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Simulation of Alpha-Channeling in Mirror Machines (open access)

Simulation of Alpha-Channeling in Mirror Machines

Applying α-channeling techniques to mirror machines can significantly increase their effective reactivity, thus making open configurations more advantageous for practical fusion. A large fraction of α particle energy can be extracted using rf waves. Effects employed to cool α particles can also in principle be used to heat the fusion ions; the possibility to design a configuration of rf waves which could be used to perform both tasks is demonstrated.
Date: March 17, 2008
Creator: A.I. Zhmoginov, N.J. Fisch
Object Type: Report
System: The UNT Digital Library
NUCLEAR WASTE GLASSES CONTINUOUS MELTING AND BULK VITRIFICAITON (open access)

NUCLEAR WASTE GLASSES CONTINUOUS MELTING AND BULK VITRIFICAITON

This contribution addresses various aspects of nuclear waste vitrification. Nuclear wastes have a variety of components and composition ranges. For each waste composition, the glass must be formulated to possess acceptable processing and product behavior defined in terms of physical and chemical properties that guarantee the glass can be easily made and resist environmental degradation. Glass formulation is facilitated by developing property-composition models, and the strategy of model development and application is reviewed. However, the large variability of waste compositions presents numerous additional challenges: insoluble solids and molten salts may segregate; foam may hinder heat transfer and slow down the process; molten salts may accumulate in container refractory walls; the glass on cooling may precipitate crystalline phases. These problems need targeted exploratory research. Examples of specific problems and their possible solutions are discussed.
Date: March 24, 2008
Creator: AA, KRUGER & PR, HRMA
Object Type: Article
System: The UNT Digital Library
Search for Hadronic Decays of W and Z Bosons in Photon Events in p anti-p Collisions at s**(1/2) = 1.96-GeV (open access)

Search for Hadronic Decays of W and Z Bosons in Photon Events in p anti-p Collisions at s**(1/2) = 1.96-GeV

None
Date: March 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF (open access)

Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF

We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (p{bar p} {yields} W{sup {+-}}H {yields} {ell}{nu}b{bar b}) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector which correspond to an integrated luminosity of approximately 1 fb{sup -1}. We select events consistent with a signature of a single lepton (e{sup {+-}}/{mu}{sup {+-}}), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method and a neural network filter technique. The observed number of events and the dijet mass distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching ratio ranging from 3.9 to 1.3 pb for Higgs boson masses from 110 to 150 GeV/c{sup 2}, respectively.
Date: March 1, 2008
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type: Article
System: The UNT Digital Library
Evidence for production of single top quarks (open access)

Evidence for production of single top quarks

We present first evidence for the production of single top quarks in the D0 detector at the Fermilab Tevatron p{bar p} collider. The standard model predicts that the electroweak interaction can produce a top quark together with an antibottom quark or light quark, without the antiparticle top quark partner that is always produced from strong coupling processes. Top quarks were first observed in pair production in 1995, and since then, single top quark production has been searched for in ever larger datasets. In this analysis, we select events from a 0.9 fb{sup -1} dataset that have an electron or muon and missing transverse energy from the decay of a W boson from the top quark decay, and two, three, or four jets, with one or two of the jets identified as originating from a b hadron decay. The selected events are mostly backgrounds such as W+jets and t{bar t} events, which we separate from the expected signals using three multivariate analysis techniques: boosted decision trees, Bayesian neural networks, and matrix element calculations. A binned likelihood fit of the signal cross section plus background to the data from the combination of the results from the three analysis methods gives a cross …
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
First study of the radiation-amplitude zero in W gamma production and limits on anomalous WW gamma couplings at s**(1/2) = 1.96- TeV (open access)

First study of the radiation-amplitude zero in W gamma production and limits on anomalous WW gamma couplings at s**(1/2) = 1.96- TeV

None
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the ratio of the p anti-p ---> W+c-jet cross section to the inclusive p anti-p ---> W+jets cross section (open access)

Measurement of the ratio of the p anti-p ---> W+c-jet cross section to the inclusive p anti-p ---> W+jets cross section

None
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV

We measure the t{bar t} production cross section in p{bar p} collisions at {radical}s = 1.96 TeV in the lepton+jets channel. Two complementary methods discriminate between signal and background, b-tagging and a kinematic likelihood discriminant. Based on 0.9 fb{sup -1} of data collected by the D0 detector at the Fermilab Tevatron Collider, we measure {sigma}{sub t{bar t}} = 7.62 {+-} 0.85 pb, assuming the current world average m{sub t} = 172.6 GeV. We compare our cross section measurement with theory predictions to determine a value for the top quark mass of 170 {+-} 7 GeV.
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for h(f) ---> gamma gamma with the D0 detector at s**(1/2) = 1.96-TeV (open access)

