Evaluating GC/MS Performance (open access)

Evaluating GC/MS Performance

Evaluating the chemical background in the GC/MS system (system background) and solvent purity. This procedure will allow the analyst to verify that the GC/MS is free of chemical interferences or contamination and verify the solvent being utilized is free of interferences - Conduct a GC/MS analysis without injecting a solvent (system background) and Conduct a GC/MS analysis inject 1uL of CH2Cl2 solvent (Solvent background). GC conditions: (1) Injector Temperature (C): Injector Temperature is typically set at 250; (2) Transferline Temperature (C) - The Transferline Temperature is typically set at 280 C; (3) Constant flow (Sec./cm2) - This value, in seconds per cubic cm. Typically, set at 32; (4) Splitless mode (Sec.) - This value, in seconds, is the time before the purge valve opens. Typically, set at 45 seconds; (5) Starting Temperature (C): The Starting Temperature value can be set at 40 C; (6) Hold Time 1 (Min.) - Hold Time 1 is the amount of time, in minutes at the Starting Temperature that Ramp 1 Temperature is held. Typically set at 3 minutes; (7) Ramp 1 Rate (C/Min.) - Ramp 1 Rate is the temperature rise per unit time and has a typically value of 8 C per minute …
Date: November 26, 2006
Creator: Alcaraz, A. & Dougan, A.
Object Type: Report
System: The UNT Digital Library
Method to prepare Semtex (open access)

Method to prepare Semtex

This procedure requires the binder and uncoated RDX be prepared in separate steps, see Figure 1: (1) The binder and dye are mixed by agitation with a water-insoluble organic solvent (e.g., toluene), I; (2) The RDX/PETN is agitated thoroughly with water, II; (3) The binder solution I is added to the RDX/water mixture at II with thorough mixing to form a slurry III; (4) In the next step the solvent is distilled off at IV leaving resulting granules; (5) The next step is followed by filtration at V, which may be done by vacuum; (6) The composition is then dried at VI to a dough-like consistency.
Date: November 26, 2006
Creator: Alcaraz, A. & Dougan, A.
Object Type: Report
System: The UNT Digital Library
Assessing the Prospects for Achieving Double-Shell Ignition on the National Ignition Facility Using Vacuum Hohlraums (open access)

Assessing the Prospects for Achieving Double-Shell Ignition on the National Ignition Facility Using Vacuum Hohlraums

The goal of demonstrating ignition on the National Ignition Facility (NIF) has motivated a revisit of double-shell (DS) targets as a complementary path to the cryogenic baseline approach. Expected benefits of DS ignition targets include non-cryogenic deuterium-tritium (DT) fuel preparation, minimal hohlraum-plasma mediated laser backscatter, low threshold ignition temperatures ({approx} 4 keV) for relaxed hohlraum x-ray flux asymmetry tolerances, and minimal (two-) shock timing requirements. On the other hand, DS ignition presents several formidable challenges, encompassing room-temperature containment of high-pressure DT ({approx} 790 atm) in the inner shell, strict concentricity requirements on the two shells (< 3 {micro}m), development of nano-porous (<100 nm) low-density (<100 mg/cc) metallic foams for structural support of the inner shell and hydrodynamic instability mitigation, and effective control of hydrodynamic instabilities on the high-Atwood number interface between the DT fuel and the high-Z inner shell. Recent progress in DS ignition designs and required materials-science advances at the nanoscale are described herein. Two new ignition designs that use rugby-shaped vacuum hohlraums are presented which utilize either 1 MJ or 2 MJ of laser energy at 3{omega}. The capability of the NIF to generate the requested reverse-ramp pulse shape for DS ignition is expected to be comparable to …
Date: October 26, 2006
Creator: Amendt, P.; Cerjan, C.; Hamza, A.; Hinkel, D.; Milovich, J. L. & Robey, H. F.
Object Type: Article
System: The UNT Digital Library
Determination of the Form Factors for the Decay B0 -> D*-l+nu_l and of the CKM Matrix Element |Vcb| (open access)

Determination of the Form Factors for the Decay B0 -> D*-l+nu_l and of the CKM Matrix Element |Vcb|

