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Nuclear level densities and radiative strength functions (RSF) in {sup 56}Fe and {sup 57}Fe were measured using the {sup 57}Fe({sup 3}He,{alpha}{gamma}) and {sup 57}Fe({sup 3}He, {sup 3}He{prime}{gamma}) reactions, respectively, at Oslo Cyclotron Laboratory. A low-energy enhancement in the RSF below 4 MeV energy was observed. This finding cannot be explained by common theoretical models. In a second experiment, two-step cascade intensities with soft primary transitions from the {sup 56}Fe(n,2{gamma}) reaction were measured. The agreement between the two experiments confirms the low-energy enhancement in the RSF. In a third experiment, the neutron evaporation spectrum from the {sup 55}Mn(dn,N){sup 56}Fe reaction was measured at 7-MeV deuteron energy at John Edwards Accelerator Laboratory at Ohio University. Comparison of the level density of {sup 56}Fe obtained from the first and third experiments gives an overall good agreement. Furthermore, observed enhancement for soft {gamma} rays is supported by the last experiment.

The BaBar drift chamber (DCH) is used to measure the properties of charged particles created from e{sup +}e{sup -} collisions in the PEP-II asymmetric-energy storage rings by making precise measurements of position, momentum and ionization energy loss (dE/dx). In October of 2005, the PEP-II storage rings operated with a luminosity of 10 x 10{sup 33} cm{sup -2}s{sup -1}; the goal for 2007 is a luminosity of 20 x 10{sup 33} cm{sup -2}s{sup -1}, which will increase the readout dead time, causing uncertainty in drift chamber measurements to become more significant in physics results. The research described in this paper aims to reduce position and dE/dx uncertainties by improving our understanding of the BaBar drift chamber performance. A simulation program--called GARFIELD--is used to model the behavior of the drift chamber with adjustable parameters such as gas mixture, wire diameter, voltage, and magnetic field. By exploring the simulation options offered in GARFIELD, we successfully produced a simulation model of the BaBar drift chamber. We compared the time-to-distance calibration from BaBar to that calculated by GARFIELD to validate our model as well as check for discrepancies between the simulated and calibrated time-to-distance functions, and found that for a 0{sup o} entrance angle there …

The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA) is shipping, for disposition purposes, bulk quantities of fissile materials, primarily highly enriched uranium (HEU). The U.S. Department of Transportation (DOT) specification 6M container has been the workhorse for NNSA and many other shippers of radioactive material since the 1980s. However, the 6M does not conform to the packaging requirements in the Code of Federal Regulations (10 CFR 71) and, for that reason, is being phased out for use in the DOE secure transportation system by the end of 2006. BWXT Y-12 developed and licensed the ES-3100 container to replace the DOT 6M. The ES-3100 was certified by the Nuclear Regulatory Commission (NRC) in April 2006. The process of deploying the new package began in June 2005 and is planned to be completed in July 2006. The package will be fully operational and completely replace the DOT 6M at the Y-12 National Security Complex (Y-12) by October 2006. This paper reviews the deployment process and the mock loading station that was installed at National Transportation Research Center (NTRC) of Oak Ridge National Laboratory. Specialized equipment, tools, and instrumentation that support the handling and loading operations of the ES-3100 are …

High-redshift blazars are promising candidates for detection by the Gamma-ray Large Area Space Telescope (GLAST). GLAST, expected to be launched in the Fall of 2007, is a high-energy gamma-ray observatory designed for making observations of celestial gamma-ray sources in the energy band extending from 10 MeV to more than 200 GeV. It is estimated that GLAST will find several thousand blazars. The motivations for measuring the gamma-ray emission from distant blazars include the study of the high-energy emission processes occurring in these sources and an indirect measurement of the extragalactic background light. In anticipation of the launch of GLAST we have compiled a catalog of candidate high-redshift blazars. The criteria for sources chosen for the catalog were: high radio emission, high redshift, and a flat radio spectrum. A preliminary list of 307 radio sources brighter than 70mJy with a redshift z {ge} 2.5 was acquired using data from the NASA Extragalactic Database. Flux measurements of each source were obtained at two or more radio frequencies from surveys and catalogs to calculate their radio spectral indices {alpha}. The sources with a flat-radio spectrum ({alpha} {le} 0.5) were selected for the catalog, and the final catalog includes about 200 sources.

