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We present a study of events with Z bosons and jets produced at the Fermilab Tevatron Collider in p{bar p} collisions at a center of mass energy of 1.96 TeV. The data sample consists of nearly 14,000 Z/{gamma}* {yields} e{sup +}e{sup -} candidates corresponding to the integrated luminosity of 340 pb{sup -1} collected using the D0 detector. Ratios of the Z/{gamma}* + {ge} n jet cross sections to the total inclusive Z/{gamma}* cross section have been measured for n = 1 to 4 jet events. Our measurements are found to be in good agreement with a next-to-leading order QCD calculation and with a tree-level QCD prediction with parton shower simulation and hadronization.

A search for direct production of scalar bottom quarks ({bar b}) is performed with 310 pb{sup -1} of data collected by the D0 experiment in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron Collider. The topology analyzed consists of two b jets and an imbalance in transverse momentum due to undetected neutralinos ({tilde {chi}}{sub 1}{sup 0}), with {tilde {chi}}{sub 1}{sup 0} assumed to be the lightest supersymmetric particle. They find the data consistent with standard model expectations, and set a 95% C.L. exclusion domain in the (m{sub {tilde b}}, m{sub {tilde {chi}}}) mass plane, improving significantly upon the results from Run I of the Tevatron.

We report a measurement of the longitudinal double-spinasymmetry A_LL and the differential cross section for inclusivemidrapidity jet production in polarized proton collisions at sqrt(s)=200GeV. The cross section data cover transverse momenta 5<pT<50GeV/c and agree with next-to-leading order perturbative QCD evaluations.The A_LL data cover 5<pT<17 GeV/c and disfavor at 98 percentC.L. maximal positive gluon polarization in the polarizednucleon.

We present the first statistically meaningful results fromtwo-K0s interferometry in heavy-ion collisions. A model that takes theeffect of the strong interaction into account has been used to fit themeasured correlation function. The effects of single and coupled channelwere explored. At the mean transverse mass m_T = 1.07 GeV, we obtain thevalues R = 4.09 +- 0.46 (stat.) +- 0.31 (sys) fm and lambda = 0.92 +-0.23 (stat) +- 0.13 (sys), where R and lambda are the invariant radiusand chaoticity parameters respectively. The results are qualitativelyconsistent with m_T systematics established with pions in a scenariocharacterized by a strong collective flow.

The polarization of {Xi}{sup 0} and {bar {Xi}}{sup 0} hyperons produced by 800 GeV/c protons on a BeO target at a fixed targeting angle of 4.8 mrad is measured by the KTeV experiment at Fermilab. The result of 9.7% for {Xi}{sup 0} polarization shows no significant energy dependence when compared to a result obtained at 400 GeV/c production energy and at twice the targeting angle. The polarization of the {Xi}{sup 0} is measured for the first time and found to be consistent with zero. They also examine the dependence of polarization on production p{sub t}.

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The authors report an upper limit on the fraction of V + A current, f{sub V+A}, in top quark decays, using approximately 700 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV acquired by the upgraded Collider Detector at Fermilab. For the decay t {yields} wb {yields} {ell}vb (where {ell} = e or {mu}), the invariant mass of the charged lepton and the bottom quark jet is sensitive to the polarization of the W boson. They determine f{sub V+A} = -0.06 {+-} 0.25 given a top quark mass of 175 GeV/c{sup 2}. They set an upper limit on f{sub V+A} of 0.29 at the 95% confidence level, which represents an improvement by a factor of two on the previous best direct limit.

We have developed an artificial neural network (ANN) based combustion model and have integrated it into a fluid mechanics code (KIVA3V) to produce a new analysis tool (titled KIVA3V-ANN) that can yield accurate HCCI predictions at very low computational cost. The neural network predicts ignition delay as a function of operating parameters (temperature, pressure, equivalence ratio and residual gas fraction). KIVA3V-ANN keeps track of the time history of the ignition delay during the engine cycle to evaluate the ignition integral and predict ignition for each computational cell. After a cell ignites, chemistry becomes active, and a two-step chemical kinetic mechanism predicts composition and heat generation in the ignited cells. KIVA3V-ANN has been validated by comparison with isooctane HCCI experiments in two different engines. The neural network provides reasonable predictions for HCCI combustion and emissions that, although typically not as good as obtained with the more physically representative multi-zone model, are obtained at a much reduced computational cost. KIVA3V-ANN can perform reasonably accurate HCCI calculations while requiring only 10% more computational effort than a motored KIVA3V run. It is therefore considered a valuable tool for evaluation of engine maps or other performance analysis tasks requiring multiple individual runs.