The authors present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub cb}| and of the parameters {rho}{sup 2}, R{sub 1}, and R{sub 2}, which fully characterize the form factors of the B{sup 0} {yields} D*{sup -}{ell}{sup +}{nu}{sub {ell}} decay in the framework of HQET, based on a sample of about 52,800 B{sup 0} {yields} D*{sup -}{ell}{sup +}{nu}{sub {ell}} decays recorded by the BABAR detector. The kinematical information of the fully reconstructed decay is used to extract the following values for the parameters (where the first errors are statistical and the second systematic): {rho}{sup 2} = 1.156 {+-} 0.094 {+-} 0.028, R{sub 1} = 1.329 {+-} 0.131 {+-} 0.044, R{sub 2} = 0.859 {+-} 0.077 {+-} 0.022, F(1)|V{sub cb}| = (35.03 {+-} 0.39 {+-} 1.15) x 10{sup -3}. By combining these measurements with the previous BABAR measurements of the form factors which employs a different technique on a partial sample of the data, they improve the statistical accuracy of the measurement, obtaining: {rho}{sup 2} = 1.179 {+-} 0.048 {+-} 0.028, R{sub 1} = 1.417 {+-} 0.061 {+-} 0.044, R{sub 2}, = 0.836 {+-} 0.037 {+-} 0.022, and F(1)|V{sub cb}| = (34.68 {+-} 0.32 {+-} 1.15) x 10{sup -3}. Using the …
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Improved Measurements of the Branching Fractions for B0 into pi+pi- and B0 into K+pi-, and a Search for B0 into K+K- (open access)

Improved Measurements of the Branching Fractions for B0 into pi+pi- and B0 into K+pi-, and a Search for B0 into K+K-

The authors present measurements of the branching fractions for the charmless two-body decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -} and B{sup 0} {yields} K{sup +}{pi}{sup -}, and a search for the decay B{sup 0} {yields} K{sup +}K{sup -}. They include the effects of final-state radiation from the daughter mesons for the first time, and quote branching fractions for the inclusive processes B{sup 0} {yields} h{sup +}h'{sup -}n{gamma}, where h and h' are pion or kaons. The maximum value of the sum of the energies of the n undetected photons, E{sub {gamma}}{sup max}, is mode-dependent. Using a data sample of approximately 227 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of Branching Fractions and Charge Asymmetries in B Decays to an eta Meson and a K* Meson (open access)

Measurement of Branching Fractions and Charge Asymmetries in B Decays to an eta Meson and a K* Meson

The authors present measurements of branching fractions and charge asymmetries for the decays B {yields} {eta}K*, where K8 indicates a spin 0, 1, or 2 K {pi} system. The data sample corresponds to 344 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. They measure the branching fractions (in units of 10{sup -6}): {Beta}(B{sup 0} {yields} {eta}K*{sup 0}(892)) = 16.5 {+-} 1.1 {+-} 0.8, {Beta}(B{sup +} {yields} {eta}K*{sup +}(892)) = 18.9 {+-} 1.8 {+-} 1.3, {Beta}(B{sup 0} {yields} {eta}(K{pi})*{sub 0}{sup 0}) = 11.0 {+-} 1.6 {+-} 1.5, {Beta}(B{sup +} {yields} {eta}(K{pi}){sub 0}*{sup +}) = 18.2 {+-} 2.6 {+-} 2.6, {Beta}(B{sup 0} {yields} {eta}K*{sub 2}{sup 0}(1430)) = 9.6 {+-} 1.8 {+-} 1.1, and {Beta}(B{sup +} {yields} {eta}K*{sub 2}{sup +}(1430)) = 9.1 {+-} 2.7 {+-} 1.4. They also determine the charge asymmetries for all decay modes.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of CP Asymmetries and Branching Fractions in B to pi pi and B to K pi Decays. (open access)

Measurement of CP Asymmetries and Branching Fractions in B to pi pi and B to K pi Decays.

