English
Related papers

Related papers: Spin correlations due to antishadowing

200 papers

Top-antitop pairs produced at hadron colliders are largely unpolarized, but their spins are highly correlated. The structure of these correlations varies significantly over top production phase space, allowing very detailed tests of the…

High Energy Physics - Phenomenology · Physics 2015-06-12 Matthew Baumgart , Brock Tweedie

Spin measurements are crucial in distinguishing major scenarios of TeV scale new physics once it is discovered at the LHC. We give a brief survey of methods of measuring the spin of new physics particles at the LHC. We focus on the case in…

High Energy Physics - Phenomenology · Physics 2008-12-25 Lian-Tao Wang , Itay Yavin

Spin correlations in the production of top-antitop quark ($t\bar{t}$) pairs at the Large Hadron Collider (LHC) are an experimentally verified prediction of the Standard Model. In this paper, we compute the full spin density matrix for…

High Energy Physics - Phenomenology · Physics 2021-09-17 Baptiste Ravina , Ethan Simpson , James Howarth

Spin effects in strong interaction high energy processes are subtle phenomena which involve both short and long distance physics and test perturbative and non perturbative aspects of QCD. Moreover, depending on quantities like interferences…

High Energy Physics - Phenomenology · Physics 2008-11-26 Mauro Anselmino

We compare the impact of top-quark spin polarization effects in Higgs boson production in association with top-quark pairs and in corresponding backgrounds at the LHC. Because of the spin-zero nature of the Higgs boson, one expects, in the…

High Energy Physics - Phenomenology · Physics 2014-10-21 Sanjoy Biswas , Rikkert Frederix , Emidio Gabrielli , Barbara Mele

We show how to observe sizable angular correlations between the decay products of the top quark and those of the anti-top quark in top quark pair production and decay at hadron colliders. These correlations result from the large asymmetry…

High Energy Physics - Phenomenology · Physics 2014-11-17 Gregory Mahlon , Stephen Parke

Recent measurements, in particular those on $\Lambda$ polarization and spin alignment of vector mesons in $e^+e^-$ annihilation at LEP, and those on the azimuthal asymmetry at HERA, have attracted much attention on the spin effects in high…

High Energy Physics - Phenomenology · Physics 2009-11-07 Zuo-tang Liang

We systematically study the possibility of determining the spin of new particles after their discovery at the LHC. We concentrate on angular correlations in cascade decays. Motivated by constraints of electroweak precision tests and the…

High Energy Physics - Phenomenology · Physics 2010-10-27 Lian-Tao Wang , Itay Yavin

The global spin polarization of hyperons in heavy-ion collisions have been investigated by including spin correlation effects among their constituent quarks. The available data on global spin polarizations of hyperons and spin alignments of…

High Energy Physics - Phenomenology · Physics 2026-03-12 Lucia Oliva , Qun Wang , Xin-Nian Wang

The measurement of top quark spin correlation is an important tool for precise studies of top quark interactions. In this letter I construct a quantization axis maximizing the spin correlation at the LHC within the Standard Model. Using…

High Energy Physics - Phenomenology · Physics 2009-11-10 Peter Uwer

Phenomena of rotation and oscillations of particle spin are discussed for particles rotating in storage ring. The fact that these effects are described by spin-dependent part of zero-angle scattering amplitude allows to use them for the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Vladimir G. Baryshevsky

Using an effective field theory approach for higher-spin fields, we derive the interactions of colour singlet and electrically neutral particles with a spin higher than unity, concentrating on the spin-3/2, spin-2, spin-5/2 and spin-3…

High Energy Physics - Phenomenology · Physics 2021-06-16 Juan Carlos Criado , Abdelhak Djouadi , Niko Koivunen , Martti Raidal , Hardi Veermäe

Spin effect on the pair production under circularly polarized fields are investigated. Significantly different from what momentum spirals caused by two counter-rotating fields with a time delay, we find for the first time that the spirals…

High Energy Physics - Phenomenology · Physics 2024-02-27 Li-Na Hu , Hong-Hao Fan , Orkash Amat , Suo Tang , Bai-Song Xie

We review the study of the charged Higgs and top quark associated production at the LHC with the presence of an additional scalar doublet. Top quark spin effects are related to the Higgs fermion couplings through this process. The angular…

High Energy Physics - Phenomenology · Physics 2014-04-22 Xue Gong , Zong-Guo Si , Shuo Yang , Ya-Juan Zheng

Modification of the particles in the course of the source evolution is considered. Influence of this effect on multiplicities and correlations of the particles is displayed, including an enhancement of the production rates and identical…

High Energy Physics - Phenomenology · Physics 2009-10-31 I. V. Andreev

Top quark pairs are produced with strongly correlated spins in the partonic reactions $q\bar{q}\to t\bar{t}$ and $gg\to t\bar{t}$. A complete description of these effects in terms of the spin density matrix of the $t\bar{t}$ system in…

High Energy Physics - Phenomenology · Physics 2009-10-28 Arnd Brandenburg

In this work we consider the QCD predictions for spin correlations in $t\bar{t}$ production in hadronic collisions. In view of recent tensions between experimental data and theoretical calculations, it has been argued that one should…

High Energy Physics - Phenomenology · Physics 2026-03-26 Paolo Nason , Emanuele Re , Luca Rottoli

The special role played by singly polarized high-energy hadron-hadron collisions in Spin Physics is discussed: In such processes, the measured and the calculated quantities can be and have been directly compared with each other --- without…

High Energy Physics - Phenomenology · Physics 2007-05-23 Meng Ta-chung

Recent measurements have revealed a significant suppression of multipion Bose-Einstein correlations in heavy-ion collisions at the LHC. The suppression may be explained by postulating coherent pion emission. Typically, the suppression of…

Nuclear Theory · Physics 2016-09-21 Dhevan Gangadharan

Question of the proper incorporation of spin effects in tau lepton decays is often of importance. In present work, case of the Z/gamma to tau+ tau- production mechanism is studied in detail. As an example, the effects due to the spin…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Pierzchala , E. Richter-Was , Z. Was , M. Worek