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in creator/contributor: "Zghiche, A."

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Charm Meson Spectroscopy at BaBar and CLEO-C

In this mini-review we report on the most recent progress in charm meson spectroscopy. We discuss the precision measurements performed by the BABAR and CLEO-c experiments in the non strange charm meson part and we present the newly discovered strange charmed meson excited states.

Date: October 16, 2007

Creator: Zghiche, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Hadronic B Decays at BaBar

By means of hadronic B decays, the BABAR experiment aims to constrain the CKM matrix performing CP parameter measurements. It also seeks to test QCD factorization predictions and other models for B structure and decay mechanisms. We will present some of the on-going CP related analyses in the first section, while the second section will be dedicated to report on the conducted investigations on subjects as diverse as probing the gluon component in the B meson wave function, new physics and final… more

Date: April 18, 2007

Creator: Zghiche, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent developments in laser-driven polarized sources

Recent progress in the performance of laser-driven sources of polarized hydrogen and deuterium is described. The current status of the prototype source, I = 2.5 {times} 10{sup 17}s{sup {minus}1}, polarization = 0.29 (including atomic fraction), is comparable to classical Stern-Gerlach sources. A scheme to improve source performance by approximately an order of magnitude, using a combination of optical-pumping spin-exchange and RF transitions, is outlined. 8 refs., 2 figs., 1 tab.

Date: January 1, 1990

Creator: Young, L.; Coulter, K. P.; Holt, R. J.; Kinney, E. R.; Kowalczyk, R. S.; Potterveld, D. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High field optical-pumping spin-exchange polarized deuterium source

Recent progress in the performance of laser-driven source of polarized deuterium is described. Optical pumping of potassium atoms followed by spin exchange scattering with deuterium atoms in a high magnetic field and RF transitions in a medium field was found to produce an intense, highly spin-polarized beam of deuterium atoms. In particular, the atomic polarization of deuterium was determined to be 73{plus_minus}3% at an intensity of 2.1 {times} 10{sup 17} Atomsis. The RF transition efficiency… more

Date: December 31, 1991

Creator: Zghiche, A.; Coulter, K. P.; Holt, R. J.; Kinney, E. R.; Kowalczyk, R. S.; Potterveld, D. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High field optical-pumping spin-exchange polarized deuterium source

Recent progress in the performance of laser-driven source of polarized deuterium is described. Optical pumping of potassium atoms followed by spin exchange scattering with deuterium atoms in a high magnetic field and RF transitions in a medium field was found to produce an intense, highly spin-polarized beam of deuterium atoms. In particular, the atomic polarization of deuterium was determined to be 73{plus minus}3% at an intensity of 2.1 {times} 10{sup 17} Atomsis. The RF transition efficiency… more

Date: January 1, 1991

Creator: Zghiche, A.; Coulter, K. P.; Holt, R. J.; Kinney, E. R.; Kowalczyk, R. S.; Potterveld, D. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Branching Fraction for B0 -> pi- l+ nu and Determination of |Vub| in Upsilon(4S) -> B0 B0bar Events Tagged by B0bar -> D(*)+ l- nubar

We report preliminary results from a study of the charmless exclusive semileptonic decay B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu} based on the data collected at the {Upsilon}(4S) resonance using the BABAR detector at SLAC. The analysis uses events in which the signal B meson recoils against a B meson that has been reconstructed in a semileptonic decay {bar B}{sup 0} {yields} D{sup (*)+}{ell}{sup -}{bar {nu}}. We extract the total branching fraction {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}… more

Date: June 29, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of the B+- --> rho+- pi0 Branching Fraction and Direct CP Asymmetry

An improved measurement of the process B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0} is presented. The data sample of 211 fb{sup -1} comprises 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The yield and CP asymmetry are calculated using an extended maximum likelihood fitting method. The branching fraction and asymmetry are found to be {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}) = [10.0 {+-} 1.4 (Sta… more

Date: June 29, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of the B0-bar Lifetime and the B0B0-bar Oscillation Frequency Using Partially Reconstructed B0-bar to D*+ l- nu-bar Decays

The authors present a simultaneous measurement of the {bar B}{sup 0} lifetime {tau}{sub B{sup 0}} and B{sup 0}{bar B}{sup 0} oscillation frequency {Delta}m{sub d}. We use a sample of about 50,000 partially reconstructed {bar B}{sup 0} {yields} D*{sup +}{ell}{sup -}{bar {nu}}{sub {ell}} decays identified with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring at SLAC. The flavor of the other B meson in the event is determined from the charge of another high-momentum lepton.

