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General Constraints on Cross Sections Deduced from Surrogate Reactions (open access)

General Constraints on Cross Sections Deduced from Surrogate Reactions

Cross sections that cannot be measured in the laboratory, e.g. because the target lifetime is too short, can be inferred indirectly from a different reaction forming the same compound system, but with a more accessible beam/target combination (the ''surrogate-reaction'' technique). The reactions share the same compound system and a common decay mechanism, but they involve different formation processes. Therefore, an implicit constraint is imposed on the inferred cross section deduced from the measured surrogate-reaction data, through the common decay mechanism. In this paper, the mathematical consequences of this implicit constraint are investigated. General formulas are derived from upper and lower bounds on the inferred cross section, estimated from surrogate data in a procedure which does not require any modeling of the common decay process. As an example, the formulas developed here are applied to the case of the {sup 235}U(n,f) cross section, deduced from {sup 234}U(t,pf) surrogate data. The calculated bounds are not very tight in this particular case. However, by introducing a few qualitative assumptions about the physics of the fission process, meaningful bounds on the deduced cross section are obtained. Upper and lower limits for the cross-section ratio of the (n,f) reaction on the {sup 235}U isomer at …
Date: August 14, 2003
Creator: Younes, W.
Object Type: Report
System: The UNT Digital Library
The Albany News (Albany, Tex.), Vol. 128, No. 11, Ed. 1 Thursday, August 14, 2003 (open access)

The Albany News (Albany, Tex.), Vol. 128, No. 11, Ed. 1 Thursday, August 14, 2003

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: August 14, 2003
Creator: Lucas, Melinda L.
Object Type: Newspaper
System: The Portal to Texas History
Forest Fire/Wildfire Protection (open access)

Forest Fire/Wildfire Protection

This report provides historical background on wildfires, and describes concerns about the wildland-urban interface and about forest and rangeland health. It discusses fuel management, fire control, and fire effects and also examines federal, state, and landowner roles and responsibilities in protecting lands and resources from wildfires. The report concludes by discussing current issues for federal wildfire management.
Date: August 14, 2003
Creator: Gorte, Ross W.
Object Type: Report
System: The UNT Digital Library
Texas Jewish Post (Fort Worth, Tex.), Vol. 57, No. 33, Ed. 1 Thursday, August 14, 2003 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 57, No. 33, Ed. 1 Thursday, August 14, 2003

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state, and national news along with extensive advertising.
Date: August 14, 2003
Creator: Wisch, Rene & Wisch-Ray, Sharon
Object Type: Newspaper
System: The Portal to Texas History
Archer County News (Archer City, Tex.), No. 33, Ed. 1 Thursday, August 14, 2003 (open access)

Archer County News (Archer City, Tex.), No. 33, Ed. 1 Thursday, August 14, 2003

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date: August 14, 2003
Creator: Lewis, Shelley
Object Type: Newspaper
System: The Portal to Texas History
Polk County Enterprise (Livingston, Tex.), Vol. 121, No. 65, Ed. 1 Thursday, August 14, 2003 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 121, No. 65, Ed. 1 Thursday, August 14, 2003

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: August 14, 2003
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Hondo Anvil Herald (Hondo, Tex.), Vol. 117, No. 33, Ed. 1 Thursday, August 14, 2003 (open access)

Hondo Anvil Herald (Hondo, Tex.), Vol. 117, No. 33, Ed. 1 Thursday, August 14, 2003

Weekly newspaper from Hondo, Texas that includes local, state, and national news along with extensive advertising.
Date: August 14, 2003
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Historical background: Why is it important to improve automated particle selection methods? (open access)

Historical background: Why is it important to improve automated particle selection methods?