We report orientation-specific, surface-sensitive structural characterization of colloidal CdSe nanorods with extended X-ray absorption fine structure spectroscopy and ab-initio density functional theory calculations. Our measurements of crystallographically-aligned CdSe nanorods show that they have reconstructed Cd-rich surfaces. They exhibit orientation-dependent changes in interatomic distances which are qualitatively reproduced by our calculations. These calculations reveal that the measured interatomic distance anisotropy originates from the nanorod surface.

The authors present a measurement of the branching fraction of the decay B{sup 0} {yields} a{sub 1}{sup {+-}}(1260){pi}{sup {-+}} with a{sub 1}{sup {+-}}(1260) {yields} {pi}{sup {-+}}{pi}{sup {+-}}{pi}{sup {+-}}. The data sample corresponds to 218 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation through the {Upsilon}(4S) resonance. The authors measure the branching fraction {Beta}(B{sup 0} {yields} a{sub 1}{sup {+-}}(1260){pi}{sup {-+}}){Beta}(a{sub 1}{sup {+-}}(1260){yields} {pi}{sup {-+}}{pi}{sup {+-}}{pi}{sup {+-}})=(16.6 {+-} 1.9 {+-} 1.5) x 10{sup -6}, where the first error quoted is statistical and the second is systematic.

The authors report the first observation of e{sup +}e{sup -} annihilations into states of positive C-parity, namely {rho}{sup 0}{rho}{sup 0} and {phi}{rho}{sup 0}. The two states are observed in the {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} and K{sup +}K{sup -} {pi}{sup +}{pi}{sup -} final states, respectively, in a data sample of 225 fb{sup -1} collected by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage rings at energies near {radical}s = 10.58 GeV. The distributions of cos {theta}*, where {theta}* is the center-of-mass polar angle of the {phi} meson or the forward {rho}{sup 0} meson, suggest production by two-virtual-photon annihilation. They measure cross sections within the range |cos {theta}*| < 0.8 of {sigma}(e{sup +}e{sup -} {yields} {rho}{sup 0} {rho}{sup 0}) = 20.7 {+-} 0.7(stat) {+-} 2.7(syst) fb and {sigma}(e{sup +}e{sup -} {yields} {phi}{rho}{sup 0}) = 5.7 {+-} 0.5(stat) {+-} 0.8(syst) fb.

With the BABAR detector at the PEP-II asymmetric B Factory at SLAC, they present the first search for the decays B{sup 0} {yields} {ell}{sup +}{ell}{sup -}{gamma} ({ell} = e, {mu}). Using a data set of 292 fb{sup -1} collected at the {Upsilon}(4S) resonance, they find no significant signal and set the following branching fraction upper limits at 90% confidence level: {Beta}(B{sup 0} {yields} e{sup +}e{sup -}{gamma}) < 0.7 x 10{sup -7} and {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}{gamma}) < 3.4 x 10{sup -7}.

The authors present the first search for the decay B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0} using a data sample of 232 million B{bar B} pairs. They find no statistically significant evidence for the non-resonant component of this decay. Our central value for the branching fraction, assuming the tru Dalitz distribution is uniform and excluding the {phi} resonance, is {Beta}(B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0}) = (2.4{sub -2.5}{sup +2.7} {+-} 0.6) x 10{sup -6} where the errors are statistical and systematic, respectively. They set a single-side Bayesian upper limit of {Beta}(B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0}) < 6.4 x 10{sup -6} at 90% confidence level using a uniform prior probability for physical values. Assuming the worst-case true Dalitz distribution, where the signal is entirely in the region of lowest efficiency, the 90% confidence level upper limit is {Beta}(B{sup 0} {yields} K{sub S}{sup 0} K{sub S}{sup 0} K{sub L}{sup 0}) < 14 x 10{sup -6}.