Since the ITRP recommendation in August 2004 to use superconducting rf technology for a next generation linear collider, the former NLC Group at SLAC has been actively pursuing a broad range of R&amp;D for this collider (the ILC). In this paper, the programs concerning linac technology are reviewed. Current activities include the development of a Marx-style modulator and a 10 MW sheet-beam klystron, operation of an L-band (1.3 GHz) rf source using an SNS HVCM modulator and commercial klystrons, design of a more efficient and less costly rf distribution system, construction of a coupler component test stand, fabrication of a prototype positron capture cavity, beam tests of prototype S-band linac beam position monitors and preparations for magnetic center stability measurements of a prototype SC linac quad.

We study top quark flavor violation in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. Such a scenario provides solutions to both the Planck-weak hierarchy problem and the flavor puzzle of the SM without inducing a flavor problem. We find that, generically, tcZ couplings receive a huge enhancement, in particular the right handed ones can be {Omicron}(1%). This results in BR (t {yields} cZ) at or above the sensitivity of the Large Hadron Collider (LHC). At the International Linear Collider (ILC), single top production, via e{sup +}e{sup -} {yields} t{bar c}, can be a striking signal for this scenario. In particular, it represents a physics topic of critical importance that can be explored even with a relatively low energy option, close to the tc threshold. At both the LHC and the ILC, angular distributions can probe the above prediction of dominance of right-handed couplings.

A search has been made for neutrinos from the hep reactionin the Sun and from the diffuse supernova neutrino background (DSNB)using data collected during the first operational phase of the SudburyNeutrino Observatory, with an exposure of 0.65 kilotonne-years. For thehep neutrino search, two events are observed in the effective electronenergy range of 14.3 MeV<Teff<20 MeV where 3.1 backgroundevents are expected. After accounting for neutrino oscillations, an upperlimit of 2.3 x 104 cm-2s-1 at the 90 percent confidence level is inferredon the integral total flux of hep neutrinos. For DSNB neutrinos, noevents are observed in the effective electron energy range of 21 MeV<Teff<35 MeV and, consequently, an upper limit on the nu e componentof the DSNB fluxin the neutrino energy range of 22.9 MeV<E nu<36.9 MeV of 70 cm-2-1 is inferred at the 90 percent confidence level.This is an improvement by a factor of 6.5 on the previous best upperlimit on the hep neutrino flux and by two orders of magnitude on theprevious upper limit on the nu e component of the DSNB flux.

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.

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The LHC Accelerator Research Program (LARP) has a primary goal to develop, assemble, and test full size Nb{sub 3}Sn quadrupole magnet models for a luminosity upgrade of the Large Hadron Collider (LHC). A major milestone in this development is to assemble and test, by the end of 2009, two 4m-long quadrupole cold masses, which will be the first Nb3Sn accelerator magnet models approaching the length of real accelerator magnets. The design is based on the LARP Technological Quadrupoles (TQ), under development at FNAL and LBNL, with gradient higher than 200 T/m and aperture of 90 mm. The mechanical design will be chosen between two designs presently explored for the TQs: traditional collars and Al-shell based design (preloaded by bladders and keys). The fabrication of the first long quadrupole model is expected to start in the last quarter of 2007. Meanwhile the fabrication of 4m-long racetrack coils started this year at BNL. These coils will be tested in an Al-shell based supporting structure developed at LBNL. Several challenges have to be addressed for the successful fabrication of long Nb{sub 3}Sn coils. This paper presents these challenges with comments and solutions adopted or under study for these magnets. The coil design of …

An optimization method based on the evaluation of a broad range of different combinations of specific energy efficiency and renewable-energy options is used to determine the least-cost pathway to the development of new homes with zero peak cooling demand. The optimization approach conducts a sequential search of a large number of possible option combinations and uses the most cost-effective alternatives to generate a least-cost curve to achieve home-performance levels ranging from a Title 24-compliant home to a home that uses zero net source energy on an annual basis. By evaluating peak cooling load reductions on the least-cost curve, it is then possible to determine the most cost-effective combination of energy efficiency and renewable-energy options that both maximize annual energy savings and minimize peak-cooling demand.