The authors present preliminary measurements of the Cp asymmetries and branching fractions for B {yields} {pi}{pi} and B {yields} K{pi} decays. A total of 347 million B{bar B} events collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC are used for these results.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of CP-Violating Asymmetries in B0 to (rho pi)0 Using a Time-Dependent Dalitz Plot Analysis (open access)

Measurement of CP-Violating Asymmetries in B0 to (rho pi)0 Using a Time-Dependent Dalitz Plot Analysis

We report a measurement of CP-violating asymmetries in B{sup 0} {yields} ({rho}{pi}){sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 347 million {Upsilon}(4S) {yields} B{bar B} decays, collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure 26 coefficients of the bilinear form factor terms occurring in the time-dependent decay rate of the B{sup 0} meson and derive the physically relevant quantities from these coefficients. In particular we find a three standard deviation evidence of direct CP-violation in the B{sup 0} {yields} {rho}{sup {+-}}{pi}{sup {-+}} decays, with systematic uncertainties included. We also achieve a constraint of the angle {alpha} of the Unitarity Triangle. All results presented are preliminary.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of the Branching Fraction and Photon Energy Moments of B to Xs gamma and A_cp (B to X_{s+d} gamma) (open access)

Measurement of the Branching Fraction and Photon Energy Moments of B to Xs gamma and A_cp (B to X_{s+d} gamma)

The photon spectrum in B {yields} X{sub s}{gamma} decay, where X{sub s} is any strange hadronic state, is studied using a data sample of 88.5 x 10{sup 6} e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR experiment at SLAC. The partial branching fraction, {Delta}{Beta}(B {yields} X{sub s}{gamma}) = (3.67 {+-} 0.29(stat.) {+-} 0.34(sys.) {+-} 0.29(model)) x 10{sup -4}, the first moment <E{sub {gamma}}> = 2.288 {+-} 0.025 {+-} 0.017 {+-} 0.015 GeV and the second moment <E{sub {gamma}}{sup 2}> = 0.0328 {+-} 0.0040 {+-} 0.0023 {+-} 0.0036 GeV{sup 2} are measured for the photon energy range 1.9 GeV < E{sub {gamma}} < 2.7 GeV. They are also measured for narrower E{sub {gamma}} ranges. The moments are then fit to recent theoretical calculations to extract the Heavy Quark Expansion parameters, m{sub b} and {mu}{sub {pi}}{sup 2}, and to extrapolate the partial branching fraction to E{sub {gamma}} > 1.6 GeV. In addition, the direct CP asymmetry A{sub CP}(B {yields} X{sub s+d{gamma}}) is measured to be -0.110 {+-} 0.115(stat.) {+-} 0.017(sys.).
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of the Branching Fraction and Time-Dependent CP Asymmetry in the Decay B0 to D*+D*-Ks (open access)

Measurement of the Branching Fraction and Time-Dependent CP Asymmetry in the Decay B0 to D*+D*-Ks

The authors study the decay B{sup 0} {yields} D*{sup +}D*{sup -} K{sub S}{sup 0} using (230 {+-} 2) x 10{sup 6} B{bar B} pairs collected by the BABAR detector at the PEP-II B factory. They measure a branching fraction {Beta}(B{sup 0} {yields} D*{sup +}D*{sup -} K{sub S}{sup 0}) = (4.4 {+-} 0.4 {+-} 0.7) x 10{sup -3} and find evidence for the decay B{sup 0} {yields} D*{sup -} D{sub s1}{sup +}(2536) with a statistical significance of 4.6 {sigma}. A time-dependent CP asymmetry analysis is also performed to study the possible resonant contributions to B{sup 0} {yields} D*{sup +}D*{sup -} K{sub S}{sup 0} and the sign of cos2{beta}. Their measurement indicates that there is a sizable resonant contribution to the decay B{sup 0} {yields} D*{sup +} D*{sup -} K{sub S}{sup 0} from a unknown D{sub s1}{sup +} state with large width, and that cos2{beta} is positive at the 94% confidence level under certain theoretical assumptions.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of the CP-violating Asymmetries in B0->K0Spi0 and of the Branching Fraction of B0->K0pi0 (open access)

Measurement of the CP-violating Asymmetries in B0->K0Spi0 and of the Branching Fraction of B0->K0pi0