Search for h(f) ---> gamma gamma with the D0 detector at s**(1/2) = 1.96-TeV

None
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for large extra dimensions in the mono-photon final state at s**(1/2) = 1.96-TeV (open access)

Search for large extra dimensions in the mono-photon final state at s**(1/2) = 1.96-TeV

The authors report on a search for large extra dimensions in a data sample of approximately 1 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV. They investigate Kaluza-Klein graviton production with a photon and missing transverse energy in the final state. At the 95% C.L. they set limits on the fundamental mass scale M{sub D} from 884 GeV to 778 GeV for 2 to 8 extra dimensions.
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for scalar top quarks in the acoplanar charm jets and missing transverse energy final state in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for scalar top quarks in the acoplanar charm jets and missing transverse energy final state in p anti-p collisions at s**(1/2) = 1.96-TeV

None
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for W-prime Boson Resonances Decaying to a Top Quark and a Bottom Quark (open access)

Search for W-prime Boson Resonances Decaying to a Top Quark and a Bottom Quark

We search for the production of a heavy W{prime} gauge boson that decays to third generation quarks in 0.9 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the D0 detector at the Fermilab Tevatron collider. We find no significant excess in the final-state invariant mass distribution and set upper limits on the production cross section times branching fraction. For a left-handed W{prime} boson with SM couplings, we set a lower mass limit of 731 GeV. For right-handed W{prime} bosons, we set lower mass limits of 739 GeV if the W{prime} boson decays to both leptons and quarks and 768 GeV if the W{prime} boson decays only to quarks. We also set limits on the coupling of the W{prime} boson to fermions as a function of its mass.
Date: March 1, 2008
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the K+ --> pi+ nu nu branching ratio (open access)

Measurement of the K+ --> pi+ nu nu branching ratio

Experiment E949 at Brookhaven National Laboratory studied the rare decay K{sup +}-->pi{sup +} nu{ovr {nu}} and other processes with an exposure of 1.77 x 10{sup 12} k{sup +}'s. The data were analyzed using a blind analysis technique yielding one candidate event with an estimated background of 0.30 {+-} 0.03 events. Combining this result with the observation of two candidate events by the predecessor experiment E787 gave the branching ratio B(K{sup +}-->pi{sup +} nu{ovr {nu}}) = (1.47{sub -0.89}{sup +1.30}) x 10{sup -10}, consistent with the standard model prediction of (0.74 {+-} 0.20) x 10{sup -10}. This is a more detailed report of results previously published [V.V. Anisimovsky et al., Phys. Rev. Lett. 93, 031801 (2004)].
Date: March 1, 2008
Creator: Adler, S.; Anisimovsky, V. V.; Aoki, M.; Ardebili, M.; Artamonov, A. V.; Atiya, M. et al.
Object Type: Article
System: The UNT Digital Library
First Observation of Coherent pi0 Production in Neutrino Nucleus Interactions with E(nu) < 2 GeV (open access)

First Observation of Coherent pi0 Production in Neutrino Nucleus Interactions with E(nu) < 2 GeV

The MiniBooNE experiment at Fermilab has amassed the largest sample to date of {pi}{sup 0}s produced in neutral current (NC) neutrino-nucleus interactions at low energy. This paper reports a measurement of the momentum distribution of {pi}{sup 0}s produced in mineral oil (CH{sub 2}) and the first observation of coherent {pi}{sup 0} production below 2 GeV. In the forward direction, the yield of events observed above the expectation for resonant production is attributed primarily to coherent production off carbon, but may also include a small contribution from diffractive production on hydrogen. Integrated over the MiniBooNE neutrino flux, the sum of the NC coherent and diffractive modes is found to be (19.5 {+-} 1.1 (stat) {+-} 2.5 (sys))% of all exclusive NC {pi}{sup 0} production at MiniBooNE. These measurements are of immediate utility because they quantify an important background to MiniBooNE's search for {nu}{sub {mu}} {yields} {nu}{sub e} oscillations.
Date: March 1, 2008
Creator: Aguilar-Arevalo, A. A.; Anderson, C. E.; Brice, S. J.; Brown, B. C.; Bugel, L.; Cao, J. et al.
Object Type: Article
System: The UNT Digital Library
Differentiating neutrino models on the basis of $\theta_{13}$ and lepton flavor violation (open access)

