| Records |
| Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
| Title |
Precision Measurement of the Mass and Lifetime of the Xi(0)(b) Baryon |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
113 |
Issue |
3 |
Pages |
032001 - 10pp |
| Keywords |
|
| Abstract |
Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb(-1) collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 Xi(0)(b) -> Xi(+)(c)pi(-), Xi(+)(c) -> pK(-)pi(+) signal decays are reconstructed. From this sample, the first measurement of the Xi(0)(b) baryon lifetime is made, relative to that of the Lambda(0)(b) baryon. The mass differences M(Xi(0)(b)) – M(Lambda(0)(b)) and M(Xi(+)(c)) – M(Lambda(+)(c)) are also measured with precision more than 4 times better than the current world averages. The resulting values are tau(Xi b0)/tau(Lambda b0) = 1.006 +/- 0.018 +/- 0.010, M(Xi(0)(b)) – M(Lambda(0)(b)) = 172.44 +/- 0.39 +/- 0.17 MeV/c(2), M(Xi(+)(c)) – M(Lambda(+)(c)) = 181.51 +/- 0.14 +/- 0.10 MeV/c(2), where the first uncertainty is statistical and the second is systematic. The relative rate of Xi(0)(b) to Lambda(0)(b) baryon production is measured to be f(Xi b0) B(Xi(0)(b) -> Xi(+)(c)pi(-)) B(Xi(+)(c) -> pK(-)pi(+))/f(Lambda b0) B(Lambda(0)(b) -> Lambda(+)(c)pi(-)) B(Lambda(+)(c) -> pK(-)pi(+)) = (1.88 +/- 0.04 +/- 0.03) x 10(-2), where the first factor is the ratio of fragmentation fractions, b -> Xi(0)(b) relative to b -> Lambda(0)(b). Relative production rates as functions of transverse momentum and pseudorapidity are also presented. |
Address  |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Kucewicz, W.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] CBPF, Rio De Janeiro, Brazil |
| 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 |
0031-9007 |
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 |
WOS:000341260100003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1912 |
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| Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
| Title |
Evidence for CP Violation in B+ -> p(p)over-barK(+) Decays |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
113 |
Issue |
14 |
Pages |
141801 - 9pp |
| Keywords |
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| Abstract |
Three-body B+ -> p (p) over barK(+) and B+ -> p (p) over bar pi(+) decays are studied using a data sample corresponding to an integrated luminosity of 3.0 fb(-1) collected by the LHCb experiment in proton-proton collisions at center-of-mass energies of 7 and 8 TeV. Evidence of CP violation in the B+ -> p (p) over barK(+) decay is found in regions of the phase space, representing the first measurement of this kind for a final state containing baryons. Measurements of the forward-backward asymmetry of the light meson in the p (p) over bar rest frame yield A(FB)(p (p) over barK(+), m(p (p) over bar) < 2.85 GeV/c(2)) = 0.495 +/- 0.012 (stat) +/- 0.007 (syst) and A(FB)(p<(p)over bar>pi(+), m(p (p) over bar) < 2.85 GeV/c(2)) = -0.409 +/- 0.033 (stat) +/- 0.006 (syst). In addition, the branching fraction of the decay B+ -> <(Lambda)over bar>(1520)p is measured to be B(B+ -> (Lambda) over bar (1520)p) = (3.15 +/- 0.48 (stat) +/- 0.07 (syst) +/- 0.26 (BF)) x 10(-7), where BF denotes the uncertainty on secondary branching fractions. |
| Address |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Kucewicz, W.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
| 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 |
0031-9007 |
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 |
WOS:000346502900005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2044 |
| Permanent link to this record |
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| Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
| Title |
Observation of Overlapping Spin-1 and Spin-3 (D)over-bar(0) K(-) Resonances at Mass 2.86 GeV/c(2) |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
113 |
Issue |
16 |
Pages |
162001 - 9pp |
| Keywords |
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| Abstract |
The resonant substructure of B-s(0) -> (D) over bar K-0(-)pi(+) decays is studied using a data sample corresponding to an integrated luminosity of 3.0 fb(-1) of pp collision data recorded by the LHCb detector. An excess at m((D) over bar K-0(-)) approximate to 2.86 GeV/c(2) is found to be an admixture of spin-1 and spin-3 resonances. Therefore, the D-sJ*(2860)(-) state previously observed in inclusive e(+)e(-) -> (D) over bar (K-X)-K-0 and pp -> (D) over bar (K-X)-K-0 processes consists of at least two particles. This is the first observation of a heavy flavored spin-3 resonance, and the first time that any spin-3 particle has been seen to be produced in B decays. The masses and widths of the new states and of the D-s2*(2573)(-) meson are measured, giving the most precise determinations to date. |
