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PROSPECTS FOR PENTAQUARK SEARCHES IN E+D- ANNIHILATIONS AND VV COLLISIONS. (open access)

PROSPECTS FOR PENTAQUARK SEARCHES IN E+D- ANNIHILATIONS AND VV COLLISIONS.

Recent strong experimental evidence of a narrow exotic S = +1 baryon resonance, {Theta}{sup +}, suggests the existence of other exotic baryons. We discuss the prospects of confirming earlier experimental evidence of {Theta}{sup +} and the observation of additional hypothetical exotic baryons in e{sup +}e{sup -} annihilations and {gamma}{gamma} collisions at LEP and B Factories.
Date: June 28, 2004
Creator: ARMSTRONG,S.; MELLADO,B. & WU,S. L.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 106, No. 76, Ed. 1 Monday, June 28, 2004 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 76, Ed. 1 Monday, June 28, 2004

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: June 28, 2004
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
An Investigation of Solid-State Amidization and Imidization Reactions in Vapor Deposited Poly (amic acid) (open access)

An Investigation of Solid-State Amidization and Imidization Reactions in Vapor Deposited Poly (amic acid)

The condensation polymerization reaction of 4,4'-oxydianiline (ODA) with pyromellitic dianhydride (PMDA) to form poly(amic acid) and the subsequent imidization reaction to form polyimide were investigated for films prepared using vapor deposition polymerization techniques. Fourier-transform infrared spectroscopy (FT-IR), thermal analysis, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) of films at different temperatures indicate that additional solid-state polymerization occurs prior to imidization reactions. Experiments reveal that, upon vapor deposition, poly(amic acid) oligomers form that have a number-average molecular weight of about 1500 Daltons. Between 100 - 130 C these chains undergo additional condensation reaction to form slightly higher molecular weight oligomers. Calorimetry measurements show that this reaction is exothermic ({Delta}H {approx} -30 J/g) with an activation energy of about 120 kJ/mol. Experimental reaction enthalpies are compared to results from ab initio molecular modeling calculations to estimate the number of amide groups formed. At higher temperatures (150 - 300 C) imidization of amide linkages occurs as an endothermic reaction ({Delta}H {approx} +120 J/g) with an activation energy of about 130 kJ/mol. Solid-state kinetics were found to depend on reaction conversion as well as the processing conditions used to deposit films.
Date: June 28, 2004
Creator: Anthamatten, M; Letts, S A; Day, K; Cook, R C; Gies, A P; Hamilton, T P et al.
Object Type: Article
System: The UNT Digital Library
Barrier rf systems in synchrotrons (open access)

Barrier rf systems in synchrotrons

Recently, many interesting applications of the barrier RF system in hadron synchrotrons have been realized. A remarkable example of this is the development of longitudinal momentum mining and implementation at the Fermilab Recycler for extraction of low emittance pbars for the Tevatron shots. At Fermilab, we have barrier RF systems in four different rings. In the case of Recycler Ring, all of the rf manipulations are carried out using a barrier RF system. Here, the author reviews various uses of barrier rf systems in particle accelerators including some new schemes for producing intense proton beam and possible new applications.
Date: June 28, 2004
Creator: Bhat, Chandra M.
Object Type: Article
System: The UNT Digital Library
Observations of Anisotropic Ion Temperature in the NSTX Edge during RF Heating (open access)

Observations of Anisotropic Ion Temperature in the NSTX Edge during RF Heating

A new spectroscopic diagnostic with both toroidal and poloidal views has been implemented in the edge of the National Spherical Torus Experiment (NSTX). This edge rotation diagnostic (ERD) was designed to measure the velocity and temperature of ions. The intersection of the diagnostic sightlines with the intrinsic emission shell provides the localization of the measurement. There are 7 toroidally directed views and 6 poloidally directed views of the outboard plasma edge. The poloidal view is {approx}20 cm (toroidally) from the RF antenna, and the toroidal view is {approx}2 m away. The sightlines are nearly tangent to the flux surfaces. The C{sup 2+} triplet near 4651 {angstrom} and the He{sup +} line at 4685 {angstrom} are measured. In the results presented here, helium is the bulk, ''working'' ion of the discharge. The NSTX is a large spherical tokamak with a major radius of 0.85 m and a minor radius of 0.65 m. The outer walls and center-stack are lined with protective carbon tiles. Pulse lengths for these NSTX discharges are {approx} 600 ms, with an on-axis toroidal magnetic field of {approx} 0.3 T. The plasma current is 500 kA. The on-axis electron temperature and density are {le} 2 keV and {approx} …
Date: June 28, 2004
Creator: Biewer, T. M.; Bell, R. E.; Ryan, P. M. & Wilson, J. R.
Object Type: Report
System: The UNT Digital Library
Homeland Security: Unmanned Aerial Vehicles and Border Surveillance (open access)