Differentiating neutrino models on the basis of $\theta_{13}$ and lepton flavor violation

The authors show how models of neutrino masses and mixings can be differentiated on the basis of their predictions for {theta}{sub 13} and lepton flavor violation in radiative charged lepton decays and {mu} - e conversion. They illustrate the lepton flavor violation results for five predictive SO(10) SUSY GUT models and point out the relative importance of their heavy right-handed neutrino mass spectra and {theta}{sub 13} predictions.
Date: March 1, 2008
Creator: Albright, Carl H.
Object Type: Article
System: The UNT Digital Library
Observation of Polarized Positrons from an Undulator-Based Source (open access)

Observation of Polarized Positrons from an Undulator-Based Source

An experiment (E166) at the Stanford Linear Accelerator Center (SLAC) has demonstrated a scheme in which a multi-GeV electron beam passed through a helical undulator to generate multi-MeV, circularly polarized photons which were then converted in a thin target to produce positrons (and electrons) with longitudinal polarization above 80% at 6 MeV. The results are in agreement with Geant4 simulations that include the dominant polarization-dependent interactions of electrons, positrons and photons in matter.
Date: March 6, 2008
Creator: Alexander, G; Barley, J.; Batygin, Y.; Berridge, S.; Bharadwaj, V.; Bower, G. et al.
Object Type: Article
System: The UNT Digital Library
Environmental Exemptions for the Navy’s Mid-Frequency Active Sonar Training Program (open access)

Environmental Exemptions for the Navy’s Mid-Frequency Active Sonar Training Program

The report discusses the laws such as MMPA,ESA,NEPA and CZMA related to marine mammals,Environment and Coastal zone.It also reviews the litigation surrounding the Navy's compliance with these laws in the context of mid frequency active sonar for training purposes of California's coast.
Date: March 4, 2008
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 10, Ed. 1 Thursday, March 6, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 10, Ed. 1 Thursday, March 6, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 6, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 11, Ed. 1 Thursday, March 13, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 11, Ed. 1 Thursday, March 13, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 13, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 12, Ed. 1 Thursday, March 20, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 12, Ed. 1 Thursday, March 20, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 20, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 13, Ed. 1 Thursday, March 27, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 13, Ed. 1 Thursday, March 27, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: March 27, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Results of the 2007 B100 Quality Survey (open access)

Results of the 2007 B100 Quality Survey

In a 2007 analysis of samples from 52% of U.S. biodiesel (B100) producers, 90% met ASTM and other specifications for critical engine performance properties and for elements that harm emission controls.
Date: March 1, 2008
Creator: Alleman, T. L. & McCormick, R. L.
Object Type: Report
System: The UNT Digital Library
Mechanical considerations and design skills. (open access)

Mechanical considerations and design skills.

The purpose of the report is to provide experienced-based insights into design processes that will benefit designers beginning their employment at Sandia National Laboratories or those assuming new design responsibilities. The main purpose of this document is to provide engineers with the practical aspects of system design. The material discussed here may not be new to some readers, but some of it was to me. Transforming an idea to a design to solve a problem is a skill, and skills are similar to history lessons. We gain these skills from experience, and many of us have not been fortunate enough to grow in an environment that provided the skills that we now need. I was fortunate to grow up on a farm where we had to learn how to maintain and operate several different kinds of engines and machines. If you are like me, my formal experience is partially based upon the two universities from which I graduated, where few practical applications of the technologies were taught. What was taught was mainly theoretical, and few instructors had practical experience to offer the students. I understand this, as students have their hands full just to learn the theoretical. The practical part …
Date: March 1, 2008
Creator: Alvis, Robert L.
Object Type: Report
System: The UNT Digital Library
Searching for Gluinos at the Tevatron (open access)

Searching for Gluinos at the Tevatron

This letter describes how to perform model-independent searches for new pair-produced color octet particles that each subsequently decay into two jets plus missing energy at the Tevatron. Current searches are not sensitive to all regions of parameter space because they employ CMSSM-motivated cuts. Optimizing the H{sub T} and E{sub T} cuts expands the sensitivity of searches for all kinematically allowed decays.
Date: March 14, 2008
Creator: Alwall, Johan; Le, My-Phuong; Lisanti, Mariangela; Wacker, Jay G. & /SLAC /Stanford U., Phys. Dept.
Object Type: Article
System: The UNT Digital Library