The authors present a measurement of the time-dependent CP-violating asymmetries in B{sup 0} {yields} K{sub S}{sup 0}{pi}{sup 0} decays based on 348 million {Upsilon}(4S) {yields} B{bar B} events collected by the BABAR experiment at the PEP-II asymmetric-energy B Factory at SLAC. They measure the direct Cp-violating asymmetry C{sub K{sub S}{sup 0}{pi}{sup 0}} = 0.20 {+-} 0.16 {+-} 0.03 and the CP-violating asymmetry in the interference between mixing and decay S{sub K{sub S}{sup 0}{pi}{sup 0}} = 0.33 {+-} 0.26 {+-} 0.04 where the first error is statistical and the second systematic. On the same sample, they measure the decay branching fraction, obtaining {Beta}(B{sup 0} {yields} K{sub S}{sup 0}{pi}{sup 0}) = (10.5 {+-} 0.7 {+-} 0.5) x 10{sup -6}. All results presented here are preliminary.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of the q2 Dependence of the Hadronic Form Factor in D0 to K- e+ nu_e Decays (open access)

Measurement of the q2 Dependence of the Hadronic Form Factor in D0 to K- e+ nu_e Decays

A preliminary measurement of the q{sup 2} dependence of the D{sup 0} {yields} K{sup -}e{sup +}{nu}{sub e} decay rate is presented. This rate is proportional to the hadronic form factor squared, specified by a single parameter. This is either the mass in the simple pole ansatz m{sub pole} = (1.854 {+-} 0.016 {+-} 0.020) GeV/c{sup 2} or the scale in the modified pole ansatz {alpha}{sub pole} = 0.43 {+-} 0.03 {+-} 0.04. The first error refers to the statistical, the second to the systematic uncertainty.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurement of the Relative Branching Fractions for B^- to D/D^{*}/D^{**}(D^{(*)}\pi) \ell^- \bar{\nu}_{\ell} with a Large Sample of Tagged B Mesons (open access)

Measurement of the Relative Branching Fractions for B^- to D/D^{*}/D^{**}(D^{(*)}\pi) \ell^- \bar{\nu}_{\ell} with a Large Sample of Tagged B Mesons

We present a study of B semileptonic decays into charm final states based on 211.7 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. Using a novel technique based on the simultaneous fit of a set of variables reconstructed on the recoil of a B tagged in an hadronic decay mode, we measure the relative branching fractions {Lambda}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = 0.611 {+-} 0.022 (stat.) {+-} 0.027 (syst.) and {Lambda}(B{sup -} {yields} D**{sup 0})(D{sup (*)}{pi}){ell}{sup -}{bar {nu}}{sub {ell}}/{Lambda}(B{sup -} {yields} DX{ell}{sup -}{bar {nu}}{sub {ell}}) = 0.173 {+-} 0.017 (stat.) {+-} 0.021 (syst.).
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Measurements of Branching Fractions, Polarizations, and Direct CP-Violation Asymmetries in B to rho K* and B to f0(980) K* Decays (open access)

Measurements of Branching Fractions, Polarizations, and Direct CP-Violation Asymmetries in B to rho K* and B to f0(980) K* Decays

The authors report searches for B-meson decays to the charmless final states {rho}K* and f{sub 0}(980)K* with a sample of 232 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Observation of B to eta' K* and Evidence for B+ to eta' rho+ (open access)

Observation of B to eta' K* and Evidence for B+ to eta' rho+

The authors presented an observation of B {yields} {eta}{prime}K*. The data sample corresponds to 232 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. They measure the branching fractions (in units of 10{sup -6}) {Beta}(B{sup 0} {yields} {eta}{prime}K*{sup 0}) = 3.8 {+-} 1.1 {+-} 0.5 and {Beta}(B{sup +} {yields} {eta}{prime}K*{sup +}) = 4.9{sub -1.7}{sup +1.9} {+-} 0.8, where the first error is statistical and the second systematic. A simultaneous fit results in the observation of B {yields} {eta}{prime}K* with {Beta}(B {yields} {eta}{prime}K*) = 4.1{sub -0.9}{sup +1.0} {+-} 0.5. They also search for B {yields} {eta}{prime}{rho} and {eta}{prime} f{sub 0}(980)(f{sub 0} {yields} {pi}{sup +}{pi}{sup -}) with results and 90% confidence level upper limits {Beta}(B{sup +} {yields} {eta}{prime}{rho}{sup +}) = 8.7{sub -2.8-1.3}{sup +3.1+2.3} (< 14), {Beta}(B{sup 0} {yields} {eta}{prime}{rho}{sup 0}) < 3.7, and {Beta}(B{sup 0} {yields} {eta}{prime} f{sub 0}(980)(f{sub 0} {yields} {pi}{sup +}{pi}{sup -})) < 1.5. Charge asymmetries in the channels with significant yields are consistent with zero.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Search for CPT and Lorentz Violation in B0-B0bar Oscillations with Inclusive Dilepton Events (open access)