A current trend in single-particle electron microscopy is to compute three-dimensional reconstructions with ever-increasing numbers of particles in the data sets. Since manual--or even semi-automated--selection of particles represents a major bottleneck when the data set exceeds several thousand particles, there is growing interest in developing automatic methods for selecting images of individual particles. Except in special cases, however, it has proven difficult to achieve the degree of efficiency and reliability that would make fully automated particle selection a useful tool. The simplest methods such as cross correlation (i.e., matched filtering) do not perform well enough to be used for fully automated particle selection. Geometric properties (area, perimeter-to-area ratio, etc.) and the integrated ''mass'' of candidate particles are additional factors that could improve automated particle selection if suitable methods of contouring particles could be developed. Another suggestion is that data be always collected as pairs of images, the first taken at low defocus (to capture information at the highest possible resolution) and the second at very high defocus (to improve the visibility of the particle). Finally, it is emphasized that well-annotated, open-access data sets need to be established in order to encourage the further development and validation of methods for automated …
Date: August 14, 2003
Creator: Glaeser, Robert M.
Object Type: Article
System: The UNT Digital Library
Radiation load to the SNAP CCD (open access)

Radiation load to the SNAP CCD

Results of an express Monte Carlo analysis with the MARS14 code of radiation load to the CCD optical detectors in the Supernova Acceleration Project (SNAP) mission presented for realistic radiation environment over the satellite orbit.
Date: August 14, 2003
Creator: N. V. Mokhov, I. L. Rakhno and S. I. Striganov
Object Type: Report
System: The UNT Digital Library
Booster's coupled bunch damper upgrade (open access)

Booster's coupled bunch damper upgrade

A new narrowband active damping system for longitudinal coupled bunch (CB) modes in the Fermilab Booster has recently been installed and tested. In the past, the Booster active damper system consisted of four independent front-ends. The summed output was distributed to the 18, h=84 RF accelerating cavities via the RF fan-out system. There were several problems using the normal fan-out system to deliver the longitudinal feedback RF. The high power RF amplifiers normally operate from 37 MHz to 53 MHz whereas the dampers operate around 83MHz. Daily variations in the tuning of the RF stations created tuning problems for the longitudinal damper system. The solution was to build a dedicated narrowband, Q {approx} 10, 83MHz cavity powered with a new 3.5kW solid-state amplifier. The cavity was installed in June 2002 and testing of the amplifier and damper front-end began in August 2002. A significant improvement has been made in both operational stability and high intensity beam damping. At present there are five CB modes being damped and a sixth mode module is being built. The new damper hardware is described and data showing the suppression of the coupled-bunch motion at high intensity is presented.
Date: August 14, 2003
Creator: Wildman, William A. Pellico and D. W.
Object Type: Article
System: The UNT Digital Library
Regulation of the genes involved in nitrification. (open access)

Regulation of the genes involved in nitrification.

OAK-B135 This project focuses on the characterization of the regulation of the genes involved in nitrification in the bacterium Nitrosomonas europaea. The key genes in the nitrification pathway, amo and hao, are present in multiple copies in the genome. The promoters for these genes were identified and characterized. It was shown that there were some differences in the transcriptional regulation of the copies of these genes.
Date: August 14, 2003
Creator: Arp, D.J. & Sayavedra-Soto, L.A.
Object Type: Report
System: The UNT Digital Library
Geothermal Resource Analysis and Structure of Basin and Range Systems, Especially Dixie Valley Geothermal Field, Nevada (open access)

Geothermal Resource Analysis and Structure of Basin and Range Systems, Especially Dixie Valley Geothermal Field, Nevada

Publish new thermal and drill data from the Dizie Valley Geothermal Field that affect evaluation of Basin and Range Geothermal Resources in a very major and positive way. Completed new geophysical surveys of Dizie Valley including gravity and aeromagnetics and integrated the geophysical, seismic, geological and drilling data at Dizie Valley into local and regional geologic models. Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dizie Valley data that help to understand the nature of large scale constraints on the location and characteristics of the geothermal systems. Documented a relation between natural heat loss for geothermal and electrical power production potential and determined heat flow for 27 different geothermal systems. Prepared data set for generation of a new geothermal map of North American including industry data totaling over 25,000 points in the US alone.
Date: August 14, 2003
Creator: Blackwell, David; Wisian, Kenneth; Richards, Maria; Leidig, Mark; Smith, Richard & McKenna, Jason
Object Type: Report
System: The UNT Digital Library
Stamford American (Stamford, Tex.), Vol. 83, No. 20, Ed. 1 Thursday, August 14, 2003 (open access)