The authors present a search for the decay of a B{sup 0} or {bar B}{sup 0} meson to a {bar K}*{sup 0} K{sup 0} or K*{sup 0} {bar K}{sup 0} final state, using a sample of approximately 232 million B{bar B} events collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} collider at SLAC. The measured branching fraction is {Beta}(B{sup 0} {yields} {bar K}*{sup 0} K{sup 0}) + {Beta}(B{sup 0} {yields} K*{sup 0} {bar K}{sup 0}) = (0.2{sub -0.8, -0.3}{sup +0.9, +0.1}) x 10{sup -6}. They obtain the following upper limit for the branching fraction at 90% confidence level: {Beta}(B{sup 0} {yields} {bar K}*{sup 0} K{sup 0}) + {Beta}(B{sup 0} {yields} K*{sup 0} {bar K}{sup 0}) < 1.9 x 10{sup -6}. They use our result to constrain the Standard Model prediction for the deviation of the CP asymmetry in B{sup 0} {yields} {phi}K{sup 0} from sin 2{beta}.

The resummation of soft gluon exchange for QCD hard scattering requires a matrix of anomalous dimensions. We compute this matrix directly for arbitrary 2 {yields} n massless processes for the first time at two loops. Using color generator notation, we show that it is proportional to the one-loop matrix. This result reproduces all pole terms in dimensional regularization of the explicit calculations of massless 2 {yields} 2 amplitudes in the literature, and it predicts all poles at next-to-leading order in any 2 {yields} n process that has been computed at next-to-leading order. The proportionality of the one- and two-loop matrices makes possible the resummation in closed form of the next-to-next-to-leading logarithms and poles in dimensional regularization for the 2 {yields} n processes.

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A unique electronics system has been built and tested for reading signals from the silicon-strip detectors of the Gamma-ray Large Area Space Telescope mission. The system amplifies and processes signals from 884,736 36-cm strips using only 160 W of power, and it achieves close to 100% detection efficiency with noise occupancy sufficiently low to allow it to self trigger. The design of the readout system is described, and results are presented from ground-based testing of the completed detector system.

Reflectivity measurements in the far infrared, performed on aluminum and copper samples, are presented and analyzed. Over a frequency range of interest for the LCLS bunch, the data is fit to the free-electron model, and to one including the anomalous skin effect. The models fit well, yielding parameters dc conductivity and relaxation times that are within 30-40% of expected values. We show that the induced energy in the LCLS undulator region is relatively insensitive to variations on this order, and thus we can have confidence that the wake effect will be close to what is expected.

The measurement of the branching fraction of the flavor changing neutral current B {yields} X{sub s}{gamma} transition can be used to expose physics outside the Standard Model. In order to make a precise measurement of this inclusive branching fraction, it is necessary to be able to effectively separate signal and background in the data. In order to achieve better separation, an algorithm based on Boosted Decision Trees (BDTs) is implemented. Using Monte Carlo simulated events, ''forests'' of trees were trained and tested with different sets of parameters. This parameter space was studied with the goal of maximizing the figure of merit, Q, the measure of separation quality used in this analysis. It is found that the use of 1000 trees, with 100 values tested for each variable at each node, and 50 events required for a node to continue separating give the highest figure of merit, Q = 18.37.

This article reports world averages for measurements on b-hadron properties obtained by the Heavy Flavor Averaging Group (HFAG) using the available results as of at the end of 2005. In the averaging, the input parameters used in the various analyses are adjusted (rescaled) to common values, and all known correlations are taken into account. The averages include lifetimes, neutral meson mixing parameters, parameters of semileptonic decays, branching fractions of B decays to final states with open charm, charmonium and no charm, and measurements related to CP asymmetries.

