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Forbidden line wavelengths and transition probabilities measured using an electron beam ion trap (EBIT)

Description: Several coronal lines posed a long-standing riddle to earth-bound spectroscopists, until - following up on a suggestion by Grotrian (1937) - B. Edlen (1942) confirmed that their wavenumbers indeed corresponded to fine structure intervals in the ground configurations of highly charged ions like Fe X and Fe XI. This in turn caused turmoil in solar physics, because the corona must be much hotter than the underlying chromosphere in order to produce such ions. X-ray and EUV spectra of the sun became available after World War II, by observations from sounding rockets and satellites. These spectra confirmed the presence of the highly charged ions. Laboratory observation of the (electric-dipole) forbidden lines, however, had to wait for the development of low-density plasma discharges like the tokamak fusion experiments, because in regular light sources, collisions would likely quench such long-lived levels. Since then, a fair number of forbidden transitions has been observed in the laboratory, and forbidden lines are being valued for plasma diagnostics. While forbidden transitions in light ions are often found in astrophysical light sources, similar transitions in highly charged heavy ions like Kr will be important for plasma machines like ITER, in which Kr will likely be used for radiative cooling and will therefore also be available for detailed diagnostics.
Date: September 10, 1998
Creator: Beiersdorfer, P.; Gillaspy, J. D.; Serpa, F. G.; Trabert, E. & Utter, S. B.
Partner: UNT Libraries Government Documents Department

Trapping Moles and Utilizing Their Skins with Especial Reference to the Pacific Coast States

Description: "Farmers' boys and others who may wish to trap moles will find in this bulletin information regarding the best kinds of traps, with directions where and how to set them, and how to prepare the skins. Moleskins may be sold to local furriers, or, if these skins are not handled by them, information regarding prices and methods of shipment may be obtained from furs houses that do business by mail.... The methods of trapping moles discussed in this bulletin are especially adapted to the Pacific Coast States, but with modifications will apply to all localities where moles are found." -- p. 2
Date: 1917
Creator: Scheffer, Theodore H.
Partner: UNT Libraries Government Documents Department

SITE CHARACTERIZATION USING JOINT RECONSTRUCTIONS OF DISPARATE DATA TYPES

Description: Potential CO{sub 2} reservoirs are often geologically complex and possible leakage pathways such as those created. Reservoir heterogeneity can affect injectivity, storage capacity, and trapping rate. Similarly, discontinuous caprocks and faults can create risk of CO{sub 2} leakage. The characteristics of potential CO{sub 2} reservoirs need to be well understood to increase confidence in injection project success. Reservoir site characterization will likely involve the collection and integration of multiple geological, geophysical, and geochemical data sets. We have developed a computational tool to more realistically render lithologic models using multiple geological and geophysical techniques. Importantly, the approach formally and quantitatively integrates available data and provides a strict measure of probability and uncertainty in the subsurface. The method will characterize solution uncertainties whether they stem from unknown reservoir properties, measurement error, or poor sensitivity of geophysical techniques.
Date: January 31, 2006
Creator: Ramirez, A.; Friedmann, J.; Dyer, K. & Aines, R.
Partner: UNT Libraries Government Documents Department

Evaluate Status of Pacific Lamprey in the Clearwater River Drainage, Idaho, Annual Report 2002.

Description: In 2002 Idaho Department of Fish and Game continued investigation into the status of Pacific lamprey populations in Idaho's Clearwater River drainage. Trapping, electrofishing, and spawning ground redd surveys were used to determine Pacific lamprey distribution, life history strategies, and habitat requirements in the South Fork Clearwater River, Lochsa River, Selway River, and Middle Fork Clearwater River subbasins. Five-hundred forty-one ammocoetes were captured electroshocking 70 sites in the South Fork Clearwater River, Lochsa River, Selway River, Middle Fork Clearwater River, Clearwater River, and their tributaries in 2002. Habitat utilization surveys in Red River support previous work indicating Pacific lamprey ammocoete densities are greater in lateral scour pool habitats compared to riffles and rapids. Presence-absence survey findings in 2002 augmented 2000 and 2001 indicating Pacific lamprey macrothalmia and ammocoetes are not numerous or widely distributed. Pacific lamprey distribution was confined to the lower reaches of Red River below rkm 8.0, the South Fork Clearwater River, Lochsa River (Ginger Creek to mouth), Selway River (Race Creek to mouth), Middle Fork Clearwater River, and the Clearwater River (downstream to Potlatch River).
Date: October 1, 2003
Creator: Cochnauer, Tim & Claire, Christopher
Partner: UNT Libraries Government Documents Department

High Power Picosecond Laser Pulse Recirculation

Description: We demonstrate a nonlinear crystal-based short pulse recirculation cavity for trapping the second harmonic of an incident high power laser pulse. This scheme aims to increase the efficiency and flux of Compton-scattering based light sources. We demonstrate up to 36x average power enhancement of frequency doubled sub-millijoule picosecond pulses, and 17x average power enhancement of 177 mJ, 10 ps, 10 Hz pulses.
Date: April 12, 2010
Creator: Shverdin, M Y; Jovanovic, I; Semenov, V A; Betts, S M; Brown, C; Gibson, D J et al.
Partner: UNT Libraries Government Documents Department

Fur laws for the season 1929-30.

