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Related papers: Feed-down effect on $\Lambda$ spin polarization

200 papers

We examine the new physics sensitivity of the rare decay $\Lambda_b \to \Lambda \nu\bar\nu$ which can be accessible at future $Z$-pole machines like FCC-ee and CEPC. We find that the longitudinal polarization of $\Lambda_b$ baryons produced…

High Energy Physics - Phenomenology · Physics 2025-03-11 Wolfgang Altmannshofer , Sri Aditya Gadam , Kevin Toner

A QCD formula for the polarization in the large-p_T \Lambda hyperon production in the unpolarized nucleon-nucleon collision at large x_F is derived. We focus on the mechanism in which the chiral-odd spin-independent twist-3 quark…

High Energy Physics - Phenomenology · Physics 2009-10-31 Y. Kanazawa , Yuji Koike

The STAR Beam Energy Scan program has found a difference in the global polarization of $\Lambda$s and $\bar{\Lambda}$s produced in $Au+Au$ collisions. This difference is larger for lower center of mass collision energies. In this work we…

High Energy Physics - Phenomenology · Physics 2020-10-27 A. Ayala , E. Cuautle , I. Domínguez , I. Maldonado , J. Salinas , M. E. Tejeda-Yeomans

Polarization of $\Lambda$ hyperons has been observed in various collision systems over a wide range of collision energies over the last 50 years since its discovery in Fermilab in the 70's. The existing experimental and theoretical…

Nuclear Experiment · Physics 2023-07-17 Jan Vanek

Using the self-analyzing decay of the $\Lambda$, the longitudinal spin transfer $D_{LL'}$ to the hyperon from a polarized electron beam scattering off an unpolarized proton target can be determined. For $\Lambda$s produced in the current…

Nuclear Experiment · Physics 2023-01-18 Matthew McEneaney

In this paper we study transverse polarization of $\Lambda$ hyperons in single-inclusive leptonic annihilation. We show that when the transverse momentum of the $\Lambda$ baryon is measured with respect to the thrust axis, a transverse…

High Energy Physics - Phenomenology · Physics 2022-12-06 Leonard Gamberg , Zhong-Bo Kang , Ding Yu Shao , John Terry , Fanyi Zhao

Multiple polarization observables must be measured to access the amplitude structure of pseudoscalar meson photoproduction off the proton. The hyperon-producing reactions are especially attractive to study, since the weak decays allow…

Nuclear Experiment · Physics 2008-11-26 Reinhard Schumacher

In this work, we address the problem of longitudinal spin polarization of the $\Lambda$ hyperons produced in relativistic heavy-ion collisions. We combine a relativistic kinetic-theory framework that includes spin degrees of freedom treated…

High Energy Physics - Phenomenology · Physics 2024-05-09 Soham Banerjee , Samapan Bhadury , Wojciech Florkowski , Amaresh Jaiswal , Radoslaw Ryblewski

The longitudinal polarisation transfer from muons to lambda and anti-lambda hyperons, D_LL, has been studied in deep inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to lambda…

High Energy Physics - Experiment · Physics 2009-11-05 The COMPASS Collaboration , M. Alekseev

We study the production of longitudinally polarized Lambda-baryons in single-spin pp collisions at RHIC and HERA-N as a means of determining the spin-dependent Lambda fragmentation functions. It is shown that a measurement of the rapidity…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. de Florian , M. Stratmann , W. Vogelsang

The weak decay parameter $\alpha_-$ of the $\Lambda$ is an important quantity for the extraction of polarization observables in various experiments. Moreover, in combination with $\alpha_+$ from $\bar\Lambda$ decay it provides a measure for…

Nuclear Experiment · Physics 2019-10-29 D. G. Ireland , M. Döring , D. I. Glazier , J. Haidenbauer , M. Mai , R. Murray-Smith , D. Rönchen

The proton polarizability effect in the muonic-hydrogen Lamb shift comes out as a prediction of baryon chiral perturbation theory at leading order and our calculation yields for it: $\Delta E^{(\mathrm{pol})} (2P-2S) = 8^{+3}_{-1}\, \mu$eV.…

High Energy Physics - Phenomenology · Physics 2015-06-18 Jose Manuel Alarcón , Vadim Lensky , Vladimir Pascalutsa

We review studies of vortical motion and the resulting global polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons in heavy-ion collisions, in particular, within 3FD model. 3FD predictions for the global midrapidity polarization in the…

Nuclear Theory · Physics 2020-08-26 Yu. B. Ivanov , V. D. Toneev , A. A. Soldatov

We suggested that longitudinal polarization of Lambda produced in e+e- annihilation at LEP energies can provide useful information on hadronization mechanism in general and on testing the validity of different pictures for the spin content…

High Energy Physics - Phenomenology · Physics 2007-05-23 Liang Zuo-tang

Inclusive $H_b \to X_s \, \gamma$ decays, with $H_b$ a beauty baryon, are treated exploiting an expansion up to the third order in the inverse of the $b$ quark mass $m_b$ and to LO in $\alpha_s$, keeping the dependence on the hadron spin.…

High Energy Physics - Phenomenology · Physics 2024-10-10 Francesco Loparco

The $\Lambda$ spin polarization is a crucial probe of the gradients of velocity and temperature in the quark-gluon plasma generated in heavy-ion collisions. However, it is still not systematically used to tune hydrodynamic models. In this…

High Energy Physics - Phenomenology · Physics 2025-07-28 Andrea Palermo

We examine the T-odd transverse lepton and $\Lambda$ polarizations in the baryonic decays of $\Lambda_b\to\Lambda l^+l^- (l=e ,\mu)$ to study the T violating effects. We show that the lepton polarizations are suppressed but the $\Lambda$…

High Energy Physics - Phenomenology · Physics 2009-11-07 Chuan-Hung Chen , C. Q. Geng , J. N. Ng

Motivated by the key role of shear induced polarization in understanding the local spin polarization puzzle of $\Lambda$ hyperons in heavy ion collisions, we perform a complete analysis of spin polarization of massive fermion in a quantum…

High Energy Physics - Phenomenology · Physics 2024-12-02 Ziyue Wang , Shu Lin

The strangeness-changing ($\Delta S = 1$) weak baryon-baryon interaction is studied through the nonmesonic weak decay of double-$\Lambda$ hypernuclei. Besides the usual nucleon-induced decay $\Lambda N \to N N$ we discuss novel…

Nuclear Theory · Physics 2009-11-07 A. Parreno , A. Ramos , C. Bennhold

We study the production of polarized $\Lambda$ hyperon in semi-inclusive deep inelastic scattering off an unpolarized target. We include the cases in which the $\Lambda$ hyperon is longitudinally polarized or transversely polarized, and in…

High Energy Physics - Phenomenology · Physics 2017-04-26 Yongliang Yang , Zhun Lu