Knbo{Sub 3}/Ktao{Sub 3} Superlattice
Time-resolved degenerate-four-wave-mixing (DFWM) techniques have been used to characterize the nonlinear optical response of a KNbO{sub 3}/KTaO{sub 3} superlattice grown by pulsed laser deposition on a 1 mm thick, (001)-oriented KTaO{sub 3} substrate. With a 30 psec pulsed laser, the difference in the nonlinear optical response between bulk KTaO{sub 3} and the superlattice was measured. Results indicate that a significant contribution to the response signal is due to the KNbO{sub 3} superlattice. The {chi}{sup (3)} value was estimated to have increased by 2 orders of magnitude compared to the bulk crystal.
Date:
June 1, 1998
Creator:
Liu, H.; Fernandez, F.; Jia, W. & Boatner, L. A.
Object Type:
Report
System:
The UNT Digital Library
Biological Ocean Margins Program. Active Microbes Responding to Inputs from the Orinoco River Plume. Final Report
The overall goal of the proposed work is to identify the active members of the heterotrophic community involved in C and N cycling in the perimeter of the Orinoco River Plume (ORP), assess their spatial distribution, quantify their metabolic activity, and correlate these parameters to plume properties such as salinity, organic matter content and phytoplankton biomass.
Date:
January 28, 2013
Creator:
Corredor, Jorge E.
Object Type:
Report
System:
The UNT Digital Library
Mathematics and Statistics Research Department progress report for period ending June 30, 1979. [ORNL]
This is the twenty-second in the series of progress reports of the Mathematics and Statistics Research Department and its predecessor organizations. Part A reports research progress in biomedical and environmental applications, materials science applications, model development and evaluation, moving-boundary problems, multivariate multipopulation classification, numerical linear algebra, risk analysis, and complementary areas. The results of collaboration with other researchers on problems in biology, chemistry, energy, engineering, environmental sciences, geology, health and safety research, information sciences, and material sciences are recorded in Part B. Parts C, D, and E contain short accounts of educational activities, lists of written and oral presentations of research results, and a list of other professional activities in which the staff was engaged. Although a few results are shown, the reports in this volume are only of extended abstract length. One may expect completed research to be reported in the usual channels. 6 figures, 2 tables. (RWR)
Date:
September 1, 1979
Creator:
Gardiner, D.A.; Beauchamp, J.J.; Gray, L.J.; Lever, W.E. & Shepherd, D.E.
Object Type:
Report
System:
The UNT Digital Library
Nondestructive low-energy photon analysis of environmental samples
Low-energy photons that accompany the decay of alpha- or beta-emitting radionuclides (e.g., /sup 241/Am, /sup 210/Pb, and /sup 238/U-/sup 234/Th) may be used to quantify concentrations of these radionuclides in environmental samples. Previous attempts to quantify these low-energy photons have had limited success because of the uncertainty associated with photon attenuation in samples of variable matrix composition. A method for directly measuring and applying the self-absorption correction factor is presented. Results obtained by this nondestructive technique for counting low-energy photons are in agreement with values obtained from intracalibrated samples using radiochemical separations and alpha or beta analysis. 8 references, 1 figure, 3 tables.
Date:
January 1, 1984
Creator:
Larsen, Ingvar L.; Cutshall, Norman H. & Olsen, Curtis R.
Object Type:
Report
System:
The UNT Digital Library
BRAC 2005 Report to the Base Closure and Realignment Commission: Army Justification Book
Disregard Restriction Header and Footer - RC Transformation in Puerto Rico - Impacted Sites: AFRC Ceiba; AFRC Fort Allen; AFRC Mayaguez; AFRC Fort Buchanan
Date:
June 10, 2005
Creator:
United States. Department of Defense.
Object Type:
Book
System:
The UNT Digital Library
History of Dredging and Filling of Lagoons in the San Juan Area, Puerto Rico
Abstract: Laguna La Torrecilla, Laguna de Pinones, Laguna San Jose, and Laguna del Condado, in the San Juan, Puerto Rico area, are located within a metropolitan area of more than 1 million people. Bathymetric maps made during the study, in 1973, showed that Lagunas La Torrecilla, San Jose, and del Condado have been modified by dredging and filling; whereas, Laguna de Pinones has remained in a near natural state. Laguna La Torrecilla has been dredged to a depth, in places, of about 18 metres, and Lagunas San Jose and del Condado, in places to about 11 meters. Dredging in the San Juan lagoons has been harmful, beneficial, and in a few instances has had little or no noticeable effect on the water quality. Usually, dredging in the connecting canals has been beneficial if the water entering the lagoons through the canals was of better quality than the water in the lagoon. Dredging in the mouths of lagoons has been beneficial; whereas, filling or blocking the mouths has been harmful.
Date:
September 1976
Creator:
Ellis, S. R.
Object Type:
Report
System:
The UNT Digital Library
5th Biotechnological Investigations Ocean Margins Program
BI-OMP supports DOE's mission in Climate Change Research. The program provides the fundamental understanding of the linkages between carbon and nitrogen cycles in ocean margins. Researchers are providing a mechanistic understanding of these cycles, using the tools of modern molecular biology. The models that will allow policy makers to determine safe levels of greenhouse gases for the Earth System.