Search for CPT and Lorentz Violation in B0-B0bar Oscillations with Inclusive Dilepton Events

We report preliminary results of a search for CPT and Lorentz violation in B{sup 0}-{bar B}{sup 0} oscillations using an inclusive dilepton sample collected by the BABAR experiment at the PEP-II B Factory. Using a sample of 232 million B{bar B} pairs, we search for time-dependent variations in the complex CPT parameter z = z{sub 0} +z{sub 1} cos ({Omega}{cflx t} + {phi}) where {Omega} is the Earth's sidereal frequency and {cflx t} is sidereal time. We measure Imz{sub 0} = (-14.1 {+-} 7.3(stat.) {+-} 2.4(syst.)) x 10{sup -3}, {Delta}{Lambda} x Rez{sub 0} = (-7.2 {+-} 4.1(stat.) {+-} 2.1(syst.)) x 10{sup -3} ps{sup -1}, Im z{sub 1} = (-24.0 {+-} 10.7(stat.) {+-} 5.9(syst.)) x 10{sup -3}, and {Delta}{Lambda} x Re z{sub 1} = (-18.8 {+-} 5.5(stat.) {+-} 4.0(syst.)) x 10{sup -3} ps{sup -1}, where {Delta}{Lambda} is the difference between the decay rates of the neutral B mass eigenstates. The statistical correlation between the measurements of Imz{sub 0} and {Delta}{Lambda} x Rez{sub 0} is 76%; between Imz{sub 1} and {Delta}{Lambda} x Rez{sub 1} it is 79%. These results are used to evaluate expressions involving coefficients for Lorentz and CPT violation in the general Lorentz-violating standard-model extension. In a complementary approach, we …
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Search for D<sup>0</sup> - anti-D<sup>0</sup> Mixing and Branching-Ratio Measurement in the Decay D<sup>0</sup> to K<sup>+</sup> pi<sup>-</sup> pi<sup>0</sup> (open access)

Search for D<sup>0</sup> - anti-D<sup>0</sup> Mixing and Branching-Ratio Measurement in the Decay D<sup>0</sup> to K<sup>+</sup> pi<sup>-</sup> pi<sup>0</sup>

The authors present a search for D{sup 0}-{bar D}{sup 0} mixing using regions of phase space in which the rate of doubly Cabibbo-suppressed decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} relative to Cabibbo-favored decays D{sup 0} {yields} K{sup -} {pi}{sup +}{pi}{sup 0} is reduced. They analyze 230.4 fb{sup -1} of data collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. They present results with and without the assumption of CP conservation. Assuming CP conservation, they measure the time-integrated mixing rate R{sub M} = (0.023{sub -0.014}{sup +0.018}(stat.) {+-} 0.004(syst.))%, and R{sub M} &lt; 0.054% at the 95% confidence level. They find that the data are consistent with no mixing at the 4.5% confidence level. Considering the entire allowed phase space, they measure the branching ratio for D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} relative to D{sup 0} {yields} K{sup -} {pi}{sup +}{pi}{sup 0} to be (0.214 {+-} 0.008(stat.) {+-} 0.008(syst.))%.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Search for D0--anti-D0 Mixing in the Decays D0 --> K+ pi- pi+ pi- (open access)

Search for D0--anti-D0 Mixing in the Decays D0 --> K+ pi- pi+ pi-

We present a search for D{sup 0}-{bar D}{sup 0} mixing in the decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} using 230.4 fb{sup -1} of data collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. Assuming CP conservation, we measure the time-integrated mixing rate R{sub M} = (0.019{sub -0.015}{sup +0.016}(stat.) {+-} 0.002(syst.))%, and R{sub M} &lt; 0.048% at the 95% confidence level. Using a frequentist method, we estimate that the data are consistent with no mixing at the 4.3% confidence level. We present results both with and without the assumption of CP conservation. By combining the value of R{sub M} from this analysis with that obtained from an analysis of the decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}, we find R{sub M} = (0.020{sub -0.010}{sup +0.011})%, where the uncertainty is statistical only. We determine the upper limit R{sub M} &lt; 0.042% at the 95% confidence level, and we find the combined data are consistent with the no-mixing hypothesis at the 2.1% confidence level.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Search for Inclusive Charmless B to K+X and B to K0X Decays (open access)

