Records |
Author |
BABAR Collaboration (del Amo Sanchez, P. et al); Lopez-March, N.; Martinez-Vidal, F.; Milanes, D.A.; Oyanguren, A. |
Title |
Measurement of CP observables in B-+/- -> DCPK +/- decays and constraints on the CKM angle gamma |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
82 |
Issue |
7 |
Pages |
072004 - 20pp |
Keywords |
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Abstract |
Using the entire sample of 467 x 10(6) Y(4S) -> B (B) over bar decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the SLAC National Accelerator Laboratory, we perform an analysis of B-+/- -> DK +/- decays, using decay modes in which the neutral D meson decays to either CP-eigenstates or non-CP-eigenstates. We measure the partial decay rate charge asymmetries for CP-even and CP-odd D final states to be A(CP+) = 0.25 +/- 0.06 +/- 0.02 and A(CP-) = 0.09 +/- 0.07 +/- 0.02, respectively, where the first error is the statistical and the second is the systematic uncertainty. The parameter A(CP+) is different from zero with a significance of 3.6 standard deviations, constituting evidence for direct CP violation. We also measure the ratios of the charged-averaged B partial decay rates in CP and non-CP decays, RCP+ 1.18 +/- 0.09 +/- 0.05 and RCP- = 1.07 +/- 0.08 +/- 0.04. We infer frequentist confidence intervals for the angle gamma of the unitarity triangle, for the strong phase difference delta(B), and for the amplitude ratio r(B), which are related to the B- -> DK- decay amplitude by r(B)e(i(delta B-gamma)) = A(B- -> (D) over bar K-0(-)) = A(B- -> (D) over bar K-0(-))/A(B- -> (DK-)-K-0). Including statistical and systematic uncertainties, we obtain 0: 24 < rB < 0: 45 ( 0: 06 < rB < 0: 51) and, modulo 180 degrees, 11.3 degrees < gamma < 22.7 degrees or 80.8 degrees < gamma < 99.2 degrees or 157.3 degrees < gamma < 168.7 degrees (7.0 degrees < gamma < 173.0 degrees) at the 68% ( 95%) confidence level. |
Address |
[Tico, J. Garra; Grauges, E.] Univ Barcelona, Fac Fis, Dept ECM, E-08028 Barcelona, Spain |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000282680100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
368 |
Permanent link to this record |
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Author |
BABAR Collaboration (del Amo Sanchez, P. et al); Lopez-March, N.; Martinez-Vidal, F.; Milanes, D.A.; Oyanguren, A. |
Title |
Search for b -> u transitions in B- -> DK- and D*K- decays |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
82 |
Issue |
7 |
Pages |
072006 - 18pp |
Keywords |
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Abstract |
We report results from an updated study of the suppressed decays We report results from an updated study of the suppressed decays B- -> DK- and B- -> D*K- followed by D -> K+ pi(-), where D-(*()0) indicates a D-(*()0)or a (D) over bar (()*()0) meson, and D* -> D pi(0) or D* -> D gamma. These decays are sensitive to the Cabibbo-Kobayashi-Maskawa unitarity triangle angle gamma due to interference between the b -> c transition B- -> D-(*K-)0(-) followed by the doubly Cabibbo-suppressed decay D-0 -> K+ pi(-), and the b -> u transition B- -> (D) over bar (()*()0) K- followed by the Cabibbo-favored decay (D) over bar (0) -> K+ pi(-). We also report an analysis of the decay B- -> D-(*())pi(-) with the D decaying into the doubly Cabibbo-suppressed mode D -> K+ pi(-). Our results are based on 467 x 10(6) Gamma(4S) -> BB- decays collected with the BABAR detector at SLAC. We measure the ratios R-(*()) of the suppressed ([K+ pi(-)](D)K- / pi(-)) to favored ([K+ pi(-)](D)K- / pi(-)) branching fractions as well as the CP asymmetries A(()*()) of those modes. We see indications of signals for the B- -> DK- and B- -> D-D pi 0(()*()) K- suppressed modes, with statistical significances of 2.1 and 2.2 sigma, respectively, and we measure: R-DK = (1.1 +/- 0: 6 +/- 0.2) x 10(-2); A(DK) = -0.86 +/- 0: 47(-0.16)(+0.12), R-(D pi 0)K* = (1.8 +/- 0: 9 +/- 0: 4) x 10(-2); A ((D pi 0)K)* = +0.77 +/- 0: 35 +/- 0.12; R-(D gamma)K* = (1.3 +/- 1.4 +/- 0.8) x 10(-2); A((D gamma)K)* = +0.36 +/- 0: 94(-0.41)(+0.25), where the first uncertainty is statistical and the second is systematic. We use a frequentist approach to obtain the magnitude of the ratio r(B) equivalent to vertical bar A(B- -> (D) over bar 0K(-))/A(B- -> (DK-)-K-0)vertical bar = (9.5(-4.1)(+5.1))%, with r(B) < 16: 7% at 90% confidence level. In the case of B- -> D*K- we find r(B) equivalent to vertical bar A(B- -> <(D)over bar>0K(-))/A(B- -> (DK-)-K-0)vertical bar = (9.6(-5.1)(+3.5))%, with r(B)* < 15.0% at 90% confidence level. |
Address |
[Sanchez, P. del Amo; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.] Univ Savoie, LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000282751100002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
359 |
Permanent link to this record |