Homeland Security: Unmanned Aerial Vehicles and Border Surveillance

This report examines the strengths and limitations of deploying UAVs along the borders and related issues for Congress.
Date: June 28, 2004
Creator: Bolkcom, Christopher
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 243, Ed. 1 Monday, June 28, 2004 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 243, Ed. 1 Monday, June 28, 2004

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: June 28, 2004
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Perry Daily Journal (Perry, Okla.), Vol. 111, No. 124, Ed. 1 Monday, June 28, 2004 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 111, No. 124, Ed. 1 Monday, June 28, 2004

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: June 28, 2004
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
Welfare Recipients and Workforce Laws (open access)

Welfare Recipients and Workforce Laws

None
Date: June 28, 2004
Creator: Burke, Vee
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, June 28, 2004 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, June 28, 2004

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: June 28, 2004
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 82, No. 210, Ed. 1 Monday, June 28, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 82, No. 210, Ed. 1 Monday, June 28, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 28, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Clean Water Act Issues in the 108th Congress (open access)

Clean Water Act Issues in the 108th Congress

Prospects for legislative initiatives to comprehensively amend the Clean Water Act have stated for some time over whether and exactly how to change the law, and Congress has recently focused legislative attention on narrow bills to extend or modify selected Clean Water Act programs, rather than taking up comprehensive proposals. This report contains information on the issues and actions regarding the Clean Water Act addressed in the 108th Congress.
Date: June 28, 2004
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Mass and Density, Criticality Relationships, Generalized (open access)

Mass and Density, Criticality Relationships, Generalized

As it relates to neutron transport calculations, in an earlier report I defined scaling laws relating reactivity or criticality to the mass, density and dimensions of geometrically simple systems. Here I generalize these scaling laws to any geometry. These are well known relationships that allow the variation of critical mass versus density and/or dimensions to be written in a simple analytical form. With these relationships anyone can quickly estimate the critical mass corresponding to any given density, using nothing more complicated than a hand calculator. In addition I point out that these scaling laws can be used to easily predict the sensitivity of a system's K-eff to variations in density and/or dimensions. These relationships have appeared extensively in the literature for over 50 years, but seem to be periodically forgotten. As such, this report is not intended to present any new information, but rather it is intended merely to refresh our memories. The main idea is that you do not have to perform neutron transport calculations every time a parameter of a system is changed; instead you can use simple scaling laws to determine what will change. Here is a quick summary of results.
Date: June 28, 2004
Creator: Cullen, D E
Object Type: Report
System: The UNT Digital Library
Iron Phosphate Glasses: An Alternative for Vitrifying Certain Nuclear Wastes (open access)

Iron Phosphate Glasses: An Alternative for Vitrifying Certain Nuclear Wastes

The unusual properties and beneficial characteristics of iron phosphate glasses, as viewed from the standpoint of alternative glasses for vitrifying nuclear and hazardous wastes (which contain components that make them poorly suited for vitrification in borosilicate glass), have been investigated by the University of Missouri-Rolla with support from the Environmental Management Science Program (EMSP), DOE [DEFG07- 96ER45618]. During the past year, the corrosion resistance of Inconel 690 and 693 coupons submerged in an iron phosphate melt at 1050 C for up to 155 days has been investigated to determine whether iron phosphate glasses could be melted in a Joule Heated Melter (JHM) equipped with such electrodes in the same manner as now being used to melt borosilicate glass. Substituting iron phosphate glasses for borosilicate glasses could significantly reduce the time and cost for clean up due to the higher waste loading possible in iron phosphate glass. The iron phosphate melt, which contained 30 wt% of the Hanford Low Activity Waste (LAW), did not corrode the Inconel 690 to any greater extent than what has been reported for Inconel 690 electrodes in the borosilicate melt in the JHM at the Defense Waste Processing Facility. Furthermore, Inconel 693 appeared to be an …
Date: June 28, 2004
Creator: Day, Delbert E. & Kim, Cheol-Woon
Object Type: Report
System: The UNT Digital Library
Np Analysis of Freshly Separated Material (open access)

