We present three recent analyses (Abstracts 169, 170 and 174) of the mass of the top quark (M{sub t}) using top-antitop candidate events collected by the D0 experiment at the Fermilab Tevatron Collider: (i) a 3.6 events/fb sample of data in the lepton+jets channel analyzed to extract a precision value of M{sub t} using the 'Matrix-Element' (ME) method, wherein each event probability is calculated from the differential production cross section as a function of M{sub t} and the overall jet energy scale, with the latter constrained by the two jets from W decay into q{prime}{bar q}, (ii) a first measurement of the mass difference between top and antitop quarks as a check of CPT invariance in the quark sector, also based on the ME method in lepton+jets channels, and corresponding to a 1 event/fb data sample, and (iii) measurements of M{sub t} in dilepton final states (updated to 3.6 events/fb), based on 'matrix' weighting, 'neutrino' weighting and the ME method, which rely, respectively, on the likelihood of observing the events in data for a range of assumed M{sub t} values, distributions generated from event weights that compare calculated and reconstructed missing transverse energies, and event probabilities based on the leading-order …

The vibrational spectra of platinum nanoparticles (12 nm) capped with tetradecyltrimethylammonium bromide, C{sub 14}TAB, were investigated by Fourier transform infrared (FTIR) spectroscopy. We have shown that the thermal decay of Pt-C{sub 14}TAB nanoparticles in N{sub 2}, H{sub 2} and O{sub 2} atmospheres leads to the release of hydrocarbon chain of surfactant and the formation of strongly bonded layer of ammonium cations on the platinum surface. The platinum atoms accessible to CO chemisorptions were not reducible by hydrogen in the temperature ranging from 30 C to 200 C. A FTIR spectrum of C{sub 14}TAB adsorbed on Pt nanoparticles dramatically perturbed as compared with pure C{sub 14}TAB. New intense and broad bands centered at 1450 cm{sup -1} and 760 cm{sup -1} are making their appearance in Pt-C{sub 14}TAB. It may be speculated, that new bands are result of coupling between conducting electrons of Pt and molecular vibrations of adsorbed C{sub 14}TAB and as a consequence specific vibrational modes of ammonium cation transformed into electron-vibrational modes.

We developed, tested, and now operate a civilian biological defense capability that continuously monitors the air for biological threat agents. The Autonomous Pathogen Detection System (APDS) collects, prepares, reads, analyzes, and reports results of multiplexed immunoassays and multiplexed PCR assays using Luminex{copyright} xMAP technology and flow cytometer. The mission we conduct is particularly demanding: continuous monitoring, multiple threat agents, high sensitivity, challenging environments, and ultimately extremely low false positive rates. Here, we introduce the mission requirements and metrics, show the system engineering and analysis framework, and describe the progress to date including early development and current status.

It can be computationally advantageous to perform computer simulations in a Lorentz boosted frame for a certain class of systems. However, even if the computer model relies on a covariant set of equations, it has been pointed out that algorithmic difficulties related to discretization errors may have to be overcome in order to take full advantage of the potential speedup. We summarize the findings, the difficulties and their solutions, and show that the technique enables simulations important to several areas of accelerator physics that are otherwise problematic, including self-consistent modeling in three-dimensions of laser wokefield accelerator stages at energies of 10 GeV and above.

Fermilab began exploring the technologies for vertically integrated circuits (also commonly known as 3D circuits) in 2006. These technologies include through silicon vias (TSV), circuit thinning, and bonding techniques to replace conventional bump bonds. Since then, the interest within the High Energy Physics community has grown considerably. This paper will present an overview of the activities at Fermilab over the last 3 years which have helped spark this interest.

We describe how jets and E{sub T} are defined, reconstructed, and calibrated in CMS, as well as how the CMS detector performs in measuring these physics objects. Performance results are derived from the CMS simulation application, based on Geant4, and also from noise and cosmic commissioning data taken before the first collision event was recorded by CMS in November 2009. A jet and E{sub T} startup plan is in place which includes a data quality monitoring and prompt analysis task force to identify and fix problems as they arise.

We present observation of electroweak single top quark production using 3.2 fb{sup -1} of data collected by the CDF experiment. Candidate events are selected for further classification by five parallel analysis techniques: one using a likelihood discriminant, one using a matrix-element discriminant, one using decision trees, one using a neural network, and one using a complementary dataset. The results of these analyses are combined in order to improve the expected sensitivity. The significance of the observed data is 5.0 standard deviations, and the expected sensitivity is in excess of 5.9 standard deviations. We also present the most current value of the CKM matrix element |V{sub tb}|.

We present a new expected upper limit of the rare decay branching ratio B{sub s} {yields} {mu}{sup +}{mu}{sup -} using about 5 fb{sup -1} of Run II data collected with the D0 detector at the Tevatron. When setting limits on the branching ratio, selected events are normalized to reconstructed B{sup {+-}} {yields} J/{Psi}K{sup {+-}} events in order to decrease the systematic uncertainty. The resulting expected upper limit is {Beta}(B{sub s} {yields} {mu}{sup +}{mu}{sup -}) = 4.3(5.3) x 10{sup -8} at the 90% (95%) C.L.

