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Related papers: $Z$-boson polarization as a model-discrimination a…

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We demonstrate that the 8 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…

High Energy Physics - Phenomenology · Physics 2017-05-24 J. A. Aguilar-Saavedra , J. Bernabéu , V. A. Mitsou , A. Segarra

Motivated by the growing interest in accessing the spin structure of multi-boson processes and in measuring quantum entanglement at high energies, we study polarisation and spin-correlation coefficients in di-boson systems. We show that…

High Energy Physics - Phenomenology · Physics 2025-01-13 Michele Grossi , Giovanni Pelliccioli , Alessandro Vicini

An introduction to spin techniques in particle physics is given. Among the topics covered are: helicity formalism and its applications to the decay and scattering of spin-1/2 and spin-1 particles, techniques for evaluating helicity…

High Energy Physics - Phenomenology · Physics 2009-09-25 Howard E. Haber

We propose a novel approach to measure spin polarization of nucleons produced in electron--positron collisions. Using existing tracking devices and supporting structure material, general-purpose spectrometers can be utilized as a…

High Energy Physics - Phenomenology · Physics 2025-01-07 Yu-Tie Liang , Xiao-Rong Lv , Andrzej Kupsc , Boxing Gou , Hai-Bo Li

Quantities like the fine structure constant at the pole of the Z boson and the anomalous magnetic moment of the muon are of profound importance for testing the Standard Model of elementary particle physics. Because these quantities are…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Groote

We demonstrate rigorously that in the absence of explicit spin-dependent forces one of the ground states of interacting bosons with spin is always fully polarized -- however complicated the many-body interaction potential might be.…

Statistical Mechanics · Physics 2009-11-07 Eli Eisenberg , Elliott H. Lieb

Gluons inside an unpolarized proton are in general linearly polarized. This polarization can, in principle, be used to determine the spin and parity of the newly found Higgs-like boson at the LHC. We focus here on the calculation of the…

High Energy Physics - Phenomenology · Physics 2013-10-21 Wilco J. den Dunnen , Marc Schlegel

In this contribution, we summarize and discuss recent theoretical progress on the Standard-Model calculation of joint polarized cross sections of massive multi-boson processes with fully leptonic decays. The topics include fixed-order…

High Energy Physics - Phenomenology · Physics 2025-09-25 Thi Nhung Dao , Duc Ninh Le

Pair production of heavy vector bosons is a key process at colliders: it allows to test our understanding of the Standard Model and to explore the existence of new physics through precision measurements of production rates and differential…

High Energy Physics - Phenomenology · Physics 2023-07-21 Rafael Aoude , Eric Madge , Fabio Maltoni , Luca Mantani

After a brief introduction into the general importance of polarization observables for the analysis of a reaction, the basic density matrix formalism for the description of polarization phenomena is outlined and illustrated by explicit…

Nuclear Theory · Physics 2015-05-13 Hartmuth Arenhoevel

We consider the decay of the $Z$ boson into three pseudoscalar bosons in a general two-Higgs-doublet model. Assuming $m_A$ to be very small, and that of the two physical neutral scalar bosons $h_1$ and $h_2$, $A$ only couples to $Z$ through…

High Energy Physics - Phenomenology · Physics 2009-10-30 E. Keith , Ernest Ma

Using the general, model independent form of the effective Hamiltonian, the general expressions of the longitudinal, normal and transversal polarization asymmetries for (l^-) and (l^+) and combinations of them for the exclusive (B -> K l^+…

High Energy Physics - Phenomenology · Physics 2009-11-07 T. M. Aliev , M. K. Cakmak , A. Ozpineci , M. Savci

With this paper we extend our studies [1] on polarized beams by distilling tools from the theory of principal bundles. Four major theorems are presented, one which ties invariant fields with the notion of normal form, one which allows one…

Accelerator Physics · Physics 2014-12-15 Klaus Heinemann , James A. Ellison , Desmond P. Barber , Mathias Vogt

The strongly interacting system created in ultrarelativistic nuclear collisions behaves almost as an ideal fluid with rich patterns of the velocity field exhibiting strong vortical structure. Vorticity of the fluid, via spin-orbit coupling,…

Nuclear Experiment · Physics 2024-10-30 Takafumi Niida , Sergei A. Voloshin

The successful LHC operation suggests going beyond the search of excess of events for the quest of new physics. We demonstrate that the eight multipole parameters describing the spin state of the W or Z bosons are able to disentangle their…

High Energy Physics - Phenomenology · Physics 2017-11-15 J. Bernabeu , A. Segarra

PROZA-M experiment results as well the proposal of a new spin program with the use of a polarized proton beam are presented. Significant asymmetries were observed in inclusive $\pi^0$ production. The new program proposes to study a wealth…

We develop polarization observables for the processes $\gamma N\to\pi\pi N$ and $\pi N\to\pi\pi N$, using both a helicity and hybrid helicity-transversity basis. Such observables are crucial if processes that produce final states consisting…

Nuclear Theory · Physics 2014-11-18 W. Roberts , T. Oed

We propose a new technique for determining the spin of new massive particles that might be discovered at the Large Hadron Collider. The method relies on pair-production of the new particles in a kinematic regime where the vector boson…

High Energy Physics - Phenomenology · Physics 2011-09-23 Matthew R. Buckley , Michael J. Ramsey-Musolf

Quasi-optical experiments are emerging as a powerful technique to probe magnetic transitions in molecular spin systems. However, the simultaneous presence of the electric- and magnetic-dipole induced transitions poses the challenge of…

Mesoscale and Nanoscale Physics · Physics 2026-02-10 Filippo Troiani , Athanassios K. Boudalis

We developed a method to analyze the polarization correlations of two baryons $B_{1}\bar{B}_{2}$ with various spin combinations in the annihilation process. We established spin density matrices for arbitrary spins in standard and Cartesian…

High Energy Physics - Phenomenology · Physics 2024-08-16 Zhe Zhang , Rong-Gang Ping , Tianbo Liu , Jiao Jiao Song , Weihua Yang , Ya-jin Zhou