Date: July 27, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A Study of $e^+e^-\to p\bar{p}$ Using Initial StateRadiation with BaBar

The e{sup +}e{sup -} {yields} p{bar p} cross-section is determined over a range of p{bar p} masses, from threshold to 4.5 GeV/c{sup 2}, by studying the e{sup +}e{sup -} {yields} p{bar p}{gamma} process. The data set corresponds to an integrated luminosity of 232 fb{sup -1}, collected with the BABAR detector at the PEP-II storage ring, at an e{sup +}e{sup -} center-of-mass energy of 10.6 GeV. The mass dependence of the ratio of electric and magnetic form factors, |G{sub E}/G{sub M}|, is measured… more

Date: December 13, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for the Rare Decay B0bar -> D*0 gamma

We report on a search for the rare decay {bar B}{sup 0} {yields} D*{sup 0}{gamma}, which in the standard model is dominated by W-exchange. The analysis is based on a data sample comprising 87.8 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. No significant signal is observed, and an upper limit on the branching fraction of 2.5 x 10{sup -5} at the 90% confidence level is obtained.

Date: June 30, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for b->u Transitions inB- -> D0 K- and B- -> D*0 K-

The authors search for B{sup -} {yields} {tilde D}{sup 0}K{sup -} and B{sup -} {yields} {tilde D}*{sup 0}K{sup -}, with {tilde D}*{sup 0} {yields} {tilde D}{sup 0}{pi}{sup 0} or {tilde D}*{sup 0} {yields} {tilde D}{sup 0}{gamma}, and {tilde D}{sup 0} {yields} K{sup +}{pi}{sup -} (and charge conjugates). These final states can be reached through the b {yields} c transition B{sup -} {yields} D{sup (*)0}K{sup -} followed by the doubly CKM-suppressed D{sup 0} {yields} K{sup +}{pi}{sup -}, or the b … more

Date: May 27, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of the B0 to D* D_s*+ and D_s+ to phi pi+ Branching Fractions

The authors present measurements of the branching fractions {Beta}(B{sup 0} {yields} D*{sup -}D*{sub s}{sup +}) and {Beta}(D{sub s}{sup +} {yields} {phi}{pi}{sup +}), based on 123 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} B factory. A partial reconstruction technique is used to measure {Beta}(B{sup 0} {yields} D*{sup -}D*{sub s}{sup +}) and the decay chain is fully reconstructed to measure the branching fr… more

Date: June 22, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for the Rare Decays B+ to D(*)+K0s

The authors report on the search for the rare decays B{sup +} {yields} D{sup (*)+} K{sub s}{sup 0} in approximately 226 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEp-II asymmetric-energy B factory at SLAC. They do not observe any significant signal and they set 90% confidence level upper limits on the branching fractions, {Beta}(B{sup +} {yields} D{sup +}K{sup 0}) < 0.5 x 10{sup -5} and {Beta}(B{sup +} {yields} D*{sup +} K{sup 0}) < 0.9 x 10{s… more

Date: June 2, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of Branching Fraction and CP-Violating Asymmetry for B-> omega K0s

The authors present a preliminary measurement of the branching fraction and CP-violating parameters S and C for the decay B{sup 0} {yields} {omega}K{sub S}{sup 0}. The data sample corresponds to 232 x 10{sup 6} B{bar B} pairs produced from e{sup +}e{sup -} annihilation at the {Upsilon}(4S) resonance. They measure {Beta}(B{sup 0} {yields} {omega}K{sup 0}) = (5.9 {+-} 1.0 {+-} 0.4) x 10{sup -6}, S = 0.50{sub -0.38}{sup +0.34} {+-} 0.02 and C = -0.56{sub -0.27}{sup +0.29} {+-} 0.03.

Date: June 8, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of Time-Dependent CP Asymmetries in B0 to D(*)D Decays

The authors present a first measurement of CP asymmetries in neutral B decays to D{sup +}D{sup -}, and updated CP asymmetry measurements in decays to D*{sup +}D{sup -} and D*{sup -}D{sup +}. They use fully-reconstructed decays collected in a data sample of (232 {+-} 3) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events in the BABAR detector at the PEp-II asymmetric-energy B Factory at SLAC. they determine the time-dependent asymmetry parameters to be S{sub D*{sup +}D{sup -}} = -0.54 {+-} 0.35 {… more

Date: June 24, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of gamma in B-+ to D() K-+ and B-+ to D K-+ Decays with a Dalitz Analysis of D to Ks pi- pi+

We present a measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} with a Dalitz plot analysis of neutral D-meson decays to the K{sub S}{sup 0} {pi}{sup -}{pi}{sup +} final state from B{sup {-+}} {yields} D{sup (*)}K{sup {-+}} and B{sup {-+}} {yields} DK*{sup {-+}} decays, using a sample of 227 million B{bar B} pairs collected by the BABAR detector. We measure {gamma} = (67 {+-} 28 {+-} 13 {+-} 11){sup o}, where the first error is statistical, the second is the experimental sy… more

