| Records |
| Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
| Title |
Precision luminosity measurements at LHCb |
Type |
Journal Article |
| Year |
2014 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
9 |
Issue |
|
Pages  |
P12005 - 91pp |
| Keywords |
Pattern recognition, cluster finding, calibration and fitting methods; Instrumentation for particle accelerators and storage rings – high energy (linear accelerators, synchrotrons) |
| Abstract |
Measuring cross-sections at the LHC requires the luminosity to be determined accurately at each centre-of-mass energy root s. In this paper results are reported from the luminosity calibrations carried out at the LHC interaction point 8 with the LHCb detector for root s = 2.76, 7 and 8TeV (proton-proton collisions) and for root s(NN) = 5TeV (proton-lead collisions). Both the “van der Meer scan” and “beam-gas imaging” luminosity calibration methods were employed. It is observed that the beam density profile cannot always be described by a function that is factorizable in the two transverse coordinates. The introduction of a two-dimensional description of the beams improves significantly the consistency of the results. For proton-proton interactions at root s = 8TeV a relative precision of the luminosity calibration of 1.47% is obtained using van der Meer scans and 1.43% using beam-gas imaging, resulting in a combined precision of 1.12%. Applying the calibration to the full data set determines the luminosity with a precision of 1.16%. This represents the most precise luminosity measurement achieved so far at a bunched-beam hadron collider. |
| Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] CBPF, Rio De Janeiro, Brazil, Email: rosen.matev@cern.ch |
| Corporate Author |
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Thesis |
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| Publisher |
Iop Publishing Ltd |
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 |
1748-0221 |
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:000345859200021 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2030 |
| Permanent link to this record |
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| Author |
Pierre Auger Collaboration (Aab, A. et al); Pastor, S. |
| Title |
Muons in air showers at the Pierre Auger Observatory: Measurement of atmospheric production depth |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
90 |
Issue |
1 |
Pages |
012012 - 15pp |
| Keywords |
|
| Abstract |
The surface detector array of the Pierre Auger Observatory provides information about the longitudinal development of the muonic component of extensive air showers. Using the timing information from the flash analog-to-digital converter traces of surface detectors far from the shower core, it is possible to reconstruct a muon production depth distribution. We characterize the goodness of this reconstruction for zenith angles around 60 degrees and different energies of the primary particle. From these distributions, we define X-max(mu) as the depth along the shower axis where the production of muons reaches maximum. We explore the potentiality of X-max(mu) as a useful observable to infer the mass composition of ultrahigh-energy cosmic rays. Likewise, we assess its ability to constrain hadronic interaction models. |
| Address |
[Aab, A.; Buchholz, P.; Erfani, M.; Froehlich, U.; Heimann, P.; Homola, P.; Niechciol, M.; Ochilo, L.; Risse, M.; Yushkov, A.; Ziolkowski, M.] Univ Siegen, D-57068 Siegen, Germany |
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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 |
WOS:000339922100001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1866 |
| Permanent link to this record |
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| Author |
AGATA Collaboration (Crespi, F.C.L. et al); Gadea, A. |
| Title |
Isospin Character of Low-Lying Pygmy Dipole States in Pb-208 via Inelastic Scattering of O-17 Ions |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
113 |
Issue |
1 |
Pages |
012501 - 5pp |
| Keywords |
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| Abstract |
The properties of pygmy dipole states in Pb-208 were investigated using the Pb-208(O-17, O-17'gamma) reaction at 340 MeV and measuring the gamma decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted gamma rays and of the scattered particles were measured. The results are compared with (gamma, gamma') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2(+) and 3(-) states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first time. This has allowed us to extract the isoscalar component of the 1(-) excited states from 4 to 8 MeV. |
| Address |
[Crespi, F. C. L.; Bracco, A.; Nicolini, R.; Pellegri, L.; Leoni, S.; Avigo, R.; Bottoni, S.; Camera, F.; Ceruti, S.; Morales, A. I.; Vandone, V.; Pullia, A.] Univ Milan, Dipartimento Fis, I-20133 Milan, Italy, Email: angela.bracco@mi.infn.it |
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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:000338665200009 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1848 |
| Permanent link to this record |
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| Author |
Boucenna, M.S.; Morisi, S.; Valle, J.W.F. |
| Title |
Radiative neutrino mass in 3-3-1 scheme |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
90 |
Issue |
1 |
Pages |
013005 - 5pp |
| Keywords |
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| Abstract |
We propose a new radiative mechanism for neutrino mass generation based on the SU(3)(c) circle times SU(3)(L) circle times U(1)(X) electroweak gauge group. Lepton number is a symmetry of the Yukawa sector which is spontaneously broken in the gauge sector. As a result light Majorana masses arise from neutral gauge boson exchanges at the one-loop level. In addition to the isosinglet neutrinos that may be produced at the LHC through the extended gauge boson portals, the model contains new quarks which can also lie at the TeV scale, and which can provide a plethora of accessible collider phenomena. |
| Address |
[Boucenna, Sofiane M.; Valle, Jose W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: boucenna@ific.uv.es; |
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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 |
WOS:000338740800003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1844 |
| Permanent link to this record |
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| Author |
Celis, A.; Cirigliano, V.; Passemar, E. |
| Title |
Lepton flavor violation in the Higgs sector and the role of hadronic tau-lepton decays |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
89 |
Issue |
1 |
Pages |
013008 - 19pp |
| Keywords |
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| Abstract |
It has been pointed out recently that current low-energy constraints still allow for sizable flavor-changing decay rates of the 125 GeV boson into leptons, h -> tau l (l = e, mu). In this work we discuss the role of hadronic tau-lepton decays in probing lepton flavor violating couplings in the Higgs sector. At low energy, the effective Higgs coupling to gluons induced by heavy quarks contributes to hadronic tau decays, establishing a direct connection with the relevant process at the LHC, pp(gg) -> h -> tau l. Semileptonic transitions like tau -> l pi pi are sensitive to flavor-changing scalar couplings, while decays such as tau -> l eta((l)) probe pseudoscalar couplings, thus providing a useful low-energy handle to disentangle possible Higgs flavor violating signals at the LHC. As part of our analysis, we provide an appropriate description of all the relevant hadronic matrix elements needed to describe Higgs mediated tau -> pi pi transitions, improving over previous treatments in the literature. |
| Address |
[Celis, Alejandro] Univ Valencia, CSIC, IFIC, 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 |
WOS:000331868600001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1712 |
| Permanent link to this record |
