Computes entanglement negativities for the tripartite spin system in e+e- -> ttZ and projects that collective entanglement is accessible but genuine multipartite entanglement has limited sensitivity at a polarized ILC with expected luminosity.
A model independent spin analysis of fundamental particles using azimuthal asymmetries
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
Exploiting the azimuthal angle dependence of the density matrices we construct observables that directly measure the spin of a heavy unstable particle. A novelty of the approach is that the analysis of the azimuthal angle dependence in a frame other than the usual helicity frame offers an independent cross-check on the extraction of the spin. Moreover, in some instances when the transverse polarisation tensor of highest rank is vanishing, for an accidental or dynamical reason, the standard azimuthal asymmetries vanish and would lead to a measurement with a wrong spin assignment. In a frame such as the one we construct, the correct spin assignment would however still be possible. The method gives direct information about the spin of the particle under consideration and the same event sample can be used to identify the spins of each particle in a decay chain. A drawback of the method is that it is instrumental only when the momenta of the test particle can be reconstructed. However we hope that it might still be of use in situations with only partial reconstruction. We also derive the conditions on the production and decay mechanisms for the spins, and hence the polarisations, to be measured at a collider experiment. As an example for the use of the method we consider the simultaneous reconstruction, at the partonic level, of the spin of both the top and the $W$ in top pair production in $e^+ e^-$ in the semi-leptonic channel.
citation-role summary
citation-polarity summary
fields
hep-ph 4years
2026 4verdicts
UNVERDICTED 4roles
background 2polarities
background 2representative citing papers
Quantum information observables in LHC top quark pair production are modified by SMEFT dimension-6 operators in ways that depend on their CP properties, offering a complementary probe beyond standard observables.
Semi-leptonic h to VV* decays retain an effective two-qutrit description for quantum tomography and entanglement after including finite fermion masses and NLO corrections.
Spin-correlation asymmetries in same-sign WW production yield sensitivity to anomalous WWWW couplings comparable to transverse-mass distributions, and their combination improves Wilson-coefficient limits while respecting unitarity cuts.
citing papers explorer
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Tripartite Entanglement in $e^+ e^- \to t \bar{t} Z$
Computes entanglement negativities for the tripartite spin system in e+e- -> ttZ and projects that collective entanglement is accessible but genuine multipartite entanglement has limited sensitivity at a polarized ILC with expected luminosity.
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Quantumness of top quark pairs produced at LHC within SMEFT framework
Quantum information observables in LHC top quark pair production are modified by SMEFT dimension-6 operators in ways that depend on their CP properties, offering a complementary probe beyond standard observables.
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Quantum Tomography and Entanglement in Semi-Leptonic $h\to VV^*$ Decays at Higher Orders
Semi-leptonic h to VV* decays retain an effective two-qutrit description for quantum tomography and entanglement after including finite fermion masses and NLO corrections.
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Probing anomalous quartic gauge couplings in same-sign $W$ boson scattering with polarization and spin correlation
Spin-correlation asymmetries in same-sign WW production yield sensitivity to anomalous WWWW couplings comparable to transverse-mass distributions, and their combination improves Wilson-coefficient limits while respecting unitarity cuts.