An internal R&D project was conducted at the Special Technologies Laboratory (STL) of National Security Technologies, LLC (NSTec), to determine the feasibility of developing a multi-layer boron-10 based thermal neutron detector using the amorphous silicon (AS) technology currently employed in the manufacture of liquid crystal displays. The boron-10 neutron reaction produces an alpha that can be readily detected. A single layer detector, limited to an approximately 2-micron-thick layer of boron, has a theoretical sensitivity of about 3%; hence a thin multi-layer device with high sensitivity can theoretically be manufactured from single layer detectors. Working with National Renewable Energy Laboratory (NREL), an AS PiN diode alpha detector was developed and tested. The PiN diode was deposited on a boron-10 coated substrate. Testing confirmed that the neutron sensitivity was nearly equal to the theoretical value of 3%. However, adhesion problems with the boron-10 coating prevented successful development of a prototype detector. Future efforts will include boron deposition work and development of integrated AS signal processing circuitry.

We present measurements of the linear polarization amplitudes and the strong relative phases that describe the flavor-untagged decays B{sub d} {yields} J/{Psi} K* and B{sub s} {yields} J/{Psi}{phi} in the transversity basis. We also measure the mean lifetime of the B{sub s} mass eigenstates and the lifetime ratio. The analyses are based on approximately 2.8 fb{sup -1} of data recorded with the D0 detector. From our measurements of the angular parameters we conclude that there is no evidence for a deviation from flavor SU(3) symmetry for these decays and that the factorization assumption is not valid for the B{sub d} {yields} J/{Psi} K* decay.

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We present recent CDF results on the properties of hadrons containing heavy quarks. These include the measurements of mass, lifetime and relative cross section of the B{sub c} meson and an updated measurement of the B{sub s}{sup 0} and {Lambda}{sub b}{sup 0} lifetime. We also summarize new measurements of the mass of the {Sigma}{sub b} baryon. We expect more results from the Tevatron which will accumulate more data until the end of Run II currently scheduled to conclude in 2010.

We present a search for a low mass Standard Model Higgs boson produced in association with a Z boson decaying invisibly into a pair of neutrinos at a center-of-mass energy of {radical}s = 1.96 TeV with the D0 detector at the Fermilab Tevatron collider. The final state is characterized by the presence of two b-tagged jets from the Higgs boson decay and a large imbalance in the transverse energy of the event. This channel is very powerful because of the large Z {yields} {nu}{anti {nu}} branching ratio, but also has many experimental challenges due to the large multijet background and the absence of visible carged leptons in the final state. We present the result with 5.2 fb{sup -1} of data and discuss the recent improvements in the sensitivity.

The MINOS experiment utilizes the NuMI beam of muon neutrinos to study the phenomenon of neutrino oscillations. Neutrinos are sent over a baseline of 735 km, with a detector near the production point at Fermilab and one at the Soudan underground laboratory in northern Minnesota. By measuring the disappearance characteristic of oscillations, MINOS has made the best measurement of the atmospheric neutrino mass splitting to date. By looking for electron neutrino appearance, a limit has been placed on the the mixing angle sin{sup 2}(2{theta}{sub 13}) of < 0.29 at 90% c.l. (for {delta}{sub CP} = 0 and normal mass hierarchy). A study of neutral current interactions has allowed limits to be placed on the existence of additional, sterile neutrino flavours beyond the three of the standard oscillation model. Using the 7% muon antineutrino component of the beam, the first direct observation of muon antineutrinos in a long baseline experiment has been made, along with direct limits on the antineutrino oscillation parameters. In September 2009, the current in the NuMI focusing horns will be reversed to begin running with a dedicated antineutrino beam. This will allow the first precision measurements of the atmospheric-regime antineutrino oscillation parameters, an important test of CPT-invariance …

Under certain theoretical assumptions, the branching fraction of B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-} is directly sensitive to the relative decay width difference {Delta}{Lambda}{sub s}{sup CP}/{Lambda}{sub s} in the B{sub s}{sup 0} system, which is predicted to be sizable in the standard model. Using approximately 4 fb{sup -1} of data collected by the CDF II detector at the Tevatron p{bar p} collider, the CDF collaboration is currently performing an exclusive selection of B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-} signal candidates in several hadronic modes in order to provide a new branching fraction measurement. In contrast to former analyses, we start to have sensitivity in disentangling D{sub s}{sup (*)+}D{sub s}{sup (*)-}, enabling us to measure the branching fractions of B{sub s}{sup 0} {yields} D{sub s}{sup +}D{sub s}{sup -}, B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup -} and B{sub s}{sup 0} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-} separately. Yet another interesting mode is the decay of the B{sub s}{sup 0} into a {phi} pair. This is a vector-vector decay dominated by the b {yields} s{ovr ss} penguin transition, which is a sensitive probe for possible new physics effects. Here we present a new measurement of …

The development of monodisperse crystalline particles in cordierite glass doped with Cr3+ after a two-step heat treatment is elucidated by a combination of time-resolved small and wide angle x-ray scattering (SAXS/WAXS) experiments with electron microscopy. The effects of bulk and surface crystallization can clearly be distinguished, and the crystallization kinetics of the bulk phase is characterized. The internal pressure due to structural differences between the crystalline and amorphous phase is measured but the physical cause of this pressure can not unambiguously be attributed. The combined measurements comprise a nearly full characterization of the crystallization processes and the resulting sample morphology.

