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Experimental evidence of a dynamic Jahn-Teller effect in C-60(+) (open access)

Experimental evidence of a dynamic Jahn-Teller effect in C-60(+)

Detailed analysis of the HOMO bandshape in the photoelectron spectrum of gaseous C60 reveals a dynamic Jahn-Teller effect in the ground state of C60+. The direct observation of three tunneling states asserts a D3d geometry for the isolated cation, originating from a strong vibronic coupling. These results show that the ionic motion of the ions plays an important role in the electron-phonon interaction.
Date: May 20, 2002
Creator: Canton, S.E.; Yencha, A.J.; Kukk, E.; Bozek, J.D.; Lopes, M.C.A.; Snell, G. et al.
Object Type: Article
System: The UNT Digital Library
[Press release: The Black Academy of Arts and Letters Celebrates Black Music Month with the U.S. and Dallas Premiere of "Wild Women Blues" June 4th-9th Starring Linda Hopkins] (open access)

[Press release: The Black Academy of Arts and Letters Celebrates Black Music Month with the U.S. and Dallas Premiere of "Wild Women Blues" June 4th-9th Starring Linda Hopkins]

Press release from the Black Academy of Arts and Letters discussing a blues music performance produced by the Academy to be performed June 4-9, 2002, at the Naomi Bruton Theater.
Date: May 20, 2002
Creator: Black Academy of Arts and Letters
Object Type: Text
System: The UNT Digital Library
Identification of Non-Pertechnetate Species in Hanford Tank Waste, Their Synthesis, Characterization, and Fundamental Chemistry (open access)

Identification of Non-Pertechnetate Species in Hanford Tank Waste, Their Synthesis, Characterization, and Fundamental Chemistry

Technetium, as pertechnetate (TcO4 -), is a mobile species in the environment. This characteristic, along with its long half-life, (99Tc, t1/2 = 213,000 a) makes technetium a major contributor to the long-term hazard associated with low level waste (LLW) disposal. Technetium partitioning from the nuclear waste at DOE sites will be required so that the LLW forms meet DOE performance assessment criteria. Technetium separations assume that technetium exists as TcO4 - in the waste. However, years of thermal, chemical, and radiolytic digestion in the presence of organic material, has transformed much of the TcO4 - into unidentified, stable, reduced, technetium complexes. To successfully partition technetium from tank wastes, it will be necessary to either remove these technetium species with a new process, or reoxidize them to TcO4 - so that conventional pertechnetate separation schemes will be successful.
Date: May 20, 2002
Creator: Schroeder, Norman C.; Olivares, Jose A. & Ashley, Kenneth R.
Object Type: Report
System: The UNT Digital Library
Heavy ion physics at RHIC and in CMS and the participation of the US nuclear physicists in CMS (open access)

Heavy ion physics at RHIC and in CMS and the participation of the US nuclear physicists in CMS

The field of relativistic heavy ion physics entered a new era with the start of the physics program at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory on Long Island, New York. This dedicated facility allows extensive studies of the nuclear matter phase diagram at the highest temperatures so far available in the laboratory. The goal of the program is to conclusively establish the existence of the deconfined state of nuclear matter predicted by QCD, the Quark Gluon Plasma (QGP), and study its properties.
Date: May 20, 2002
Creator: Vogt, Ramona; Wyslouch, Bolek & Yepes, Pablo
Object Type: Article
System: The UNT Digital Library
Earth Systems Questions in Experimental Climate Change Science: Pressing Questions and Necessary Facilities (open access)

Earth Systems Questions in Experimental Climate Change Science: Pressing Questions and Necessary Facilities

Sixty-four scientists from universities, national laboratories, and other research institutions worldwide met to evaluate the feasibility and potential of the Biosphere2 Laboratory (B2L) as an inclusive multi-user scientific facility (i.e., a facility open to researchers from all institutions, according to agreed principles of access) for earth system studies and engineering research, education, and training relevant to the mission of the United States Department of Energy (DOE).
Date: May 20, 2002
Creator: Osmond, B.
Object Type: Article
System: The UNT Digital Library
The distant type Ia supernova rate (open access)

The distant type Ia supernova rate

We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample,which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.
Date: May 20, 2002
Creator: Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R. S.; Aldering, G.; Astier, P. et al.
Object Type: Article
System: The UNT Digital Library
Market leadership by example: Government sector energy efficiency in developing countries (open access)

Market leadership by example: Government sector energy efficiency in developing countries

Government facilities and services are often the largest energy users and major purchasers of energy-using equipment within a country. In developing as well as industrial countries, government ''leadership by example'' can be a powerful force to shift the market toward energy efficiency, complementing other elements of a national energy efficiency strategy. Benefits from more efficient energy management in government facilities and operations include lower government energy bills, reduced greenhouse gas emissions, less demand on electric utility systems, and in many cases reduced dependence on imported oil. Even more significantly, the government sector's buying power and example to others can generate broader demand for energy-efficient products and services, creating entry markets for domestic suppliers and stimulating competition in providing high-efficiency products and services. Despite these benefits, with the exception of a few countries government sector actions have often lagged behind other energy efficiency policies. This is especially true in developing countries and transition economies - even though energy used by public agencies in these countries may represent at least as large a share of total energy use as the public sector in industrial economies. This paper summarizes work in progress to inventory current programs and policies for government sector energy efficiency …
Date: May 20, 2002
Creator: Van Wie McGrory, Laura; Harris, Jeffrey; Breceda, Miguel; Campbell, Stephanie; Sachu, Constantine; della Cava, Mirka et al.
Object Type: Article
System: The UNT Digital Library
Use of projectional phase space data to infer a 4D particle distribution (open access)

