Records |
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
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 |
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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 |
|
Notes |
WOS:000459583400006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3921 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
Title |
Extraction of form Factors from a Four-Dimensional Angular Analysis of (B)over-bar -> D*l(-)(nu)over-bar(l) |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
123 |
Issue |
9 |
Pages |
091801 - 8pp |
Keywords |
|
Abstract |
An angular analysis of the decay (B) over bar -> D*l(-)(nu) over bar (l), l is an element of {e, mu}, is reported using the full e(+) e(-) collision data set collected by the BABAR experiment at the Upsilon(4S) resonance. One B meson from the Upsilon(4S) -> B (B) over bar decay is fully reconstructed in a hadronic decay mode, which constrains the kinematics and provides a determination of the neutrino momentum vector. The kinematics of the semileptonic decay is described by the dilepton mass squared, q(2), and three angles. The first unbinned fit to the full four-dimensional decay rate in the standard model is performed in the so-called Boyd-Grinstein-Lebed approach, which employs a generic q(2) parametrization of the underlying form factors based on crossing symmetry, analyticity, and QCD dispersion relations for the amplitudes. A fit using the more model-dependent Caprini-Lellouch-Neubert (CLN) approach is performed as well. Our form factor shapes show deviations from previous fits based on the CLN parametrization. The latest form factors also provide an updated prediction for the branching fraction ratio R(D*) B((B) over bar -> D* tau(-)(nu) over bar (tau)) /B((B) over bar -> D*l(-)(nu) over bar (l)) = 0.253 +/- 0.005. Finally, using the well-measured branching fraction for the (B) over bar -> D*l(-)(nu) over bar (l) decay, a value of vertical bar V-cb vertical bar = (38.36 +/- 0.90) x 10(-3) is obtained that is consistent with the current world average for exclusive (B) over bar -> D(*)l(-)(nu) over bar (l) decays and remains in tension with the determination from inclusive semileptonic B decays to final states with charm. |
Address |
[Lees, J. P.; Poireau, V; Tisserand, V] Univ Savoie, CNRS, IN2P3, LAPP, 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 |
0031-9007 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000483048500003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4123 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
Title |
Search for B- -> Lambda(p)over-bar nu(nu)over-bar with the BABAR experiment |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
100 |
Issue |
11 |
Pages |
111101 - 8pp |
Keywords |
|
Abstract |
A search for the rare flavor-changing neutral current process B- -> Lambda(p) over bar nu(nu) over bar using data from the BABAR experiment has been performed. A total of 424 fb(-1) of e(+) e(-) collision data collected at the center-of-mass energy of the Upsilon(4S) resonance is used in this study, corresponding to a sample of (471 +/- 3) x 10(6) B (B) over bar pairs. Signal B- -> Lambda(p) over bar nu(nu) over bar candidates arc identified by fast fully reconstructing a B+ decay in one of many possible exclusive decays to hadronic final states, then examining detector activity that is not associated with this reconstructed B+ decay for evidence of a signal B- -> Lambda(p) over bar nu(nu) over bar decay. The data yield is found to be consistent with the expected background contribution under a null signal hypothesis, resulting in an upper limit of B(B- -> Lambda(p) over bar nu(nu) over bar) < 3.0 x 10(-5) at the 90% confidence level. |
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 |
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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 |
2470-0010 |
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:000501488500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4223 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Babiano, V.; Caballero, L.; Calvo, D.; Ladarescu, I.; Olleros, P.; Domingo-Pardo, C. |
Title |
gamma-Ray position reconstruction in large monolithic LaCl3(Ce) crystals with SiPM readout |
Type |
Journal Article |
Year |
2019 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
931 |
Issue |
|
Pages |
1-22 |
Keywords |
Gamma-ray; Position-sensitive detectors; Monolithic crystals; Spatial resolution; Neural networks |
Abstract |
We report on the spatial response characterization of large LaCl3(Ce) monolithic crystals optically coupled to 8 x 8 pixel silicon photomultiplier (SiPM) sensors. A systematic study has been carried out for 511 keV gamma-rays using three different crystal thicknesses of 10 mm, 20 mm and 30 mm, all of them with planar geometry and a base size of 50 x 50 mm(2). In this work we investigate and compare two different approaches for the determination of the main gamma-ray hit location. On one hand, methods based on the fit of an analytical model for the scintillation light distribution provide the best results in terms of linearity and field of view, with spatial resolutions close to similar to 1 mm FWHM. On the other hand, position reconstruction techniques based on neural networks provide similar linearity and field-of-view, becoming the attainable spatial resolution similar to 3 mm FWHM. For the third space coordinate z or depth-of-interaction we have implemented an inverse linear calibration approach based on the cross-section of the measured scintillation-light distribution at a certain height. The detectors characterized in this work are intended for the development of so-called Total Energy Detectors with Compton imaging capability (i-TED), aimed at enhanced sensitivity and selectivity measurements of neutron capture cross sections via the time-of-flight (TOF) technique. |
Address |
[Babiano, V; Caballero, L.; Calvo, D.; Ladarescu, I; Olleros, P.; Domingo-Pardo, C.] Univ Valencia, Inst Fis Corpuscular, CSIC, Valencia, Spain, Email: domingo@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0168-9002 |
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:000466151600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
4015 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Baglio, J.; Campanario, F.; Glaus, S.; Muhlleitner, M.; Spira, M.; Streicher, J. |
Title |
Gluon fusion into Higgs pairs at NLO QCD and the top mass scheme |
Type |
Journal Article |
Year |
2019 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
79 |
Issue |
6 |
Pages |
459 - 9pp |
Keywords |
|
Abstract |
We present the calculation of the full next-to-leading order (NLO) QCD corrections to Higgs boson pair production via gluon fusion at the LHC, including the exact top-mass dependence in the two-loop virtual and one-loop real corrections. This is the first independent cross-check of the NLO QCD corrections presented in the literature before. Our calculation relies on numerical integrations of Feynman integrals, stabilised with integration-by-parts and a Richardson extrapolation to the narrow width approximation. We present results for the total cross section as well as for the invariant Higgs-pair-mass distribution at the LHC, including for the first time a study of the uncertainty due to the scheme and scale choice for the top mass in the loops. |
Address |
[Baglio, J.; Streicher, J.] Eberhard Karls Univ Tubingen, Inst Theoret Phys, Morgenstelle 14, D-72076 Tubingen, Germany, Email: julien.baglio@uni-tuebingen.de; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
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 |
1434-6044 |
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:000469782000003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4037 |
Permanent link to this record |