Description: Discusses the importance of conservation practices to preserve fur resources. Provides a summary of U.S. federal and state laws related to game animals, as well as related laws of Canada, the Dominion of Newfoundland, and Mexico.
Date: 1929
Creator: Earnshaw, Frank L. & Grimes, Frank G.
Partner: UNT Libraries Government Documents Department

Development of a high intensity EBIT for basic and applied science/011

Description: The electron-beam ion trap (EBIT) is a device for producing and studying cold, very highly charged ions of any element, up to a fully ionized U{sup 92+}. These highly charged ions occur in hot plasmas and therefore play important roles in nuclear weapons, controlled fusion, and astrophysical phenomena. The remarkable interaction of these ions with surfaces may lead to technological applications. The highly charged ions can either be studied inside the EBIT itself with measurements of their x-ray emission spectra, or the ions can be extracted from the EBIT in order to study their interaction with solid material. Both types of measurements are being pursued vigorously with the two existing low-intensity EBITs at LLNL and with similar EBITs that have been built at six other laboratories around the world since the EBIT was first developed at LLNL 10 years ago. However, all existing EBITs have approximately the same intensity as the original LLNL EBIT; that is, they all produce about the same number of very-highly-charged ions (roughly 2 x 10{sup 6} per second) and the same number of x-ray photons (roughly 10{sup 7} per second). The goal of the High-Intensity-EBIT project is to increase the x-ray emission per centimeter of length along the electron beam by a factor of 100 and to increase the ion output by a factor of 1000. This dramatic increase in intensity will enable the next generation of basic and applied experimental research in the structure of highly charged ions. For example, the precision of EBIT x-ray measurements of atomic energy levels- which is now limited by count rate-can be improved by an order of magnitude, and new applications in surface science, nanotechnology, and microscopy will be possible with the expected intense ion beams. When the high ion output is combined with the demonstrated low emittance ...
Date: February 5, 1998
Creator: Marrs, R. E.
Partner: UNT Libraries Government Documents Department

Electron beam ion trap bi-annual report 1996/1997

Description: The research of the EBIT (Electron Beam Ion Trap) program in N Division of the Physics and Space Technology Directorate at LLNL continues to contribute significantly to the understanding of physical processes with low energy highly charged ions in atomic physics, plasma physics, and material science. Low-energy highly charged ions (up to U<sup>92+</sup>), provided by the EBIT facilities, provide a unique laboratory opportunity to study high field effects in atomic structures and dynamic interaction processes. The formation, existence, and structure of highly charged ions in astrophysical environments and laboratory plasmas make highly charged ions desirable for diagnosing various plasma conditions. The strong interaction of highly charged ions with matter and the response of solid surfaces make them a sensitive analysis tool and possibly a future capability for materials modifications at the atomic scale (nano technology). These physical applications require a good understanding and careful study of the dynamics of the interactions of the ions with complex systems. The EBIT group hosted an international conference and a workshop on trapped charged particles. The various talks and discussions showed that physics research with trapped charged particles is a very active and attractive area of innovative research, and provides a basis for research efforts in new areas. It also became obvious that the EBIT/RETRAP project has unique capabilities to perform important new experiments with trapped very highly charged ions at rest, which are complementary to and competitive with research at heavy ion storage rings and other trapping facilities planned or in operation in Europe, Japan, and the United States. Atomic structure research at EBIT provides ever better and more experimental complete benchmark data, supplying data needed to improve atomic theories. Research highlights through 1996 and 1997 include hyperfine structure measurements in H-like ions, QED studies, lifetime and polarization measurements on high-Z highly charged ...
Date: January 5, 1999
Creator: Schneider, D.
Partner: UNT Libraries Government Documents Department

Summary of the session on other effects

Description: The theme of this workshop is to discuss the effects of foreign particles on the native beam in a storage ring. This paper summarizes the session on effects not covered in sessions on fast ion instability, electron cloud instability, and cures. The topics discussed are the beam, the foreign particle, how are foreign particles trapped, and how do foreign particles and beam couple.
Date: July 1, 1997
Creator: Chao, A.
Partner: UNT Libraries Government Documents Department

