Records |
Author |
LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. |
Title |
First Measurement of Charm Production in its Fixed-Target Configuration at the LHC |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
122 |
Issue |
13 |
Pages |
132002 - 12pp |
Keywords |
|
Abstract |
The first measurement of heavy-flavor production by the LHCb experiment in its fixed-target mode is presented. The production of J/psi and D-0 mesons is studied with beams of protons of different energies colliding with gaseous targets of helium and argon with nucleon-nucleon center-of-mass energies of root s(NN) = 86.6 and 110.4 GeV, respectively. The J/psi and D-0 production cross sections in pHe collisions in the rapidity range [2, 4.6] are found to be sigma(J/psi) = 652 +/- 33(stat) +/- 42(syst) nb/nucleon and sigma(D0) = 80.8 +/- 2.4(syst) +/- 6.3(syst) μb/nucleon, where the first uncertainty is statistical and the second is systematic. No evidence for a substantial intrinsic charm content of the nucleon is observed in the large Bjorken-x region. |
Address |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Molina Rodriguez, J.; dos Reis, A. C.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] 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:000463900300006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3974 |
Permanent link to this record |
|
|
|
Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
Title |
Search for a Stable Six-Quark State at BABAR |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
122 |
Issue |
7 |
Pages |
072002 - 7pp |
Keywords |
|
Abstract |
Recent investigations have suggested that the six-quark combination uuddss could be a deeply bound state (S) that has eluded detection so far, and a potential dark matter candidate. We report the first search for a stable, doubly strange six-quark state in (sic) > S (Lambda) over bar(Lambda) over bar decays based on a sample of 90 x 10(6)(sic)(2S) and 110 x 10(6)(sic)(3S) decays collected by the BABAR experiment. No signal is observed, and 90% confidence level limits on the combined (sic)(2S, 3S) -> S (Lambda) over bar(Lambda) over bar branching fraction in the range (1.2-1.4) x 10(-7) are derived for m(s) < 2.05 GeV. These bounds set stringent limits on the existence of such exotic particles. |
Address |
[Lees, J. P.; Poireau, V; Tisserand, V] Univ Savoie, Lab Annecy le Vieux Phys Particules LAPP, CNRS IN2P3, F-74941 Annecy Le Vieux, France |
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:000459583400006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3921 |
Permanent link to this record |
|
|
|
Author |
LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. |
Title |
Observation of Two Resonances in the Lambda(0)(b)pi(+/-) Systems and Precise Measurement of Sigma(+/-)(b) and Sigma(*+/-)(b) Properties |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
122 |
Issue |
1 |
Pages |
012001 - 9pp |
Keywords |
|
Abstract |
The first observation of two structures consistent with resonances in the final states Lambda(0)(b)pi(-) and Lambda(0)(b)pi(+) thorn is reported using samples of pp collision data collected by the LHCb experiment at root s = 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb(-1). The ground states Sigma(+/-)(b) and Sigma(*+/-)(b) are also confirmed and their masses and widths are precisely measured. |
Address |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Kim, T.; Massafferri, A.; Molina Rodriguez, J.; Soares Lavra, I; Jadallah Aoude, R. Tourinho] 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:000455687500003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3875 |
Permanent link to this record |
|
|
|
Author |
Cirigliano, V.; Falkowski, A.; Gonzalez-Alonso, M.; Rodriguez-Sanchez, A. |
Title |
Hadronic tau Decays as New Physics Probes in the LHC Era |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
122 |
Issue |
22 |
Pages |
221801 - 7pp |
Keywords |
|
Abstract |
We analyze the sensitivity of hadronic tau decays to nonstandard interactions within the model-independent framework of the standard model effective field theory. Both exclusive and inclusive decays are studied, using the latest lattice data and QCD dispersion relations. We show that there are enough theoretically clean channels to disentangle all the effective couplings contributing to these decays, with the tau -> pi pi nu(tau) channel representing an unexpected powerful new physics probe. We find that the ratios of nonstandard couplings to the Fermi constant are bound at the subpercent level. These bounds are complementary to the ones from electroweak precision observables and pp -> tau nu(tau) measurements at the LHC. The combination of tau decay and LHC data puts tighter constraints on lepton universality violation in the gauge boson-lepton vertex corrections. |
Address |
[Cirigliano, Vincenzo] Los Alamos Natl Lab, Theoret Div, Los Alamos, NM 87545 USA |
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:000470885800008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4050 |
Permanent link to this record |
|
|
|
Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
Title |
Observation of the Decay D-0 -> K- pi(+) e(+) e(-) |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
122 |
Issue |
8 |
Pages |
081802 - 8pp |
Keywords |
|
Abstract |
We report the observation of the rare charm decay D-0 -> K-pi(+)e(+)e(-), based on 468 fb(-1) of e(+)e(-) annihilation data collected at or close to the center-of-mass energy of the (sic)(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. We find the branching fraction in the invariant mass range 0.675 < m(e(+)e(-)) < 0.875 GeV/c(2) of the electron-positron pair to be B(D-0 -> K-pi(+)e(+)e(-)) = (4.0 +/- 0.5 +/- 0.2 +/- 0.1) x 10(-6), where the first uncertainty is statistical, the second systematic, and the third due to the uncertainty in the branching fraction of the decay D-0 -> K-pi(+)pi(+)pi(-) used as a normalization mode. The significance of the observation corresponds to 9.7 standard deviations including systematic uncertainties. This result is consistent with the recently reported D-0 -> K-pi(+)mu(+)mu(-) branching fraction, measured in the same invariant mass range, and with the value expected in the standard model. In a set of regions of m(e(+)e(-)), where long-distance effects are potentially small, we determine a 90% confidence level upper limit on the branching fraction B(D-0 -> K-pi(+)e(+)e(-)) < 3.1 x 10(-6). |
Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules LAPP, F-74941 Annecy Le Vieux, France |
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:000459920400005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3926 |
Permanent link to this record |