Search for Inclusive Charmless B to K+X and B to K0X Decays

We present preliminary results from a search for inclusive charmless B {yields} KX decays. These decays occur dominantly via one-loop b {yields} s penguin transitions, and can provide useful information about these processes. Using a sample of 288.5 fb{sup -1} collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} B Factory at SLAC, we search for high-energy kaons recoiling against fully reconstructed B decays. We measure the partial branching fractions for kaons with momentum p*(K) &gt; 2.34 GeV in the B rest frame, and obtain (in units of 10{sup -6}): {Beta}(B {yields} K{sup +}X, p* &gt; 2.34 GeV) = 1.96{sub -34}{sup +37}(stat.){sub -30}{sup +31}(syst.) and {Beta}(B {yields} K{sup 0}X, p* &gt; 2.34 GeV) = 154{sub -48}{sup +55}(stat.){sub -41}{sup +55}(syst.) (&lt; 266 at 90% C.L.).
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Search for the Rare Decay B to pi l+ l- (open access)

Search for the Rare Decay B to pi l+ l-

The authors present results of a search for the rare flavor-changing neutral-current decay B {yields} {pi}{ell}{sup +}{ell}{sup -}, based on a data sample corresponding to 209 fb{sup -1} of integrated luminosity collected with the BABAR detector at the PEP-II B Factory. They reconstruct the four exclusive B decay modes B{sup +} {yields} {pi}{sup +}{ell}{sup +}{ell}{sup -} and B{sup 0} {yields} {pi}{sup 0}{ell}{sup +}{ell}{sup -}, where {ell} is either an e or {mu}. They find no evidence for a signal, and they obtain the upper limit at 90% confidence level on the lepton-flavor-averaged branching fraction to be {Beta}(B{sup +} {yields} {pi}{sup +}{ell}{sup +}{ell}{sup -}) = 2 x {tau}B{sup +}/{tau}B{sup 0} {Beta}(B{sup 0} {yields} {pi}{sup 0}{ell}{sup +}{ell}{sup -}) &lt; 7.9 x 10{sup -8}. The authors also obtain an upper limit at 90% confidence level on the lepton-flavor-violating decay B {yields} {pi}e{mu} of {Beta}(B {yields} {pi}e{mu}) &lt; 9.8 x 10{sup -8}.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Updated Measurement of the CKM Angle alpha Using B0->rho+rho- Decays (open access)

Updated Measurement of the CKM Angle alpha Using B0->rho+rho- Decays

The authors present results from an analysis of B{sup 0} {yields} {rho}{sup +}{rho}{sup -} using 316 fb{sup -1} of {Upsilon}(4S) {yields} B{bar B} decays observed with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. They measure the B{sup 0} {yields} {rho}{sup +}{rho}{sup -} branching fraction, longitudinal polarization fraction f{sub L}, and the CP-violating parameters S{sub long} and C{sub long}: {Beta}(B{sup 0} {yields} {rho}{sup +}{rho}{sup -}) = (23.5 {+-} 2.2(stat) {+-} 4.1(syst)) x 10{sup -6}, f{sub L} = 0.977 {+-} 0.024(stat){sub -0.013}{sup +0.015}(syst), S{sub long} = -0.19 {+-} 0.21(stat){sub -0.07}{sup +0.05}(syst), C{sub long} = -0.07 {+-} 0.15(stat) {+-} 0.06(syst). Using an isospin analysis of B {yields} {rho}{rho} decays they determine the angle {alpha} of the unitarity triangle. One of the two solutions, {alpha} [74,117]{sup o} at 68% CL, is compatible with the standard model. All results presented here are preliminary.
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Xic' Production at BABAR (open access)

