Partner
UNT Libraries Government Documents Department
290
UNT Libraries
191
UNT Libraries Special Collections
115
Oklahoma Historical Society
49
San Antonio Public Library
11
Sterling Municipal Library
11
Carl Albert Congressional Research and Studies Center
7
National Museum of the Pacific War/Admiral Nimitz Foundation
6
UNT Music Library
6
Patrick Heath Public Library
5
45 More
Collection
Photographing Texas
152
Office of Scientific & Technical Information Technical Reports
146
Texas Digital Newspaper Program
131
Congressional Research Service Reports
106
José L. Castillo Photograph Collection
61
Oklahoma Digital Newspaper Program
57
Tocker Foundation Grant
48
The Greensheet
32
Government Accountability Office Reports
30
Multicultural Center Records
25
81 More
Degree Department
States
Year
Month
Day
Results:
1 - 24 of
771
next
The H II Region of a Primordial Star
The concordance model of cosmology and structure formation predicts the formation of isolated very massive stars at high redshifts in dark matter dominated halos of 10{sup 5} to 10{sup 6} Msun. These stars photo-ionize their host primordial molecular clouds, expelling all the baryons from their halos. When the stars die, a relic H II region is formed within which large amounts of molecular hydrogen form which will allow the gas to cool efficiently when gravity assembles it into larger dark matter halos. The filaments surrounding the first star hosting halo are largely shielded and provide the pathway for gas to stream into the halo when the star has died. We present the first fully three dimensional cosmological radiation hydrodynamical simulations that follow all these effects. A novel adaptive ray casting technique incorporates the time dependent radiative transfer around point sources. This approach is fast enough so that radiation transport, kinetic rate equations, and hydrodynamics are solved self-consistently. It retains the time derivative of the transfer equation and is explicitly photon conserving. This method is integrated with the cosmological adaptive mesh refinement code enzo, and runs on distributed and shared memory parallel architectures. Where applicable the three dimensional calculation not only …
Date:
June 7, 2006
Creator:
Abel, Tom; Wise, John H.; /KIPAC, Menlo Park; Bryan, Greg L. & /Columbia U., Astron. Astrophys.
Object Type:
Report
System:
The UNT Digital Library
Temperature sensitivity of Cu K(alpha) imaging efficiency using a spherical Bragg reflecting crystal
The Vulcan laser facility at the Rutherford Appleton Laboratory was used to study the interaction of a 75 J 10 ps, high intensity laser beam with low-mass solid, Cu targets. Two instruments were fielded as diagnostics of the Cu K-shell emission from the targets: A single photon counting CCD spectrometer provided the absolute K{sub {alpha}} yield and a spherically bent Bragg crystal recorded 2D monochromatic images with a spatial resolution of 10 {micro}m. Due to the shifting and broadening of the K{sub {alpha}} spectral lines with increasing temperature, there is a temperature dependence of the crystal collection efficiency. This provides a temperature diagnostic when cross calibrated against a single hit CCD spectrometer, and it affects measurements of the spatial pattern of electron transport. The experimental data showing changing collection efficiency are presented. The results are discussed in light of modeling of the temperature-dependent spectrum of Cu K-shell emission.
Date:
August 7, 2006
Creator:
Akli, K. U.; Key, M. H.; Chung, H. K.; Hansen, S. B.; Freeman, R. R.; Chen, M. H. et al.
Object Type:
Article
System:
The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 36, Ed. 1 Thursday, September 7, 2006
Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date:
September 7, 2006
Creator:
Alexander, Nancy
Object Type:
Newspaper
System:
The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 21, No. 49, Ed. 1 Thursday, December 7, 2006
Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date:
December 7, 2006
Creator:
Alexander, Nancy
Object Type:
Newspaper
System:
The Portal to Texas History
Evolution of Ni3X Precipitation Kinetics, Morphology and Spatial Correlations in Binary Ni-X Alloys Aged Under Externally Applied Stress
Coarsening of Ni3Al, Ni3Ga, Ni3Ge and Ni3Si precipitates in aged binary single-crystal Ni-Al, Ni-Ga, Ni-Ge and Ni-Si alloys under applied compressive stress was measured experimentally over the temperature range 600 to 700 ÃÂÃÂâÃÂÃÂÃÂÃÂÃÂðC. Experiments were also performed on binary Ni-Al single crystals deformed in tension at 640 ÃÂÃÂâÃÂÃÂÃÂÃÂÃÂðC. The orientation of the crystals was [100] in all the experiments. Compared to the kinetics of coarsening in unstressed alloys, coarsening was slightly slower in specimens aged under compression and slightly faster in specimens aged in tension. The effect of applied stress on morphology and spatial correlation was also measured and found to be small. Ni3Al precipitates of a given size generally tended to become more non-equiaxed and their interfaces more planar, with increasing compressive stress. Ni3Ge precipitates behaved differently, becoming more spherical in specimens aged under compression. The effect of applied stress on kinetics is attributed to the influence of elastic deformation on diffusion. A model was developed that predicts slightly slower diffusion under compression and slightly faster diffusion in tension. The elastic constants of single crystals of Ni-Al, Ni-Si, Ni-Ga and Ni-Ge solid solutions were measured from room temperature to about 1100 K using resonant ultrasound spectroscopy.