Fermilab's cabling facility has been upgraded to a maximum capability of 42 strands. This facility is being used to study the effect of cabling on the performance of the various strands, and for the development and fabrication of cables in support of the ongoing magnet R&amp;D programs. Rutherford cables of various geometries, packing factors, with and without a stainless steel core, were fabricated out of Cu alloys, NbTi, Nb{sub 3}Al, and various Nb{sub 3}Sn strands. The parameters of the upgraded cabling machine and results of cable R&amp;D efforts at Fermilab are reported.

A helical cooling channel has been proposed to quickly reduce the six-dimensional phase space of muon beams for muon colliders, neutrino factories, and intense muon sources. A novel superconducting magnet system for a muon beam cooling experiment is being designed at Fermilab. The inner volume of the cooling channel is filled with liquid helium where passing muon beam can be decelerated and cooled in a process of ionization energy loss. The magnet parameters are optimized to match the momentum of the beam as it slows down. The results of 3D magnetic analysis for two designs of magnet system, mechanical and quench protection considerations are discussed.

CP violation in B{sup 0}{bar B}{sup 0} mixing is characterized by the value of the parameter |q/p| being different from 1, and the Standard Model predicts this difference to be smaller than 10{sup -3}. We present a measurement of this parameter using a partial reconstruction of one of the B mesons in the semileptonic channel D*{sup -}{ell}{sup +}{nu}{sub {ell}}, where only the hard lepton and the soft pion from the D*{sup -} {yields} {bar D}{sup 0}{pi}{sup -} decay are reconstructed. The flavor of the other B is determined by means of lepton tagging. The determination of |q/p| is then performed with a fit to the proper time difference of the two B decays. We use a luminosity of 200.8 fb{sup -1}, collected at the {Upsilon}(4S) resonance by the BABAR detector at the PEP-II asymmetrical-energy e{sup +}e{sup -} collider, in the period 1999-2004. We obtain the preliminary result: |q/p| - 1 = (6.5 {+-} 3.4(stat.) {+-} 2.0(syst.)) {center_dot} 10{sup -3}.

We perform the first three-dimensional measurement of the amplitudes of B {yields} {psi}(2S)K* and B {yields} {chi}{sub c1}K* decays and update our previous measurement for B {yields} J/{psi} K*. We use a data sample collected with the BABAR detector at the PEP-II storage ring, representing 232 million produced B{bar B} pairs. The longitudinal polarization of decays to the 1{sup ++} {chi}{sub c1} meson together with a K* meson, is found to be larger than that for the decay to the 1{sup --} {Psi} mesons. No direct CP-violating charge asymmetry is observed.

We report a measurement of the B {yields} {pi}{ell}{nu} branching fraction based on 211 fb{sup -1} of data collected with the BABAR detector. We use samples of B{sup 0} and B{sup +} mesons tagged by a second B meson reconstructed in a semileptonic or hadronic decay, and combine the results assuming isospin symmetry to obtain {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.33 {+-} 0.17{sub stat} {+-} 0.11{sub syst}) x 10{sup -4}. We determine the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}| by combining the partial branching fractions measured in ranges of the momentum transfer squared and theoretical calculations of the form factor. Using a recent lattice QCD calculation, we find |{sub ub}| = (4.5 {+-} 0.5{sub stat} {+-} 0.3{sub syst} {sub -0.5}{sup +0.7}FF) x 10{sup -3}, where the last error is due to the normalization of the form factor.

The authors present a measurement of the branching fraction and time-dependent CP asymmetry of B{sup 0} {yields} {rho}{sup 0}K{sup 0}. The results are obtained from a data sample of 227 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. From a time-dependent maximum likelihood fit yielding 111 {+-} 19 signal events they find {Beta}(B{sup 0} {yields} {rho}{sup 0}K{sup 0}) = (4.9 {+-} 0.8 {+-} 0.9) x 10{sup -6}, where the first error is statistical and the second systematic. They report the measurement of the CP parameters S{sub {rho}{sup 0}K{sub S}{sup 0}} = 0.20 {+-} 0.52 {+-} 0.24 and C{sub {rho}{sup 0}K{sub S}{sup 0}} = 0.64 {+-} 0.41 {+-} 0.20.

The authors present an updated measurement of the time-dependent CP-violating asymmetry in B{sup 0} {yields} K{sub S}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0} decays based on 347 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. The authors obtain the CP asymmetries S{sub f} = -0.66 {+-} 0.26 {+-} 0.08 and C{sub f} = -0.14 {+-} 0.22 {+-} 0.05, where the first uncertainties are statistical and the second systematic.