Xic' Production at BABAR

Using 232 fb{sup -1} of data collected by the BABAR detector, the {Xi}'{sub c}{sup +} and {Xi}'{sub c}{sup 0} baryons are reconstructed through the decays: {Xi}'{sub c}{sup +} {yields} {Xi}{sub c}{sup +}{gamma} and {Xi}'{sub c}{sup 0} {yields} {Xi}{sub c}{sup 0}{gamma}, where {Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +} and {Xi}{sub c}{sup 0} {yields} {Xi}{sup -} {pi}{sup +}. By measuring the efficiency-corrected yields in different intervals of the center-of-mass momentum, the production rates from B decays and from the continuum are extracted. For production from B decays, the branching fractions are found to be {Beta}(B {yields} {Xi}'{sub c}{sup +}X) x {Beta}({Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +}) = [1.69 {+-} 0.17 (exp.) {+-} 0.10 (model)] x 10{sup -4} and {Beta}(B {yields} {Xi}'{sub c}{sup 0}X) x {Beta} {Xi}{sub c}{sup 0} {yields} {Xi}{sup -} {pi}{sup +} = [0.67 {+-} 0.07 (exp.) {+-} 0.03 (model)] x 10{sup -4}. For production from the continuum the cross-sections are found to be {sigma}(e{sup +}e{sup -} {yields} {Xi}'{sub c}{sup +}X) x {Beta}({Xi}{sub c}{sup +} {yields} {Xi}{sup -} {pi}{sup +}{pi}{sup +}) = 141 {+-} 24 (exp.) {+-} 19 (model) fb and {sigma}(e{sup +}e{sup -} {yields} {Xi}'{sub c}{sup 0}X) x {Beta}({Xi}{sub c}{sup 0} {yields} {Xi}{sup -} {pi}{sup +}) …
Date: September 26, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Non-Destructive Evaluation of Thermal Spray Coating Interface Quality by Eddy Current Method (open access)

Non-Destructive Evaluation of Thermal Spray Coating Interface Quality by Eddy Current Method

Thermal spray coating is usually applied through directing molten or softened particles at very high velocities onto a substrate. An eddy current non-destructive inspection technique is presented here for thermal spray coating interface quality characterization. Several high-velocity-oxy-fuel (HVOF) coated steel plates were produced with different surface preparation conditions before applying the coating, e.g., grit-blasted surface, wire-brush cleaned surface, and a dirty surface. A quad-frequency eddy current probe was used to manually scan over the coating surface to evaluate the bonding quality. Experimental results show that the three surface preparation conditions can be successfully differentiated by looking into the impedance difference observed from the eddy current probe. The measurement is fairly robust and consistent. More specimens are also prepared with variations of process parameters, such as spray angle, stand-off distance, and application of corrosion protective sealant, etc. They are blindly tested to evaluate the reliability of the eddy current system. Quantitative relations between the coating bond strength and the eddy current response are also established with the support of destructive testing. This non-contact, non-destructive, easy to use technique has the potential for evaluating the coating quality immediately after its application so that any defects can be corrected immediately.
Date: May 26, 2006
Creator: B.Mi; Zhao, X. & Bayles, R.
Object Type: Report
System: The UNT Digital Library
A Precision Measurement of the Ds1 (2536)+ Meson Mass and Decay Width (open access)

A Precision Measurement of the Ds1 (2536)+ Meson Mass and Decay Width

The decay width and the mass of the D{sub s1}(2536){sup {+-}} have been measured via the decay channel D{sub s1}{sup {+-}} {yields} D*{sup {+-}}K{sub S}{sup 0} using 232 fb{sup -1} of data collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. The result for the decay width is {Lambda}(D{sub s1}{sup {+-}}) = (1.03 {+-} 0.05 {+-} 0.12) MeV/c{sup 2}, with the first error denoting the statistical uncertainty and the second one the systematic uncertainty. For the mass, a value of m(D{sub s1}{sup {+-}}) = (2534.85 {+-} 0.02 {+-} 0.40) MeV/c{sup 2} has been obtained. The systematic error is dominated by the uncertainty on the D*{sup {+-}} mass. The mass difference between the D{sub s1}{sup {+-}} and D*{sup {+-}} has been measured to be {Delta}m = (524.85 {+-} 0.02 {+-} 0.04) MeV/c{sup 2}.
Date: September 26, 2006
Creator: BABAR Collaboration,
Object Type: Article
System: The UNT Digital Library