Np Analysis of Freshly Separated Material

Np analysis has historically relied upon the Pa/Np secular equilibrium for quantitative results. The Savannah River Site has recently undertaken a mission concerning Np. In this application, Np is separated from Pa, packaged, possibly mixed with other batches, and assayed. The fresh separation and mixing of batches prevents the use of the Pa133 prodigy peaks for assay. This effort was a developmental project novel in the DOE complex. This paper discusses the challenges encountered in the design of instrumentation to assay Np directly. The most abundant Np peak that is unfettered by Pa prodigy, Am, or other SNM materials is the 29.6keV. Quantitative measurement of such a low energy peak presents significant problems with attenuation, Compton effects, and other such issues that arise while trying to maximize the effects of low energy peaks. The solutions rely on exploiting the ''tried and true'' methods with regard to shielding, detector technology, and calibration techniques, but wit h a very low energy perspective. The results are intriguing and, with some assumptions regarding sample homogeneity, quantitative within normal MC and A statistics.
Date: June 28, 2004
Creator: HODGE, CHRISTOPHERA.
Object Type: Article
System: The UNT Digital Library
POGAL B-Axis Motor Test (open access)

POGAL B-Axis Motor Test

The Aerotech model S-180-69-A, a brushless DC motor of slotless design, was selected as the B-axis drive for the Precision Optical Grinder and Lathe (POGAL). It is common knowledge that a slotless motor will have effectively no magnetic cogging and much less torque ripple than a traditional slot-type motor. It is logical to believe that the radial and axial forces generated between the rotor and stator would also be smaller for a slotless design. This is important when a frameless motor is directly coupled to the axis, as these forces directly influence the axis and affect its error motion. It is the purpose of this test to determine the radial and axial forces generated by the Aerotech motor and to estimate their effect on the error motion of the axis using a mathematical model of the hydrostatic bearing being designed for POGAL. The test results combined with a mathematical model of the POGAL B axis indicate that the directly coupled Aerotech motor will be quite acceptable. In the radial direction, the residual motor force, after subtracting out the one-cycle force, could cause sub nanometer level error motion at the tool point. The axial direction is not in a sensitive direction …
Date: June 28, 2004
Creator: Hale, L C & Wulff, T A
Object Type: Report
System: The UNT Digital Library
Federal Homeland Security Research and Development Funding: Issues of Data Quality (open access)

Federal Homeland Security Research and Development Funding: Issues of Data Quality

None
Date: June 28, 2004
Creator: Knezo, Genevieve J.
Object Type: Report
System: The UNT Digital Library
Frequency Selective Surfaces as Near Infrared Electro-Magnetic Filters for Thermophotovoltaic Spectral Control (open access)

Frequency Selective Surfaces as Near Infrared Electro-Magnetic Filters for Thermophotovoltaic Spectral Control

Frequency selective surfaces (FSS) effectively filter electromagnetic radiation in the microwave band (1 mm to 100 mm). Interest exists in extending this technology to the near infrared (1 {micro}m to 10 {micro}m) for use as a filter of thermal radiation in thermophotovoltaic (TPV) direct energy conversion. This paper assesses the ability of FSS to meet the strict spectral performance requirements of a TPV system. Inherent parasitic absorption, which is the result of the induced currents in the FSS metallization, is identified as a significant obstacle to achieving high spectral performance.
Date: June 28, 2004
Creator: Kristensen, RF; Beausang, JF & DePoy, DM
Object Type: Article
System: The UNT Digital Library
New waveguide-type HOM damper for ALS storage ring cavities. (open access)

New waveguide-type HOM damper for ALS storage ring cavities.

