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| Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Observation of a New Excited D-s(+) Meson in B-0 -> D- D+ K+ pi(-) Decays | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 126 | Issue | 12 | Pages | 122002 - 11pp |
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| Abstract | Using pp collision data corresponding to an integrated luminosity of 5.4 fb(-1) collected with the LHCb detector at a center-of-mass energy of 13 TeV, the B-0 -> D- D+ K+ pi(-) decay is studied. A new excited D-s(+) meson is observed decaying into the D+K+pi(-) final state with large statistical significance. The pole mass and width, and the spin parity of the new state are measured with an amplitude analysis to be m(R) = 2591 +/- 6 +/- 7 MeV, Gamma(R) = 89 +/- 16 +/- 12 MeV, and J(P) = 0(-), where the first uncertainty is statistical and the second systematic. Fit fractions for all components in the amplitude analysis are also reported. The new resonance, denoted as D-s0(2590)(+), is a strong candidate to be the D-s(2(1)S(0))(+) state, the radial excitation of the pseudoscalar ground-state D-s(+) meson. | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Sicas CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000646119900007 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4806 | ||
| Permanent link to this record | |||||
| Author | Aiola, S.; Bandiera, L.; Cavoto, G.; De Benedetti, F.; Fu, J.; Guidi, V.; Henry, L.; Marangotto, D.; Martinez-Vidal, F.; Mascagna, V.; Mazorra de Cos, J.; Mazzolari, A.; Merli, A.; Neri, N.; Prest, M.; Romagnoni, M.; Ruiz Vidal, J.; Soldani, M.; Sytov, A.; Tikhomirov, V.; Vallazza, E. | ||||
| Title | Progress towards the first measurement of charm baryon dipole moments | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review D | Abbreviated Journal | Phys. Rev. D |
| Volume | 103 | Issue | 7 | Pages | 072003 - 15pp |
| Keywords |
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| Abstract | Electromagnetic dipole moments of short-lived particles are sensitive to physics within and beyond the Standard Model of particle physics but have not been accessible experimentally to date. To perform such measurements it has been proposed to exploit the spin precession of channeled particles in bent crystals at the LHC. Progress that enables the first measurement of charm baryon dipole moments is reported. In particular, the design and characterization on beam of silicon and germanium bent crystal prototypes, the optimization of the experimental setup, and advanced analysis techniques are discussed. Sensitivity studies show that first measurements of Lambda(+)(c) and Xi(+)(c) baryon dipole moments can he performed in two years of data taking with an experimental setup positioned upstream of the LHCb detector. | ||||
| Address | [Aiola, S.; De Benedetti, F.; Fu, J.; Henry, L.; Marangotto, D.; Merli, A.; Neri, N.] Ist Nazl Fis Nucl, Sez Milano, Milan, Italy | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2470-0010 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000648575400001 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4835 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Angular Analysis of the B+ -> K*(+)mu(+) mu(-) Decay | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 126 | Issue | 16 | Pages | 161802 - 11pp |
| Keywords |
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| Abstract | We present an angular analysis of the B+ -> K*(+)(-> K-S(0)pi(+))mu(+) mu(-) decay using 9 fb(-1) of pp collision data collected with the LHCb experiment. For the first time, the full set of CP-averaged angular observables is measured in intervals of the dimuon invariant mass squared. Local deviations from standard model predictions are observed, similar to those in previous LHCb analyses of the isospin-partner B-0 -> K*(0)mu(+)mu(-) decay. The global tension is dependent on which effective couplings are considered and on the choice of theory nuisance parameters. | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000652829600007 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4841 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Measurement of the prompt-production cross-section ratio sigma(chi(c2))/sigma(chi(c1)) in pPb collisions at root s(NN)=8.16 TeV | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review C | Abbreviated Journal | Phys. Rev. C |
| Volume | 103 | Issue | 6 | Pages | 064905 - 10pp |
| Keywords |