Date:
January 8, 2004
Creator:
Massol, Arturo & Buxeda, Rosa
Object Type:
Article
System:
The UNT Digital Library
New charm results from FOCUS
New results from the photoproduction experiment FOCUS are reported: Dalitz plot analysis, semileptonic form factor ratios and excited meson spectroscopy. The author reports on three new results from the photoproduction experiment FOCUS: the first Dalitz plot analysis of charm meson decays using the K-matrix approach[ 1], new measurements of the D{sub s}{sup +} {yields} {delta}(1020) {mu}{sup +}{nu} form factor ratios [2], and new measurements on L=1 excited meson spectroscopy [3], i.e., precise measurements of the masses and widths of the D*{sub 2}{sup +} and D*{sub 2}{sup 0} mesons, and evidence for broad states decaying to D{sup +}{pi}{sup -}, D{sup 0}{pi}{sup +} (the first such evidence in D{sup 0}{pi}{sup +}). The data for this paper were collected in the Wideband photoproduction experiment FOCUS during the Fermilab 1996-1997 fixed-target run.
Date:
December 1, 2004
Creator:
Bianco, Stefano
Object Type:
Article
System:
The UNT Digital Library
Radionuclides in plankton from the South Pacific Basin
We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 10/sup 4/. We participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northwest Laboratories sampled air, water, rain, and fallout. We were able to measure concentrations in plankton of the naturally-occurring radionuclides /sup 7/Be, /sup 40/K, and the U and Th series, and we believe that we have detected low levels of /sup 144/Ce and /sup 95/Nb in seven samples ranging as far south as 68/sup 0/. Biological identification of the plankton suggests a possible correlation between radionuclide concentration and the protozoa content of the samples. 7 references, 5 figures.
Date:
March 23, 1984
Creator:
Marsh, K.V. & Buddemeier, R.W.
Object Type:
Report
System:
The UNT Digital Library
Development and analysis of a linearly segmented CPC collector for industrial steam generation
This study involves the design, analysis and construction of a modular, non-imaging, trough, concentrating solar collector for generation of process steam in a tropical climate. The most innovative feature of this concentrator is that the mirror surface consists of long and narrow planar segments placed inside sealed low-cost glass tubes. The absorber is a cylindrical fin inside an evacuated glass tube. As an extension of the same study, the optical efficiency of the segmented concentrator has been simulated by means of a Monte-Carlo Ray-Tracing program. Laser Ray-Tracing techniques were also used to evaluate the possibilities of this new concept. A preliminary evaluation of the experimental concentrator was done using a relatively simple method that combines results from two experimental measurements: overall heat loss coefficient and optical efficiency. A transient behaviour test was used to measure the overall heat loss coefficient throughout a wide range of temperatures.
Date:
June 1, 1980
Creator:
Figueroa, Jose Alberto Atienza
Object Type:
Report
System:
The UNT Digital Library
Dalitz plot analysis of the D+ ---> K- pi+ pi+ decay in the FOCUS experiment
Using data collected by the high energy photoproduction experiment FOCUS at Fermilab we performed a Dalitz plot analysis of the Cabibbo favored decay D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +}. This study uses 53653 Dalitz-plot events with a signal fraction of {approx} 97%, and represents the highest statistics, most complete Dalitz plot analysis for this channel. Results are presented and discussed using two different formalisms. The first is a simple sum of Breit-Wigner functions with freely fitted masses and widths. It is the model traditionally adopted and serves as comparison with the already published analyses. The second uses a K-matrix approach for the dominant S-wave, in which the parameters are fixed by first fitting K{pi} scattering data and continued to threshold by Chiral Perturbation Theory. We show that the Dalitz plot distribution for this decay is consistent with the assumption of two body dominance of the final state interactions and the description of these interactions is in agreement with other data on the K{pi} final state.
Date:
May 1, 2007
Creator:
Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
Object Type:
Article
System:
The UNT Digital Library
DENSE MULTIPHASE FLOW SIMULATION: CONTINUUM MODEL FOR POLY-DISPERSED SYSTEMS USING KINETIC THEORY
The overall objective of the project was to verify the applicability of the FCMOM approach to the kinetic equations describing the particle flow dynamics. For monodispersed systems the fundamental equation governing the particle flow dynamics is the Boltzmann equation. During the project, the FCMOM was successfully applied to several homogeneous and in-homogeneous problems in different flow regimes, demonstrating that the FCMOM has the potential to be used to solve efficiently the Boltzmann equation. However, some relevant issues still need to be resolved, i.e. the homogeneous cooling problem (inelastic particles cases) and the transition between different regimes. In this report, the results obtained in homogeneous conditions are discussed first. Then a discussion of the validation results for in-homogeneous conditions is provided. And finally, a discussion will be provided about the transition between different regimes. Alongside the work on development of FCMOM approach studies were undertaken in order to provide insights into anisotropy or particles kinetics in riser hydrodynamics. This report includes results of studies of multiphase flow with unequal granular temperatures and analysis of momentum re-distribution in risers due to particle-particle and fluid-particle interactions. The study of multiphase flow with unequal granular temperatures entailed both simulation and experimental studies of two …
Date:
August 31, 2011
Creator:
Bogere, Moses
Object Type:
Report
System:
The UNT Digital Library