Stamford American (Stamford, Tex.), Vol. 83, No. 20, Ed. 1 Thursday, August 14, 2003

Weekly newspaper from Stamford, Texas that includes local, state, and national news along with advertising.
Date: August 14, 2003
Creator: Powell, Cheyenne
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 261, Ed. 1 Thursday, August 14, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 261, Ed. 1 Thursday, August 14, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 14, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
The Canadian Record (Canadian, Tex.), Vol. 113, No. 33, Ed. 1 Thursday, August 14, 2003 (open access)

The Canadian Record (Canadian, Tex.), Vol. 113, No. 33, Ed. 1 Thursday, August 14, 2003

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: August 14, 2003
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
Rio Grande Herald (Rio Grande City, Tex.), Vol. 90, No. 32, Ed. 1 Thursday, August 14, 2003 (open access)

Rio Grande Herald (Rio Grande City, Tex.), Vol. 90, No. 32, Ed. 1 Thursday, August 14, 2003

Weekly newspaper from Rio Grande City, Texas that includes local, state and national news along with extensive advertising.
Date: August 14, 2003
Creator: Roberts, Kenneth
Object Type: Newspaper
System: The Portal to Texas History
The Distribution of Househol d Wealth in the United States (open access)

The Distribution of Househol d Wealth in the United States

This report gives an overview of the distribution of household wealth in the United States. The contents include recent trends in household wealth, changes in composition, family stock holdings and explaining the distribution of Wealth.
Date: August 14, 2003
Creator: Cashell, Brian W.
Object Type: Report
System: The UNT Digital Library
The August 14, 2003 meeting was a tour of the Collin County Detention Facility (open access)

The August 14, 2003 meeting was a tour of the Collin County Detention Facility

Document about the McKinney Chapter of the Texas Society, Sons of the American Revolution.
Date: August 14, 2003
Creator: Texas Society, Sons of the American Revolution, McKinney Chapter 63
Object Type: Text
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 105, No. 129, Ed. 1 Thursday, August 14, 2003 (open access)

Altus Times (Altus, Okla.), Vol. 105, No. 129, Ed. 1 Thursday, August 14, 2003

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 14, 2003
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Timpson & Tenaha News (Timpson, Tex.), Vol. 18, No. 32, Ed. 1 Thursday, August 14, 2003 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 18, No. 32, Ed. 1 Thursday, August 14, 2003

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: August 14, 2003
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Thorium Nitrate Stockpile Drum Characterization Report (open access)

Thorium Nitrate Stockpile Drum Characterization Report

None
Date: August 14, 2003
Creator: Hylton, TD
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Thursday, August 14, 2003 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Thursday, August 14, 2003

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: August 14, 2003
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 88, No. 286, Ed. 1 Thursday, August 14, 2003 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 88, No. 286, Ed. 1 Thursday, August 14, 2003

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: August 14, 2003
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Search for rare charm meson decays at FNAL E791 (open access)

Search for rare charm meson decays at FNAL E791

We report the results of a blind search for flavor-changing neutral current (FCNC), lepton-flavor violating, and lepton-number violating decays of D{sup +}, D{sub s}{sup +}, and D{sup 0} mesons (and their antiparticles) into 2-, 3-, and 4-body states including a lepton pair. Such decays may involve Flavor-Changing Neutral Currents, Leptoquarks, Horizontal Gauge Bosons, or Majorana Neutrinos. No evidence for any of these decays is found. Therefore, we present 90% confidence level branching-fraction upper limits, typically at the 10{sup -4} level. A total of 51 decay channels have been examined; 26 have not been previously reported and 18 are significant improvements over previous results.
Date: August 14, 2003
Creator: Summers, D. J.
Object Type: Article
System: The UNT Digital Library