| Address |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
| 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 |
0031-9007 |
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 |
WOS:000344032500006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1997 |
| Permanent link to this record |
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| Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
| Title |
First Measurement of the Charge Asymmetry in Beauty-Quark Pair Production |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
113 |
Issue |
8 |
Pages |
082003 - 9pp |
| Keywords |
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| Abstract |
The difference in the angular distributions between beauty quarks and antiquarks, referred to as the charge asymmetry, is measured for the first time in b (b) over bar pair production at a hadron collider. The data used correspond to an integrated luminosity of 1.0 fb(-1) collected at 7 TeV center-of-mass energy in proton-proton collisions with the LHCb detector. The measurement is performed in three regions of the invariant mass of the b (b) over bar system. The results obtained are A(C)(b (b) over bar) (40 < M-b<(b)over bar> < 75 GeV/c(2)) = 0.4 +/- 0.4 +/- 0.3%, A(C)(b (b) over bar) (75 < M-b<(b)over bar> < 105 GeV/c(2)) = 2.0 +/- 0.9 +/- 0.6%, A(C)(b (b) over bar) (M-b (b) over bar > 10(5) GeV/c(2)) = 1.6 +/- 1.7 +/- 0.6%,where A(C)(b (b) over bar) is defined as the asymmetry in the difference in rapidity between jets formed from the beauty quark and antiquark, where in each case the first uncertainty is statistical and the second systematic. The beauty jets are required to satisfy 2 < eta < 4, E-T > 20 GeV, and have an opening angle in the transverse plane Delta phi > 2.6 rad. These measurements are consistent with the predictions of the standard model. |
| Address |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
| 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 |
0031-9007 |
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 |
WOS:000346504200005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2045 |
| Permanent link to this record |
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| Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
| Title |
Study of Beauty Hadron Decays into Pairs of Charm Hadrons |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
112 |
Issue |
20 |
Pages |
202001 - 9pp |
| Keywords |
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| Abstract |
First observations of the decays A(b)(0) -> A(c)(+)D((s))(-) are reported using data corresponding to an integrated luminosity of 3 fb(-1) collected at 7 and 8 TeV center-of- ass energies in proton-proton collisions with the LHCb detector. In addition, the most precise measurement of the branching fraction B(B-s(0) -> D+Ds-) is made and a search is performed for the decays B-0((s)) -> A(c)(+)A(c)(-). The results obtained are B(A(b)(0) -> A(c)(+)D(-))/B(A(b)(0) -> A(c)(+)D(s)(-)) = 0.042 +/- 0.003 (stat) +/- 0.003 (syst), [B(A(b)(0) -> A(c)(+)D(s)(-))/B((B) over bar (0) -> D+Ds-)]/[B(A(b)(0) -> A(c)(+)pi(-))/B((B) over bar (0) -> D+pi(-))] = 0.96 +/- 0.02 (stat) +/- 0.06 (syst), B(B-s(0) -> D+Ds-)/B((B) over bar (0) -> D+Ds-) = 0.038 +/- 0.004 (stat) +/- (syst), B((B) over bar (0) -> A(c)(+)A(c)(-))/B((B) over bar (0) -> D+Ds-) < 0.0022[95% C.L.], B(B-s(0) -> A(c)(+)A(c)(-)) /B(B-s(0) -> D+Ds-) < 0.30[95% C.L.]. Measurement of the mass of the A(b)(0) baryon relative to the (B) over bar (0) meson gives M(A(b)(0)) – M((B) over bar (0)) = 339.72 +/- 0.24 (stat) +/- 0.18 (syst) MeV/c(2). This result provides the most precise measurement of the mass of the A(b)(0) baryon to date. |
| Address |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Massafferri, A.; Nasteva, I.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
| 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 |
0031-9007 |
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 |
WOS:000336250100004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1793 |
| Permanent link to this record |