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| Abstract | This article reports the first measurement of prompt chi(c1) and chi(c2) charmonium production in nuclear collisions at Large Hadron Collider energies. The cross-section ratio sigma(chi(c2))/sigma(chi(c1)) is measured in pPb collisions at root s(NN) = 8.16 TeV, collected with the LHCb experiment. The chi(c1,2) states are reconstructed via their decay to a J/psi meson, subsequently decaying into a pair of oppositely charged muons, and a photon, which is reconstructed in the calorimeter or via its conversion in the detector material. The cross-section ratio is consistent with unity in the two considered rapidity regions. Comparison with a corresponding cross-section ratio previously measured by the LHCb Collaboration in pp collisions suggests that chi(c1) and chi(c2) states are similarly affected by nuclear effects occurring in pPb collisions. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9985 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000661749700003 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4872 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Observation of New Resonances Decaying to J=Psi K plus and J=Psi phi | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 127 | Issue | 8 | Pages | 082001 - 11pp |
| Keywords |
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| Abstract | The first observation of exotic states with a new quark content ccus decaying to the J/Psi K+ final state is reported with high significance from an amplitude analysis of the B+-> J/ Psi phi K+ decay. The analysis is carried out using proton-proton collision data corresponding to a total integrated luminosity of 9 fb- 1 collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. The most significant state, Z(cs)(4000)+, has a mass of 4003 +/- 6 (-14) (+4) MeV, a width of 131 +/- 15 +/- 26 MeV, and spin parity J(P) = 1(+), where the quoted uncertainties are statistical and systematic, respectively. A new 1(+) X(4685) state decaying to the J/Psi phi final state is also observed with high significance. In addition, the four previously reported J/Psi phi states are confirmed and two more exotic states, Z(cs) (4220) (+) and X(4630), are observed with significance exceeding 5 standard deviations. | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000686914400004 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4940 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Precise measurement of the f(s)/f(d) ratio of fragmentation fractions and of B-s(0) decay branching fractions | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review D | Abbreviated Journal | Phys. Rev. D |
| Volume | 104 | Issue | 3 | Pages | 032005 - 20pp |
| Keywords |
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| Abstract | The ratio of the B-s(0) and B-0 fragmentation fractions, f(s)/f(d), in proton-proton collisions at the LHC, is obtained as a function of B-meson transverse momentum and collision center-of-mass energy from the combined analysis of different B-decay channels measured by the LHCb experiment. The results are described by a linear function of the meson transverse momentum or with a function inspired by Tsallis statistics. Precise measurements of the branching fractions of the B-s(0) -> J/psi phi and B-s(0)-> D-s(-)pi(+) decays are performed, reducing their uncertainty by about a factor of 2 with respect to previous world averages. Numerous B-s(0) decay branching fractions, measured at the LHCb experiment, are also updated using the new values of f(s)/f(d) and branching fractions of normalization channels. These results reduce a major source of systematic uncertainty in several searches for new physics performed through measurements of B-s(0) branching fractions. | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2470-0010 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000686913600001 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4947 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Measurement of CP asymmetry in D-0 -> KS0 KS0 decays | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review D | Abbreviated Journal | Phys. Rev. D |
| Volume | 104 | Issue | 3 | Pages | L031102 - 11pp |
| Keywords |
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| Abstract | A measurement of the CP asymmetry in D-0 -> (KSKS0)-K-0 decays is reported, based on a data sample of proton-proton collisions collected by the LHCb experiment from 2015 to 2018, corresponding to an integrated luminosity of 6 fb(-1). The flavor of the D-0 candidate is determined using the charge of the D-*+/- meson, from which the decay is required to originate. The D-0 -> K+K- decay is used as a calibration channel. The time-integrated CP asymmetry for the D-0 -> (KSKS0)-K-0 mode is measured to be A(CP)(D-0 -> (KSKS0)-K-0) = (-3.1 +/- 1.2 +/- 0.4 +/- 0.2), where the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty on the CP asymmetry of the calibration channel. This is the most precise determination of this quantity to date. | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2470-0010 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000692072800012 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4954 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. | ||||