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Author |
Esteves, J.N.; Joaquim, F.R.; Joshipura, A.S.; Romao, J.C.; Tortola, M.; Valle, J.W.F. |
Title |
A(4)-based neutrino masses with Majoron decaying dark matter |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
82 |
Issue |
7 |
Pages |
073008 - 8pp |
Keywords |
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Abstract |
We propose an A(4) flavor-symmetric SU(3) circle times SU(2) circle times U(1) seesaw model where lepton number is broken spontaneously. A consistent two-zero texture pattern of neutrino masses and mixing emerges from the interplay of type-I and type-II seesaw contributions, with important phenomenological predictions. We show that, if the Majoron becomes massive, such seesaw scenario provides a viable candidate for decaying dark matter, consistent with cosmic microwave background lifetime constraints that follow from current WMAP observations. We also calculate the subleading one-loop-induced decay into photons which leads to a monoenergetic emission line that may be observed in future x-ray missions such as Xenia. |
Address |
[Esteves, J. N.; Romao, J. C.] Inst Super Tecn, Dept Fis, P-1049001 Lisbon, Portugal, Email: joaomest@cftp.ist.utl.pt |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000282812200004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
360 |
Permanent link to this record |
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Author |
Fernandez-Martinez, E.; Li, T.; Pascoli, S.; Mena, O. |
Title |
Improvement of the low energy neutrino factory |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
81 |
Issue |
7 |
Pages |
073010 - 13pp |
Keywords |
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Abstract |
The low energy neutrino factory has been proposed as a very sensitive setup for future searches for CP violation and matter effects. Here we study how its performance is affected when the experimental specifications of the setup are varied. Most notably, we have considered the addition of the “platinum'' nu(mu) -> nu(e) channel. We find that, while theoretically the extra channel provides very useful complementary information and helps to lift degeneracies, its practical usefulness is lost when considering realistic background levels. Conversely, an increase in statistics in the ”golden'' nu(mu) -> nu(e) channel and, to some extent, an improvement in the energy resolution, lead to an important increase in the performance of the facility, given the rich energy dependence of the "golden'' channel at these energies. We show that a low energy neutrino factory with a baseline of 1300 km, muon energy of 4.5 GeV, and either a 20 kton totally active scintillating detector or 100 kton liquid argon detector, can have outstanding sensitivity to the neutrino oscillation parameters theta(13), delta, and the mass hierarchy. For our estimated exposure of 2: 8 x 10(23) kton x decays per muon polarity, the low energy neutrino factory has sensitivity to theta(13) and delta for sin(2)(2 theta(13)) > 10(-4) and to the mass hierarchy for sin(2)(2 theta(13)) > 10(-3) |
Address |
[Martinez, Enrique Fernandez] Max Planck Inst Phys & Astrophys, Werner Heisenberg Inst, D-80805 Munich, Germany, Email: enfmarti@mppmu.mpg.de |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000277201900018 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
458 |
Permanent link to this record |
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Author |
Gonzalez-Alonso, M.; Pich, A.; Prades, J. |
Title |
Violation of quark-hadron duality and spectral chiral moments in QCD |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
81 |
Issue |
7 |
Pages |
074007 - 10pp |
Keywords |
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Abstract |
We analyze the spectral moments of the V – A two-point correlation function. Using all known short-distance constraints and the most recent experimental data from tau decays, we determine the lowest spectral moments, trying to assess the uncertainties associated with the so-called violations of quark-hadron duality. We have generated a large number of acceptable spectral functions, satisfying all conditions, and have used them to extract the wanted hadronic parameters through a careful statistical analysis. We obtain accurate values for the chi PT couplings L-10 and C-87, and a realistic determination of the dimension six and eight contributions in the operator product expansion, O-6 = (-5.4(-1.6)(+3.6)) . 10(-3) GeV6 and O-8 = d(-8.9-(12.6)(7.4+)) 10(-3) GeV8, showing that the duality-violation effects have been underestimated in previous literature. |
Address |
[Gonzalez-Alonso, Martin; Pich, Antonio] Univ Valencia, CSIC, Dept Fis Teor, E-46071 Valencia, Spain |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000277201900025 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
459 |
Permanent link to this record |