Use of projectional phase space data to infer a 4D particle distribution

We consider beams which are described by a 4D transverse distribution f(x,y,x{prime},y{prime}), where x{prime} {triple_bond} p{sub x}/p{sub z} and z is the axial coordinate. A two-slit scanner is commonly employed to measure, over a sequence of shots, a 2D projection of such a beam's phase space, e.g., f(x,x{prime}). Another scanner might yield f(y,y{prime}) or, using crossed slits, f(x,y). A small set of such 2D scans does not uniquely specify f(x,y,x{prime},y{prime}). We have developed ''tomographic'' techniques to synthesize a ''reasonable'' set of particles in a 4D phase space having 2D densities consistent with the experimental data. These techniques are described in a separate document [A. Friedman, et. al., submitted to Phys. Rev. ST-AB, 2002]. Here we briefly summarize one method and describe progress in validating it, using simulations of the High Current Experiment at Lawrence Berkeley National Laboratory.
Date: May 20, 2002
Creator: Friedman, A.; Grote, D. P.; Celata, C. M. & Staples, J. W.
Object Type: Article
System: The UNT Digital Library
A 1.8 Mev K+ injector for the high current beam transport experiment fusion (open access)

A 1.8 Mev K+ injector for the high current beam transport experiment fusion

For the High Current Beam Transport Experiment (HCX) at LBNL, an injector is required to deliver up to 1.8 MV of 0.6 A K{sup +} beam with an emittance of {approx}1 p-mm-mrad. We have successfully operated a 10-cm diameter surface ionization source together with an electrostatic quadrupole (ESQ) accelerator to meet these requirements. The pulse length is {approx}4 {micro}s, firing at once every 10-15 seconds. By optimizing the extraction diode and the ESQ voltages, we have obtained an output beam with good current density uniformity, except for a small increase near the beam edge. Characterization of the beam emerging from the injector included measurements of the intensity profile, beam imaging, and transverse phase space. These data along with comparison to computer simulations provide the knowledge base for designing and understanding future HCX experiments.
Date: May 20, 2002
Creator: Kwan, J. W.; Bieniosek, F. M.; Henestroza, E.; Prost, L. & Seidl, P.
Object Type: Article
System: The UNT Digital Library
RAD/COMM ''Cricket'' Test Report (open access)

RAD/COMM ''Cricket'' Test Report

A series of tests were performed at Oak Ridge National Laboratory (ORNL) to evaluate and characterize the radiological response of a ''Cricket'' radiation detection system. The ''Cricket'' is manufactured by RAD/COMM Systems Corp., which is located in Ontario, Canada. The system is designed to detect radioactive material that may be contained in scrap metal. The Cricket's detection unit is mounted to the base of a grappler and monitors material, while the grappler's tines hold the material. It can also be used to scan material in an attempt to isolate radioactive material if an alarm occurs. Testing was performed at the Environmental Effects Laboratory located at ORNL and operated by the Engineering Science and Technology Division. Tests performed included the following: (1) Background stability, (2) Energy response using {sup 241}Am, {sup 137}Cs, and {sup 60}Co, (3) Surface uniformity, (4) Angular dependence, (5) Alarm actuation, (6) Alarm threshold vs. background, (7) Shielding, (8) Response to {sup 235}U, (9) Response to neutrons using unmoderated {sup 252}Cf, and (10) Response to transient radiation. This report presents a summary of the test results. Background measurements were obtained prior to the performance of each individual test.
Date: May 20, 2002
Creator: Chiaro, P. J.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 175, Ed. 1 Monday, May 20, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 175, Ed. 1 Monday, May 20, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: May 20, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History

Boiling Springs State Park

Photograph of a scene at Shaul Lake, in the Boiling Springs State Park.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Boiling Springs State Park

Photograph of a scene during the Northwest Oklahoma Bluegrass Jam, at Boiling Springs State Park.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Little Sahara State Park

Photograph of a scene in Little Sahara State Park.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Windmill Museum

Photograph of a scene at the Shattuck Windmill Museum.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Cimarron River

Photograph of Red Bluffs along the Cimarron River.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Windmill Museum

Photograph of a scene at the Shattuck Windmill Museum.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Cimarron River

Photograph of Red Bluffs along the Cimarron River.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Cimarron River

Photograph of Red Bluffs along the Cimarron River.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Boiling Springs State Park

Photograph of a scene at Shaul Lake, in the Boiling Springs State Park.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Windmill Museum

Photograph of a scene at the Shattuck Windmill Museum.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Boiling Springs State Park

Photograph of ducks, at Shaul Lake, in the Boiling Springs State Park.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Little Sahara State Park

Photograph of a scene in Little Sahara State Park.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History

Windmill Museum

Photograph of a scene at the Shattuck Windmill Museum.
Date: May 20, 2002
Creator: Argo, Jim
Object Type: Photograph
System: The Gateway to Oklahoma History