| Title | Observation of new excited Bs0 states | Type | Journal Article | ||
| Year | 2021 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
| Volume | 81 | Issue | 7 | Pages | 601 - 11pp |
| Keywords |
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| Abstract | A structure is observed in the B +/- K -/+ mass spectrum in a sample of proton-proton collisions at centre-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of 9 fb-1. The structure is interpreted as the result of overlapping excited Bs0</mml:msubsup> states. With high significance, a two-peak hypothesis provides a better description of the data than a single resonance. Under this hypothesis the masses and widths of the two states, assuming they decay directly to B +/- K -/+, are determined to be m1 = 6063.5 +/- 1.2 (stat) +/- 0.8 (syst) MeV Gamma 1 = 26 +/- 4 (stat) +/- 4 (syst) MeV m2 = 6114 +/- 3 (stat) +/- 5 (syst) MeV Gamma 2 = 66 +/- 18 (stat) +/- 21 (syst) MeV Alternative values assuming a decay through B +/- K -/+, with a missing photon from the B +/- -> B +/- gamma decay, which are shifted by approximately 45 MeV, are also determined. The possibility of a single state decaying in both channels is also considered. The ratio of the total production cross-section times branching fraction of the new states relative to the previously observed Bs20 state is determined to be 0.87 +/- 0.15 (stat)+/- 0.19 (syst). |
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| Address | [Leite, J. Baptista; Bediaga, I.; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Kucewicz, W.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fisicas CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Springer | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1434-6044 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000691564500002 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4957 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Observation of the Mass Difference Between Neutral Charm-Meson Eigenstates | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 127 | Issue | 11 | Pages | 111801 - 12pp |
| Keywords |
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| Abstract | A measurement of mixing and CP violation in neutral charm mesons is performed using data reconstructed in proton-proton collisions collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4 fb(-1). A total of 30.6 million D0 -> K-s(0)pi(+)pi(-) decays are analyzed using a method optimized for the measurement of the mass difference between neutral charmmeson eigenstates. Allowing for CP violation in mixing and in the interference between mixing and decay, the mass and decay-width differences are measured to be x(CP) = [3.97 +/- 0.46(stat) +/- 0.29(syst)] x 10(-3) and y(CP) = [4.59 +/- 1.20(stat) +/- 0.85(syst)] x 10(-3), respectively. The CP-violating parameters are measured as Delta x= [-0.27 +/- 0.18(stat)+/- 0.01(syst)] x 10 (-3) and Delta y = [0.20 +/- 0.36(stat) +/- 0.13(syst)] x 10(-3). This is the first observation of a nonzero mass difference in the D-0 meson system, with a significance exceeding seven standard deviations. The data are consistent with CP symmetry and improve existing constraints on the associated parameters. | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000693639800004 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4965 | ||
| Permanent link to this record | |||||
| Author | LHCb Collaboration (Aaij, R. et al); Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Branching Fraction Measurements of the Rare B-s(0) -> phi mu(+)mu(-) and B-s(0)-> f(2)' (1525)mu(+)mu(-) Decays | Type | Journal Article | ||
| Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 127 | Issue | 15 | Pages | 151801 - 11pp |
| Keywords |
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| Abstract | The branching fraction of the rare B-s(0) -> phi mu(+)mu(-) decay is measured using data collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to integrated luminosities of 1, 2, and 6 fb(-1), respectively. The branching fraction is reported in intervals of q(2), the square of the dimuon invariant mass. In the q(2) region between 1.1 and 6.0 GeV2/c(4) , the measurement is found to lie 3.6 standard deviations below a standard model prediction based on a combination of light cone sum rule and lattice QCD calculations. In addition, the first observation of the rare B-s(0)-> f(2)' (1525)mu(+)mu(-) decay is reported with a statistical significance of 9 standard deviations and its branching fraction is determined. | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil | ||||
| Corporate Author | Thesis | ||||
| Publisher | Amer Physical Soc | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000704696500005 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4987 | ||
| Permanent link to this record | |||||