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We report high pressure dynamic compression experiments of liquid water along a quasi-adiabatic path leading to the formation of ice VII. We observe dynamic features resembling Van der Waals loops and find that liquid water is compacted to a metastable state close to the ice density before the onset of crystallization. By analyzing the characteristic kinetic time scale involved we estimate the nucleation barrier and conclude that liquid water has been compressed to a high pressure state close to its thermodynamic stability limit.

This report summarizes the data analysis achieved during Heather Bedle's eleven-week Technical Scholar internship at Lawrence Livermore National Labs during the early summer 2006. The work completed during this internship resulted in constraints on the crustal and upper mantle S-velocity structure in Northern Africa, the Mediterranean, the Middle East, and Europe, through the fitting of regional waveform data. This data extends current raypath coverage and will be included in a joint inversion along with data from surface wave group velocity measurements, S and P teleseismic arrival time data, and receiver function data to create an improved velocity model of the upper mantle in this region. The tectonic structure of the North African/Mediterranean/Europe/Middle Eastern study region is extremely heterogeneous. This region consists of, among others, stable cratons and platforms such as the West Africa Craton, and Baltica in Northern Europe; oceanic subduction zones throughout the Mediterranean Sea where the African and Eurasian plate collide; regions of continental collision as the Arabian Plate moves northward into the Turkish Plate; and rifting in the Red Sea, separating the Arabian and Nubian shields. With such diverse tectonic structures, many of the waveforms were difficult to fit. This is not unexpected as the waveforms are …

A search for nuclear resonance fluorescence excitations in {sup 235}U and {sup 239}Pu within the energy range of 1.0- to 2.5-MeV was performed using a 4-MeV continuous bremsstrahlung source at the High Voltage Research Laboratory at the Massachusetts Institute of Technology. Measurements utilizing high purity Ge detectors at backward angles identified 9 photopeaks in {sup 235}U and 12 photopeaks in {sup 239}Pu in this energy range. These resonances provide unique signatures that allow the materials to be non-intrusively detected in a variety of environments including fuel cells, waste drums, vehicles and containers. The presence and properties of these states may prove useful in understanding the mechanisms for mixing low-lying collective dipole excitations with other states at low excitations in heavy nuclei.

The following report documents the technical approach and conclusions made by Acumentrics Corporation during latest budget period toward the development of a low cost 10kW tubular SOFC power system. The present program, guided under direction from the National Energy Technology Laboratory of the US DOE, is a nine-year cost shared Cooperative Agreement totaling close to $74M funded both by the US DOE as well as Acumentrics Corporation and its partners. The latest budget period ran from January of 2006 through June 2006. Work focused on cell technology enhancements as well as BOP and power electronics improvements and overall system design. Significant progress was made in increasing cell power enhancements as well as decreasing material cost in a drive to meet the SECA cost targets. The following report documents these accomplishments in detail as well as the layout plans for further progress in next budget period.

This document contains the calendar year 2006 schedules for the routine and non-routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project. Each section includes sampling locations, sample types, and analyses to be performed. In some cases, samples are scheduled on a rotating basis and may not be collected in 2006 in which case the anticipated year for collection is provided. The project document package (PDP) for Surface Environmental Surveillance contains the milestone control log for the issuing of CY06 Environmental Surveillance Master Sampling Schedule WBS 4.2.3.21.3.03, milestone: RL00430306 (4830106-12).

Standard jet finding techniques used in elementary particle collisions have not been successful in the high track density of heavy-ion collisions. This paper describes a modified cone-type jet finding algorithm developed for the complex environment of heavy-ion collisions. The primary modification to the algorithm is the evaluation and subtraction of the large background energy, arising from uncorrelated soft hadrons, in each collision. A detailed analysis of the background energy and its event-by-event fluctuations has been performed on simulated data, and a method developed to estimate the background energy inside the jet cone from the measured energy outside the cone on an event-by-event basis. The algorithm has been tested using Monte-Carlo simulations of Pb+Pb collisions at {radical}s = 5.5 TeV for the ALICE detector at the LHC. The algorithm can reconstruct jets with a transverse energy of 50 GeV and above with an energy resolution of {approx} 30%.