Date: August 4, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for Lepton-Flavor and Lepton-Number Violation in the Decay tau to lhh'

A search for lepton-flavor and lepton-number violation in the decay of the tau lepton into one charged lepton and two charged hadrons is performed using 221.4 fb{sup -1} of data collected at an e{sup +}e{sup -} center-of-mass energy of 10.58 GeV with the BABAR detector at the PEP-II storage ring. In all 14 decay modes considered, the observed data are compatible with background expectations, and upper limits are set in the range {Beta}({tau} {yields} {ell}hh') < (0.7-4.8) x 10{sup -7} at 90%… more

Date: June 29, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of Time-Dependent CP-Violating Asymmetries in B^0 Meson Decays to eta' K^0_L

The authors present a preliminary measurement of CP-violating parameters S and C from fits of the time-dependence of B{sup 0} meson decays to {eta}'K{sub L}{sup 0}. The data were recorded with the BABAR detector at PEP-II and correspond to 232 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation through the {Upsilon}(4S) resonance. By fitting the time-dependent CP asymmetry of the reconstructed B{sup 0} {yields} {eta}'K{sub L}{sup 0} events, they find S = 0.60 {+-} 0.31 {+-} 0.0… more

Date: August 23, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of the Time-Dependent CP-Violating Asymmetry in $B^0 \to K^{0}_s\pi^0\gamma$ Decays

We present a measurement of the time-dependent CP-violating asymmetry in B{sup 0} {yields} K*{sup 0}{gamma} decays with K*{sup 0} {yields} K{sub S}{sup 0}{pi}{sup 0} based on 232 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. In a sample containing 157 {+-} 16 signal decays, we measure S{sub K*{sup 0}{gamma}} = -0.21 {+-} 0.40 {+-} 0.05 and C{sub K*{sup 0}{gamma}} = -0.40 {+-} 0.23 {+-} 0.03, wh… more

Date: July 12, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for W-exchange decays B0 -> Ds()- Ds()+

The authors report a search for the decays B{sup 0} {yields} D{sub s}{sup -}D{sub s}{sup +}, B{sup 0} {yields} D*{sub s}{sup -}D{sub s}{sup +} and B{sup 0} {yields} D*{sub s}{sup -}D*{sub s}{sup +} in a sample of 232 million {Upsilon}(4S) decays to B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They find no significant signal and set upper bounds for the branching fractions: {Beta}(B{sup 0} {yields} D{sub s}{sup -}D{sub s}{sup +})… more

Date: October 26, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Search for B- -> Ds+(*)- Phi

We report on searches for B{sup -} {yields} D{sub S}{sup -}{phi} and B{sup -} {yields} D*{sub S}{sup -}{phi}. In the context of the Standard Model the branching fractions for these decays are expected to be highly suppressed, since they proceed through annihilation of the b and {bar u} quarks in the B{sup -} meson. Our results are based on 234 million {Upsilon}(42) {yields} B{bar B} decays collected with the BABAR detector at SLAC. We find no evidence for these decays, and we set 90% confidence… more

Date: July 6, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measurement of the $B^+\rightarrow p \bar{p} K^{+}$ Branching Fraction and Study of the Decay Dynamics

With a sample of 232 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector, we study the decay B{sup +} {yields} p{bar p}K{sup +} excluding charmonium decays to p{bar p}. We measure a branching fraction {Beta}(B{sup +} {yields} p{bar p}K{sup +}) = (6.7 {+-} 0.5 {+-} 0.4) x 10{sup -6}. An enhancement at low p{bar p} mass is observed and the Dalitz plot asymmetry suggests dominance of the penguin amplitude in this B decay. We search for a pentaquark candidate {Theta… more

Date: July 6, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of Branching Fractions and Mass Spectra of B to K pi pi gamma

The authors present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B {yields} K{pi}{pi}{gamma} in the range m{sub K{pi}{pi}} < 1.8 GeV/c{sup 2}. They reconstruct four final states: K{sup +}{pi}{sup -}{pi}{sup +}{gamma}, K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}, K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}{gamma}, and K{sub S}{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}, where K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}. Using 232 million e{su… more

Date: July 12, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of CP Asymmetries for the Decays B^+/- --> D^0_CP K*^+/-

Using a sample of 232 million {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II B Factory in 1999-2004, they study B{sup -} {yields} K{sup 0}K*(892){sup -} decays where K*{sup -} {yields} K{sub S}{sup 0} {pi}{sup -} and D{sup 0} {yields} K{sup -}{pi}{sup +}, K{sup -}{pi}{sup +}{pi}{sup 0}, K{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -} (non-CP final states); K{sup +}K{sup -}, {pi}{sup +}{pi}{sup -} (CP+ eigenstates); K{sub S}{sup 0}{pi}{sup 0}, K{sub S}{sup 0}{ph… more

Date: July 6, 2005

Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department