Date:
February 7, 2006
Creator:
Ardell, Alan J.
Object Type:
Report
System:
The UNT Digital Library
Inclusive Lambda_c Production in e+e- Annihilations at sqrt{s}=10.54 GeV and in Upsilon(4S) Decays
We present measurements of the total production rates and momentum distributions of the charmed baryon {Lambda}{sub c}{sup +} in e{sup +}e{sup -} {yields} hadrons at a center-of-mass energy of 10.54 GeV and in {Upsilon}(4S) decays. In hadronic events at 10.54 GeV, charmed hadrons are almost exclusively leading particles in e{sup +}e{sup -} {yields} c{bar c} events, allowing direct studies of c-quark fragmentation. We measure a momentum distribution for {Lambda}{sub c}{sup +} baryons that differs significantly from those measured previously for charmed mesons. Comparing with a number of models, we find none that can describe the distribution completely. We measure an average scaled momentum of (x{sub p}) = 0.574 {+-} 0.009 and a total rate of N{sub {Lambda}{sub c}}{sup q{bar q}} = 0.057 {+-} 0.002(exp.) {+-} 0.015(BF) {Lambda}{sub c}{sup +} per hadronic event, where the experimental error is much smaller than that due to the branching fraction into the reconstructed decay mode, pK{sup -} {pi}{sup +}. In {Upsilon}(4S) decays we measure a total rate of N{sub {Lambda}{sub c}}{sup {Upsilon}} = 0.091 {+-} 0.006(exp.) {+-} 0.024(BF) per {Upsilon}(4S) decay, and find a much softer momentum distribution than expected from B decays into a {Lambda}{sub c}{sup +} plus an antinucleon and one to …
Date:
September 7, 2006
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Measurements of Branching Fractions, Rate Asymmetries, and Angular Distributions in the Rare Decays B -> Kl+l- and B -> K*l+ l-
We present measurements of the flavor-changing neutral current decays B {yields} K{ell}{sup +}{ell}{sup -} and B {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either an e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -} pair. The data sample comprises 229 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. Flavor-changing neutral current decays are highly suppressed in the Standard Model and their predicted properties could be significantly modified by new physics at the electroweak scale. We measure the branching fractions {Beta}(B {yields} K{ell}{sup +}{ell}{sup -}) = (0.34 {+-} 0.07 {+-} 0.02) x 10{sup -6}, {Beta}(B {yields} K*{ell}{sup +}{ell}{sup -}) = (0.78{sub -0.17}{sup +0.19} {+-} 0.11) x 10{sup -6}, the direct CP asymmetries of these decays, and the relative abundances of decays to electrons and muons. For two regions in {ell}{sup +}{ell}{sup -} mass, above and below m{sub J/{psi}}, we measure partial branching fractions and the forward-backward angular asymmetry of the lepton pair. In these same regions we also measure the K* longitudinal polarization in B {yields} K*{ell}{sup +}{ell}{sup -} decays. Upper limits are obtained for the lepton flavor-violating decays B {yields} Ke{mu} and B {yields} K*e{mu}. All measurements …
Date:
April 7, 2006
Creator:
Aubert, B.
Object Type:
Report
System:
The UNT Digital Library
Search for the Charmed Pentaquark Candidate Theta_c(3100)^0 in e^+e^- Annihilations at \sqrt{s}=10.58 GeV
We search for the charmed pentaquark candidate reported by the H1 collaboration, the {Theta}{sub c}(3100){sup o}, in e{sup +}e{sup -} interactions at a center-of-mass (c.m.) energy of 10.58 GeV, using 124 fb{sup -1} of data recorded with the BABAR detector at the PEP-II e{sup +}e{sup -} facility at SLAC. We find no evidence for such a state in the same pD*{sup -} decay mode reported by H1, and we set limits on its production cross section times branching fraction into pD*{sup -} as a function of c.m. momentum. The corresponding limit on its total rate per e{sup +}e{sup -} {yields} q{bar q} event, times branching fraction, is about three orders of magnitude lower than rates measured for the charmed {Lambda}{sub c} and {Sigma}{sub c} baryons in such events.
