|
Records |
Links |
|
Author |
Aguilar-Saavedra, J.A.; Bernabeu, J. |
|
|
Title |
W polarisation beyond helicity fractions in top quark decays |
Type |
Journal Article |
|
Year |
2010 |
Publication |
Nuclear Physics B |
Abbreviated Journal |
Nucl. Phys. B |
|
|
Volume |
840 |
Issue |
1-2 |
Pages |
349-378 |
|
|
Keywords |
|
|
|
Abstract |
We calculate the density matrix for the decay of a polarised top quark into a polarised W boson and a massive 17 quark, for the most general Wth vertex arising from dimension-six gauge-invariant effective operators. We show that, in addition to the well-known W helicity fractions, for polarised top decays it is worth defining and studying the transverse and normal W polarisation fractions, that is, the W polarisation alone two directions orthogonal to its momentum. In particular, a rather simple forward-backward asymmetry in the normal direction is found to be very sensitive to complex phases in one of the Wth anomalous couplings. This asymmetry, which indicates a normal W polarisation, can be generated for example by a P-odd. T-odd transition electric dipole moment. We also investigate the angular distribution of decay products in the top quark rest frame, calculating the spin analysing powers for a general Wth vertex. Finally we show that, using a combined fit to top decay observables and the t W cross section, at LHC it will be possible to obtain model-independent measurements of all the (complex) Wth couplings as well as the single top polarisation. Implications for spin correlations in top pair production are also discussed. |
|
|
Address |
[Aguilar-Saavedra, J. A.] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain, Email: jaas@ugr.es |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0550-3213 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
ISI:000281832900013 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ elepoucu @ |
Serial |
370 |
|
Permanent link to this record |
|
|
|
|
Author |
Aguilar-Saavedra, J.A.; Bernabeu, J. |
|
|
Title |
Breaking down the entire W boson spin observables from its decay |
Type |
Journal Article |
|
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
93 |
Issue |
1 |
Pages |
011301 - 6pp |
|
|
Keywords |
|
|
|
Abstract |
We discuss the eight independent spin observables for the W boson in terms of its vector and tensor polarizations and identify the angular distributions and asymmetries able to separate them in collider experiments. The results are applied to the study of polarized top quark decays and diboson resonances. These novel observables are of great value for disentangling new physics mechanisms in W boson production. |
|
|
Address |
[Aguilar-Saavedra, J. A.] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain |
|
|
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 |
1550-7998 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000368324500001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
no |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
2538 |
|
Permanent link to this record |