Records |
Author |
Aguilar-Saavedra, J.A.; Bernabeu, J.; Mitsou, V.A.; Segarra, A. |
Title |
The Z boson spin observables as messengers of new physics |
Type |
Journal Article |
Year |
2017 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
77 |
Issue |
4 |
Pages |
234 - 6pp |
Keywords |
|
Abstract |
We demonstrate that the eight multipole parameters describing the spin state of the Z boson are able to disentangle known Z production mechanisms and signals from new physics at the LHC. They can be extracted from appropriate asymmetries in the angular distribution of lepton pairs from the Z boson decay. The power of this analysis is illustrated by (1) the production of Z boson plus jets; (2) Z boson plus missing transverse energy; (3) W and Z bosons originating from the two-body decay of a heavy resonance. |
Address |
[Aguilar-Saavedra, J. A.] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain, Email: jaas@ugr.es |
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 |
|
Notes |
WOS:000399448700004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
3121 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aaboud, M. et al); Alvarez Piqueras, D.; Barranco Navarro, L.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Higon-Rodriguez, E.; Jimenez Pena, J.; King, M.; Lacasta, C.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Mitsou, V.A.; Pedraza Lopez, S.; Rodriguez Rodriguez, D.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Measurement of the W boson polarisation in t(t)over-barevents from pp collisions at root s=8 TeV in the lepton plus jets channel with ATLAS |
Type |
Journal Article |
Year |
2017 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
77 |
Issue |
4 |
Pages |
264 - 28pp |
Keywords |
|
Abstract |
This paper presents a measurement of the polarisation of W bosons from t (t) over bar t decays, reconstructed in events with one high-p(T) lepton and at least four jets. Data from pp collisions at the LHC were collected at root s = 8 TeV and correspond to an integrated luminosity of 20.2 fb(-1). The angle theta* between the b-quark from the top quark decay and a direct W boson decay product in the W boson rest frame is sensitive to the W boson polarisation. Two different W decay products are used as polarisation analysers: the charged lepton and the down-type quark for the leptonically and hadronically decaying W boson, respectively. The most precise measurement of the W boson polarisation via the distribution of cos theta* is obtained using the leptonic analyser and events in which at least two of the jets are tagged as b-quark jets. The fitted fractions of longitudinal, left-and right-handed polarisation states are F-0 = 0.709 +/- 0.019, F-L = 0.299 +/- 0.015 and F-R = – 0.008 +/- 0.014, and are the most precisely measured W boson polarisation fractions to date. Limits on anomalous couplings of the W tb vertex are set. |
Address |
[Jackson, P.; Lee, L.; Petridis, A.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
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 |
|
Notes |
WOS:000400235900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3133 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aaboud, M. et al); Alvarez Piqueras, D.; Barranco Navarro, L.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Jimenez Pena, J.; King, M.; Lacasta, C.; Lacuesta, V.R.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Mitsou, V.A.; Pedraza Lopez, S.; Rodriguez Rodriguez, D.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Luminosity determination in pp collisions at root s=8 TeV using the ATLAS detector at the LHC |
Type |
Journal Article |
Year |
2016 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
76 |
Issue |
12 |
Pages |
653 - 45pp |
Keywords |
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Abstract |
The luminosity determination for the ATLAS detector at the LHC during pp collisions at root s = 8 TeV in 2012 is presented. The evaluation of the luminosity scale is performed using several luminometers, and comparisons between these luminosity detectors are made to assess the accuracy, consistency and long-term stability of the results. A luminosity uncertainty of delta L/L = +/- 1.9% is obtained for the 22.7 fb(-1) of pp collision data delivered to ATLAS at root s = 8 TeV in 2012. |
Address |
[Corriveau, F.; Jackson, P.; Lee, L.; Petridis, A.; Robertson, S. H.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
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:000399838900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3137 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Study of charmonium production in b-hadron decays and first evidence for the decay B-s(0) -> phi phi phi |
Type |
Journal Article |
Year |
2017 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
77 |
Issue |
9 |
Pages |
609 - 18pp |
Keywords |
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Abstract |
Using decays to f-meson pairs, the inclusive production of charmonium states in b-hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. Denoting by B-C = B(b -> CX) x B(C -> phi phi) the inclusive branching fraction of a b hadron to a charmonium state C that decays into a pair of phi mesons, ratios R-C2(C1) = B-C1/B-C2 are determined as R-eta c(1S)(chi c0) = 0.147 +/- 0.023 +/- 0.011, R-eta c(1S)(chi c1) = 0.073 +/- 0.016 +/- 0.006, R-eta c(1S)(chi c2) = 0.081 +/- 0.013 +/- 0.005, R-chi c0(chi c1) = 0.50 +/- 0.11 +/- 0.01, R-chi c0(chi c2) = 0.56 +/- 0.10 +/- 0.01 and R-eta c(1S)(eta c(2S)) = 0.040 +/- 0.011 +/- 0.004. Here and below the first uncertainties are statistical and the second systematic. Upper limits at 90% confidence level for the inclusive production of X(3872), X(3915) and.c2(2P) states are obtained as R-chi c1(X(3872)) < 0.34, R-chi c0(X(3915)) < 0.12 and R-chi c2(chi c2(2P)) < 0.16. Differential cross-sections as a function of transverse momentum are measured for the eta(c)(1S) and chi(c) states. The branching fraction of the decay B-s(0). phi phi phi is measured for the first time, B(B-s(0) -> phi phi phi) = (2.15 +/- 0.54 +/- 0.28 +/- 0.21 B) x10(-6). Here the third uncertainty is due to the branching fraction of the decay B-s(0) -> phi phi, which is used for normalization. No evidence for intermediate resonances is seen. A preferentially transverse phi polarization is observed. Themeasurements allow the determination of the ratio of the branching fractions for the eta(c)(1S) decays to ff and p (p) over bar as B(eta(c)(1S) -> phi phi)/B(eta(c)(1S) -> p (p) over bar) = 1.79 +/- 0.14 +/- 0.32. |
Address |
[Bediaga, I.; Belloli, N.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Molina Rodriguez, J.; dos Reis, A. C.; Rodrigues, A. B.; Guimaraes, V. Salustino; Lavra, L. Soares; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil, Email: sergey.barsuk@cern.ch |
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 |
|
Notes |
WOS:000410893100005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3296 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Improved limit on the branching fraction of the rare decay K-S(0) -> mu(+)mu(-) |
Type |
Journal Article |
Year |
2017 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
77 |
Issue |
10 |
Pages |
678 - 12pp |
Keywords |
|
Abstract |
A search for the decay K-S(0) -> mu+ mu- is performed, based on a data sample of proton- proton collisions corresponding to an integrated luminosity of 3 fb(-1), collected by the LHCb experiment at centre-of- mass energies of 7 and 8 TeV. The observed yield is consistent with the background- only hypothesis, yielding a limit on the branching fraction of B( K-S(0) -> mu(+)mu(-)) < 0.8 (1.0) x 10(-9) at 90% ( 95%) confidence level. This result improves the previous upper limit on the branching fraction by an order of magnitude. |
Address |
[Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Molina Rodriguez, J.; dos Reis, A. C.; Rodrigues, A. B.; Salustino Guimaraes, V.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil |
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 |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000412907600003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3324 |
Permanent link to this record |