Date:
April 7, 2006
Creator:
Aubert, B.
Object Type:
Report
System:
The UNT Digital Library
Study of the Exclusive Initial State RadiationProduction of the D \bar D System
A study of exclusive production of the D{bar D} system through initial-state radiation is performed in a search for charmonium states, where D = D{sup 0} or D{sup +}. The D{sup 0} mesons are reconstructed in the D{sup 0} {yields} K{sup -}{pi}{sup +}, D{sup 0} {yields} K{sup -}{pi}{sup +}{pi}{sup 0}, and D{sup 0} {yields} K{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -} decay modes. The D{sup +} is reconstructed through the D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +} decay mode. The analysis makes use of an integrated luminosity of 288.5 fb{sup -1} collected by the BABAR experiment. The D{bar D} mass spectrum shows a clear {psi}(3770) signal. Further structures appear in the 3.9 and 4.1 GeV/c{sup 2} regions. No evidence is found for Y(4260) decays to D{bar D}, implying an upper limit {Beta}(Y(4260) {yields} D{bar D})/{Beta}(Y(4260) {yields} J/{psi}{pi}{sup +}{pi}{sup -}) < 7.6 (95% confidence level).
Date:
September 7, 2006
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
[Immigration Debates panel members]
Photograph of four panel members sitting at the Immigration Debates hosted by the UPC. Three men and a young woman (2nd left) can be seen sitting at a long table, facing the camera. Debate attendees are visible in the foreground of the photograph with their backs turned to the camera.
Date:
April 7, 2006
Creator:
Baugh, Brian
Object Type:
Photograph
System:
The UNT Digital Library
FEMA Reorganization Legislation in the 109th Congress
None
Date:
July 7, 2006
Creator:
Bea, Keith & Hogue, Henry B.
Object Type:
Report
System:
The UNT Digital Library
The Grandview Tribune (Grandview, Tex.), Vol. 111, No. 31, Ed. 1 Friday, April 7, 2006
Weekly newspaper from Grandview, Texas that includes local, state, and national news along with advertising.
Date:
April 7, 2006
Creator:
Beck-Adams, Candie
Object Type:
Newspaper
System:
The Portal to Texas History
Animal Identification and Meat Traceability
U.S. animal agriculture is seeking to improve its ability to trace the movement of livestock from their birthplace to slaughter. The livestock and meat industries are working with the U.S. government to develop a national animal identification (ID) plan for livestock disease tracking purposes. This report focuses on animal ID and, to a lesser extent, on meat traceability.
Date:
March 7, 2006
Creator:
Becker, Geoffrey S.
Object Type:
Report
System:
The UNT Digital Library
Why Pi And Mrad
Today it is generally accepted in the ion source and accelerator communities to communicate emittance data with units of {pi} mm mrad or {pi} cm mrad. The emittance of a beam with 2 cm diameter or width and an opening angle of 200 mrad then is written as E=100 {pi} cm mrad. This example shows that {pi} has not been involved when calculating the half-axis product which is the numerical definition for the emittance. Why should we add {pi} to the dimensions? We will explain that this convention is not at all a logical one and is confusing to all those who are entering the field as freshmen or just do not want to become experts by adjusting to strange rules. We therefore propose to skip the ''{pi}'' in the dimension and to add characters as sub- or superscripts to the variable E, which describe the specific kind of emittance formulation used, e.g., E{sub r,r'}, E{sub x,x'}, E{sub rms}, E{sub 4*rms}, E{sub norm}, E{sub area}, and E{sub ellipse}. In a real case, such an emittance naming could appear as E{sub x,x',4rms}{sup norm}. Additionally--to be consistent with cleaning up--the dimension of emittances should be given in centimeters or meters, because rad …
Date:
July 7, 2006
Creator:
Becker, R.; U., /Frankfurt & Herrmannsfeldt, W.B.