The ALS storage ring 500 MHz RF system uses two re-entrant accelerating cavities powered by a single 320kW PHILLIPS YK1305 klystron. During several years of initial operation, the RF cavities were not equipped with effective passive HOM damper systems. Longitudinal beam stability was achieved through cavity temperature control and the longitudinal feedback system (LFB), which was often operating at the edge of its capabilities. As a result, longitudinal beam stability was a significant operations issue at the ALS. During two consecutive shutdown periods (April 2002 and 2003) we installed E-type HOM dampers on the main and third harmonic cavities. These devices dramatically decreased the Q-values of the longitudinal anti-symmetric HOM modes. The next step is to damp the rest of the longitudinal HOM modes in the main cavities below the synchrotron radiation damping level. This will hopefully eliminate the need for the LFB and set the stage for a possible increase in beam current. The ''waveguide'' type of HOM damper was the only option that didn't significantly compromise the vacuum performance of the RF cavity. The design process and the results of the low level measurements of the new waveguide dampers are presented in this paper.
Date: June 28, 2004
Creator: Kwiatkowski, Slawomir; Baptiste, Kenneth & Julian, James
Object Type: Article
System: The UNT Digital Library
Incremental Termination of Safeguards during D and D Activities (open access)

Incremental Termination of Safeguards during D and D Activities

The Savannah River Site (SRS) is currently in the process of Deactivation and Decommissioning (D and D) several process areas. These activities are expected to continue over the next several years. This paper addresses the Material Control and Accountability (MC and A) guidelines that have been developed for D and D activities at SRS. The MC and A D and D guidelines developed address topical areas that can impact activities associated with facility closures. Several areas of concern are: material hold-up, hold-up measurements, nuclear material access and surveillance requirements, updating accountability records, transition to lower category MBAs, usage of administrative MBAs, and the termination of safeguards. The goal of the guidelines were to stress the MC and A programmatic requirements identified within the Department of Energy Manual for the Accountability of Nuclear Materials while managing the potential impact on the D and D activities in an identified area.
Date: June 28, 2004
Creator: LUDWICK, DONALDR.
Object Type: Article
System: The UNT Digital Library
DART y el Trinity Railway Express te llevan a grandes espectáculos en el American Airlines Center (open access)

DART y el Trinity Railway Express te llevan a grandes espectáculos en el American Airlines Center

News release detailing DART and TRE transportation options to the American Airlines Center in Dallas and advertising entertainment hosted at the venue.
Date: June 28, 2004
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Ticket to an Active Lifestyle (open access)

Ticket to an Active Lifestyle

News release about DART services helping senior citizens live more active lifestyle.
Date: June 28, 2004
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Electrochemical Sensors for PEMFC vehicles (open access)

Electrochemical Sensors for PEMFC vehicles

None
Date: June 28, 2004
Creator: Martin, L. P. & Glass, R. S.
Object Type: Report
System: The UNT Digital Library
The Core of NGC 6240 from Keck Adaptive Optics and HST NICMOS Observations (open access)

The Core of NGC 6240 from Keck Adaptive Optics and HST NICMOS Observations

We present results of near infrared imaging of the disk-galaxy-merger NGC 6240 using adaptive optics on the Keck II Telescope and reprocessed archival data from NICMOS on the Hubble Space Telescope. Both the North and South nuclei of NGC 6240 are clearly elongated, with considerable sub-structure within each nucleus. In K' band there are at least two point-sources within the North nucleus; we tentatively identify the south-western point-source within the North nucleus as the position of one of the two AGNs. Within the South nucleus, the northern subnucleus is more highly reddened. Based upon the nuclear separation measured at 5 GHz, we suggest that the AGN in the South nucleus is still enshrouded in dust at K' band, and is located slightly to the north of the brightest point in K' band. Within the South nucleus there is strong H{sub 2} 1-0 S(1) line emission from the northern sub-nucleus, contrary to the conclusions of previous seeing-limited observations. Narrowband H{sub 2} emission-line images show that a streamer or ribbon of excited molecular hydrogen connects the North and South nuclei. We suggest that this linear feature corresponds to a bridge of gas connecting the two nuclei, as seen in computer simulations of …
Date: June 28, 2004
Creator: Max, C. E.; Canalizo, G.; Macintosh, B. A.; Raschke, L.; Whysong, D.; Antonucci, R. et al.
Object Type: Article
System: The UNT Digital Library