Related papers: Heavy baryons as polarimeters at colliders
Being able to measure the polarization of quarks produced in various processes at the LHC would be of fundamental significance. Measuring the polarizations of quarks produced in new physics processes, once discovered, can provide crucial…
Polarization of strange quarks is preserved to a high degree when they hadronize into Lambda baryons, as observed in Z decays at LEP. This opens up the possibility for ATLAS and CMS to use strange-quark polarization measurements as a…
The process $pp \to W^-c$ produces polarized charm quarks. The polarization is expected to be partly retained in $\Lambda_c$ baryons when those form in the $c$-quark hadronization. We argue that it will likely be possible for ATLAS and CMS…
In this paper, some subtleties in the measurement of the transverse polarization of the produced hadrons on symmetric colliders -- such as the Large Hadron Collider when conducting the $pp$ collisions -- are revealed. It can be proved that…
Polarization and spin correlations have been studied in detail for top quarks at the LHC, but have been explored very little for the other flavors of quarks. In this paper we consider the processes $pp\to q\bar{q}$ with $q = b$, $c$ or $s$.…
Standard Model $t\bar t$ samples in ATLAS and CMS provide an opportunity to conduct measurements of the polarization of quarks produced in top-quark decays. The bottom quarks from the $t \to W^+ b$ decays, as well as the charm, strange, up…
Polarization and spin correlations have been explored very little for quarks other than the top. Utilizing the partial preservation of the quark's spin information in baryons in the jet produced by the quark, we examine possible analysis…
Several observables sensitive to the fragmentation of $b$-quarks into $b$-hadrons are measured using 36 fb${}^{-1}$ of $\sqrt s = 13$ TeV proton-proton collision data collected with the ATLAS detector at the LHC. Jets containing $b$-hadrons…
Transverse $\Lambda$ polarization observed over four decades ago contradicted expectations from early leading-order perturbative QCD calculations. Measurements of $\Lambda$ polarization from unpolarized $pp$ and $p$A collisions have been…
The first measurement of the polarization of charm baryons by the LHCb experiment recorded in fixed-target mode is presented. The polarization of $\Lambda_c$ baryons is studied in collisions of protons, at an energy of 2.51 TeV, incident on…
In the Standard Model, b quarks produced in e^+e^- annihilation at the Z^0 peak have a large average longitudinal polarization of -0.94. Some fraction of this polarization is expected to be transferred to b-flavored baryons during…
We study the polarized $\Lambda_b$ baryon semileptonic decay $\Lambda_b \to \Lambda_cl{\bar\nu}$ using perturbative QCD factorization theorem. In this approach heavy baryon transition form factors are expressed as the convolutions of hard…
We discuss the Lambda_b-polarization of the bottom baryon Lambda_b in its production and in its decay. Standard Model predictions for b-quark polarization on the Z-peak are reviewed, including beam-quark orientation effects and O(as)…
Polarized $\Lambda_b \to \Lambda \gamma$ decays at the Z pole are shown to be well suited for probing a large variety of New Physics effects. A new observable is proposed, the angular asymmetry between the $\Lambda_b$ spin and photon…
This paper presents an analysis of the $\Lambda^0_b\rightarrow J/\psi\Lambda$ angular distribution and the transverse production polarisation of $\Lambda^0_b$ baryons in proton-proton collisions at centre-of-mass energies of 7, 8 and 13…
An analysis of the decay $\Lambda_b \to J/\psi(\to\mu^+\mu^-)\Lambda(\to p \pi^-)$ decay is performed to measure the $\Lambda_b$ polarization and three angular parameters in data from pp collisions at $\sqrt{s} =$ 7 and 8 TeV, collected by…
The radiative decays of $b$-baryons facilitate the direct measurement of photon helicity in $b\to s\gamma$ transitions thus serving as an important test of physics beyond the Standard Model. In this paper we analyze the complete angular…
A study of the decay channels Lambda_{b}-->Lambda V, where V is a vector meson (1^-), has been done by putting together kinematical and dynamical analysis. An intensive use of the helicity formalism is involved on the kinematical side,…
Same- and opposite-sign charge asymmetries are measured in lepton+jets $t\bar{t}$ events in which a $b$-hadron decays semileptonically to a soft muon, using data corresponding to an integrated luminosity of 20.3 fb$^{-1}$ from…
The photon polarization in $b \to s \gamma$ transitions is measured for the first time in radiative b-baryon decays exploiting the unique spin structure of $\Lambda_b \to \Lambda \gamma$ decays. A data sample corresponding to an integrated…