Object Type:
Article
System:
The UNT Digital Library
Gasoline Prices: New Legislation and Proposals
The high price of gasoline was an important consideration during the debate on the Energy Policy Act of 2005, H.R. 6. As prices continued to surge, the continuing crisis renewed attention on some issues that were dropped or compromised in the debate over P.L. 109-58, as well as to a number of initiatives to reduce the impact of high prices on consumers. A large number of factors have combined to put pressure on gasoline prices, including increased world demand for crude oil and limited U.S. refinery capacity to supply gasoline to a growing national economy. Among the issues receiving new attention were vehicle fuel economy standards, leasing on the Outer Continental Shelf, and refinery "revitalization" provisions.
Date:
July 7, 2006
Creator:
Behrens, Carl E. & Glover, Carol
Object Type:
Report
System:
The UNT Digital Library
Gasoline Prices: New Legislation and Proposals
The continuing crisis of high gasoline prices has led to a broad spectrum of proposed new legislation. Despite passage of the major Energy Policy Act of 2005 (P.L. 109-58) in 2005, many Members are exploring a variety of measures to increase supply and reduce demand in the short term, and to reduce the impact of high prices on consumers. Some are also proposing to revisit longer term policies, some of which were passed up in the process of reaching agreement on P.L. 109-58. This report reviews the major legislative initiatives to deal with the gasoline price issue. To put these proposals in perspective, it first describes some of the factors that have led to the high prices of both crude oil and gasoline.
Date:
July 7, 2006
Creator:
Behrens, Carl E. & Glover, Carol
Object Type:
Report
System:
The UNT Digital Library
Fayette County Courthouse, cornerstone detail
Photograph of a cornerstone at the Fayette County Courthouse in La Grange. The text on the cornerstone reads "Fayette County, April 9th 1891, J.R. Gordon, Architect, Martin Burns & Johnsen, Builders." There is also a masonic symbol, "La Fayette Lodge, No. 34, A.F. & A.M., A. L. 5891."
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History
Fayette County Courthouse, detail of stonework.
Photograph of the stonework at the Fayette County Courthouse in La Grange. It includes Belton white limestone, blue sandstone quarried near Muldoon, and Red Pecos sandstone.
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History
Fayette County Courthouse, detail of windows
Photograph of the windows at the Fayette County Courthouse in La Grange. The glass is set into red wood, and there are wooden shutters inside. There are carved stone squares between each level of windows.
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History
Fayette County Courthouse grounds, La Grange
Photograph of a meridian stone on the grounds of the Fayette County Courthouse in La Grange. It reads "Fayette Co. Meridian, erected A.D. 1878"
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History
Fayette County Courthouse grounds, La Grange, base of light post
Photograph of the base of a lamp post at the Fayette County Courthouse in La Grange. It reads: "Lost Pine Tree. "I dedicate this tree to the people of Fayette County, their historic past, ambitious present, and glorious future." Lady Bird Johnson, July 7, 1867. Through the efforts of congressman J.J. "Jake" Pickle, 10th Congressional District and others, the above dedication was made possible."
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History
Fayette County Courthouse grounds, La Grange, base of light post
Photograph of the base of a lamp post on the ground of the Fayette County Courthouse in La Grange. It reads: "County Heritage: Fayette County was settled by members of the Old Three-Hundred, and created from Bastrop and Colorado Counties. It was named for the Marquis de LaFayette, and the county seat for his chateau in France. With dedication and perseverance, our forefathers gave the county its rich heritage and a prominent place in history. The Mier Expedition and Dawson's Company contributed to its early historical background, and the remains of these courageous men now lie on Monument Hill. The county has contributed many of its young men to keep the peace of this great nation, and this edifice will stand as a monument to their loyalty, courage, and sacrifice."
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History
Fayette County Courthouse grounds, La Grange, base of light post
Photograph of the base of a lamp post at the Fayette County Courthouse in La Grange. It reads: "County Commissioners Court, 1967, County Judge, Ike J. Petras; Commissioners: Gunther Behrens, Precinct 1; Clinton P. Krause, Precinct 2; Eddie Zouzalik, Precinct 3; Henry Dittrich, Precinct 4 ".
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History
Fayette County Courthouse grounds, La Grange, base of light post
Photograph of the base of a lamp post at the Fayette County Courthouse in La Grange. It reads: "County Officials, 1838. Chief Justice, Andrew Rabb; County Clerk, David S. Kornegay; Sheriff, John Breeding; Tax Assessor, Michael R. Goheen; County Surveyor, Thomas Green; Coroner, Socrates Darling; District Clerk, Jerome B. Alexander".
Date:
October 7, 2006
Creator:
Belden, Dreanna L.
Object Type:
Photograph
System:
The Portal to Texas History