Many extensions of the Standard Model, other that Supersymmetry, predict the existence of new heavy resonances or heavy quarks, the existence of extra dimensions which will manifest themselves by the presence of gravitons states, or a possible compositeness of quarks and leptons. Results of some of the 'Beyond Standard Model' searches made by the CDF and D0 collaborations at the Tevatron are presented. These analyses are using data corresponding to an integrated luminosity up to 4.1 fb{sup -1}. Searches for Z{prime}, W{prime}, graviton, a new quark b{prime}, quark compositeness, Leptoquarks or new long-lived particles are described here.

The CDF and D0 Collaborations at the Tevatron have an extensive program of searches for 'Beyond-the-Standard-Model' Higgs bosons. Recent results, using data sets corresponding to integrated luminosities of up to 4.2 fb{sup -1}, from such searches are reported. Good agreement between data and Standard Model backgrounds is found in all of the various final states examined. We thus proceed to set limits at 95% Confidence Level (C.L.).

The new reaction 208Pb(59Co,n)266Mt was studied using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. A cross section of 7.7+5.2-3.3 pb was measured at a compound nucleus excitation energy of 14.9 MeV. The measured decay properties of 266Mt and its daughters correspond well with existing data. We compare this experimental result to transactinide compound nucleus formation model predictions, and the previously studied 209Bi(58Fe,n)266Mt reaction.

The quantification of carbon fluxes between the terrestrial biosphere and the atmosphere is of scientific importance and also relevant to climate-policy making. Eddy covariance flux towers provide continuous measurements of ecosystem-level exchange of carbon dioxide spanning diurnal, synoptic, seasonal, and interannual time scales. However, these measurements only represent the fluxes at the scale of the tower footprint. Here we used remotely-sensed data from the Moderate Resolution Imaging Spectroradiometer (MODIS) to upscale gross primary productivity (GPP) data from eddy covariance flux towers to the continental scale. We first combined GPP and MODIS data for 42 AmeriFlux towers encompassing a wide range of ecosystem and climate types to develop a predictive GPP model using a regression tree approach. The predictive model was trained using observed GPP over the period 2000-2004, and was validated using observed GPP over the period 2005-2006 and leave-one-out cross-validation. Our model predicted GPP fairly well at the site level. We then used the model to estimate GPP for each 1 km x 1 km cell across the U.S. for each 8-day interval over the period from February 2000 to December 2006 using MODIS data. Our GPP estimates provide a spatially and temporally continuous measure of gross primary production …

An overview of the most recent experimental results on Branching Fractions of rare fully leptonic B decays is given; constraints on the parameters of some New Physics models are presented. Perspectives with new accelerator programs are discussed.

We present the results of searches for non-standard model phenomena in photon final states. These searches use data from integrated luminosities of {approx} 1-4 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the CDF and D0 detectors at the Fermilab Tevatron. No significant excess in data has been observed. We report limits on the parameters of several BSM models (excluding SUSY) for events containing photons.

Isotope distributions in natural systems can be highly sensitive to the mass (m) dependence of solute diffusion coefficients (D) in liquid water. Isotope geochemistry studies routinely have assumed that this mass dependence either is negligible (as predicted by hydrodynamic theories) or follows a kinetic-theory-like inverse square root relationship (D {proportional_to} m{sup -0.5}). However, our recent experimental results and molecular dynamics (MD) simulations showed that the mass dependence of D is intermediate between hydrodynamic and kinetic theory predictions (D {proportional_to} m{sup -{beta}} with 0 {<=} {beta} < 0.2 for Li{sup +}, Cl{sup -}, Mg{sup 2+}, and the noble gases). In this paper, we present new MD simulations and experimental results for Na{sup +}, K{sup +}, Cs{sup +}, and Ca{sup 2+} that confirm the generality of the inverse power-law relation D {proportional_to} m{sup -{beta}}. Our new findings allow us to develop a general description of the influence of solute valence and radius on the mass dependence of D for monatomic solutes in liquid water. This mass dependence decreases with solute radius and with the magnitude of solute valence. Molecular-scale analysis of our MD simulation results reveals that these trends derive from the exponent {beta} being smallest for those solutes whose motions are …

The interaction between slow highly-charged ions (SHCI) of different charge states from an electron-beam ion trap and highly oriented pyrolytic graphite (HOPG) surfaces is studied in terms of modification of electronic states at single-ion impact nanosizeareas. Results are presented from AFM/STM analysis of the induced-surface topological features combined with Raman spectroscopy. I-V characteristics for a number of different impact regions were measured with STM and the results argue for possible formation of diamond-like nanoscale structures at the impact sites.