Issues Arising from Plasma-Wall Interactions in Inner-Class Tokamaks

Description: This section reviews physical processes involved in the implantation of energetic hydrogen into plasma facing materials and its subsequent diffusion, release, or immobilization by trapping or precipitation within the material. These topics have also been discussed in previous reviews. The term hydrogen or H is used here generically to refer to protium, deuterium or tritium.
Date: June 23, 1999
Creator: Wampler, William R.
Partner: UNT Libraries Government Documents Department

Penning trap and resistive cooling of protons. Final technical report, May 1993--March 1995

Description: Trapped H{sup {minus}} has been produced from trapped H{sup +}, H{sub 2}{sup +}, and H{sub 3}{sup +} in an ICR trap. The initial positive ions collide with a cesiated trap surface and are recaptured as H{sup {minus}} by fast reversal of the trapping potential.
Date: July 1, 1995
Creator: Kenefick, R.A.
Partner: UNT Libraries Government Documents Department

Economic Value of North American Skunks

Description: "Among fur animals [the skunk] is second in importance in the United States, the muskrat alone exceeding it in total value of fur produced. Skunk are kept and reared easily in captivity, and under intelligent management may become a source of profit, although thus far those who have made money in raising them have sold the animals chiefly for breeding purposes. Further experiment will be required to decide whether they can be made profitable as fur producers in captivity.... This bulletin discusses the habits and economic importance of the skunk, and furnishes ample instructions to those who desire to raise the animals in inclosures." -- p. 2
Date: 1917
Creator: Lantz, David E. (David Ernest)
Partner: UNT Libraries Government Documents Department

Economic Value of North American Skunks

Description: "Among fur animals [the skunk] is second in importance in the United States, the muskrat alone exceeding it in total value of fur produced. Skunk are kept and reared easily in captivity, and under intelligent management may become a source of profit, although thus far those who have made money in raising them have sold the animals chiefly for breeding purposes. Further experiment will be required to decide whether they can be made profitable as fur producers in captivity.... This bulletin discusses the habits and economic importance of the skunk, and furnishes ample instructions to those who desire to raise the animals in inclosures." -- p. 2
Date: 1923
Creator: Lantz, David E. (David Ernest)
Partner: UNT Libraries Government Documents Department

Cottontail Rabbits in Relation to Trees and Farm Crops

Description: This report discusses the habits of cottontail rabbits and means for controlling their populations in order to protect farm crops and trees. In addition to the rabbit's natural enemies and diseases, effective means of control include hunting, trapping, poisoning, and fences.
Date: 1916
Creator: Lantz, David E. (David Ernest)
Partner: UNT Libraries Government Documents Department

Ion trapping in Recycler Ring

Description: Transverse instabilities have been observed in the antiproton beam stored in the Fermilab Recycler Ring, resulting in a sudden increase in the transverse emittances and a small beam loss. The instabilities appear to occur a few hours after a change in the ramping pattern of the Main Injector which shares the same tunnel. The phenomena have been studied by inducing similar instabilities. However, the mechanism is still unknown. A possible explanation is that the ions trapped in the beam reach such an intensity that collective coupled transverse oscillation occurs. However, there is no direct evidence of the trapped ions at this moment.
Date: June 28, 2004
Creator: Ng, K.Y.
Partner: UNT Libraries Government Documents Department

Mechanistic Studies of Improved Foam EOR Processes

Description: The objective of this research is to widen the application of foam to enhanced oil recovery (EOR) by investigating fundamental mechanisms of foams in porous media. This research will lay the groundwork for more applied research on foams for improved sweep efficiency in miscible gas, steam and surfactant-based EOR. Task 1 investigates the pore-scale interactions between foam bubbles and polymer molecules. Task 2 examines the mechanisms of gas trapping, and interaction between gas trapping and foam effectiveness. Task 3 investigates mechanisms of foam generation in porous media.
Date: January 5, 2005
Creator: Rossen, William R.
Partner: UNT Libraries Government Documents Department

Mechanistic Studies of Improved Foam Eor Processes

Description: The objective of this research is to widen the application of foam to enhanced oil recovery (EOR) by investigating fundamental mechanisms of foams in porous media. This research is to lay the groundwork for more-applied research on foams for improved sweep efficiency in miscible gas, steam and surfactant-based EOR. Task 1 investigates the pore-scale interactions between foam bubbles and polymer molecules. Task 2 examines the mechanisms of gas trapping, and interaction between gas trapping and foam effectiveness. Task 3 investigates mechanisms of foam generation in porous media.
Date: March 16, 2005
Creator: Rossen, William R.
Partner: UNT Libraries Government Documents Department