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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Porous Janus materials with unique asymmetries and functionality

Porous Janus materials have attracted widespread attention due to their asymmetry in wettability, charge, pore size or structure, thermal/electrical conductivity, and chemical activity, among other properties. Multifunction integration and unique directional manipulation of liquid, ions, or gas within porous Janus materials enable rapid progress in diverse applications such as water-oil separation, fog collection, personal moisture and healthcare management, energy conversion, desalination, sensor devices, and biomedical applications. Additionally, compared with conventional homogeneous materials, porous Janus materials not only showcase superior performance and energetic potential but also open up new applications by virtue of the synergistic or independent effects of asymmetry. This in-depth review systematically analyzes the research progress of porous Janus materials, highlighting fabrication strategies, synergistic/independent work mechanisms, and emerging advanced applications. Finally, ongoing challenges and outlook for the future research of porous Janus materials are presented.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Transverse single-spin asymmetries in $γ$ SIDIS as a direct probe of quark-gluon-quark longitudinal momentum structure

Transverse single-spin asymmetries in the semi-inclusive deep-inelastic production of isolated photons ($\gamma$SIDIS), $A_{UT}^{\gamma {\rm SIDIS}}$, provide an unprecedented opportunity to extract the quark-gluon-quark correlators $F_{FT}(x,x')$ and $G_{FT}(x,x')$ point-by-point in their full support $x,x'$. We utilize realistic models for these functions, based on input from the Sivers transverse momentum dependent parton distribution function and imposing constraints from the $d_2$ matrix element calculated in lattice QCD, in order to provide numerical estimates for $A_{UT}^{\gamma {\rm SIDIS}}$ at the Electron-Ion Collider (EIC). We thoroughly explore the EIC phase space in order to isolate in which regions the asymmetry can be sizable, finding it can be as much as $10\%$ or larger for certain kinematics. Given that $F_{FT}(x,x')$ and $G_{FT}(x,x')$ are basically unknown, $A_{UT}^{\gamma {\rm SIDIS}}$ will be an important future measurement to learn about multi-parton correlations in the nucleon.

Electron-Ion Collider↗
DOE OSTI2025

Probing hard/soft factorization via beam-spin asymmetry in exclusive pion electroproduction from the proton

Deep exclusive meson production (DEMP) reactions, such as $p(\vec{e}, e' π^+)n$, provide opportunities to study the three-dimensional structure of the nucleon through differential cross section and beam- and target-spin asymmetry measurements. This work aims to probe the onset of the hard/soft factorization regime through the exclusive $p(\vec{e}, e' π^+)n$ reaction, as measured in the KaonLT experiment at Jefferson Lab Hall C. A 10.6 GeV longitudinally polarized electron beam was incident on an unpolarized liquid hydrogen target, and the scattered electron and produced meson were detected in two magnetic focusing spectrometers, enabling precision cross section measurements. The cross section ratio $σ_{LT'}/σ_0$ was extracted from the beam-spin asymmetry $A_{LU}$. The t -dependence of $σ_{LT'}/σ_0$ was determined at fixed $Q^2$ and $x_B$ over a range of kinematics from 2 < $Q^2$ < 6 GeV$^2$ above the resonance region ($W$ > 2 GeV). Furthermore, these data are combined with recent results from CLAS/CLAS12 to determine the $Q^2$-dependence of at two $(x_B, t)$ settings. This was fairly flat, with $Q^2$ not having a measurable effect on the value of in the range explored. Results are compared to predictions from the generalized parton distribution (GPD) formalism, which relies explicitly on hard/soft factorization, and Regge formalism. The Regge models better predict $σ_{LT'}/σ_0$, which suggests that the factorization regime is not yet reached.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS2023

Hemispheric Asymmetry of the Annual and Semiannual Variation of Thermospheric Composition

We examine hemispheric asymmetry of the annual and semiannual variation of the ratio of O and N 2 concentrations ( O/N 2 ) using observations by the Global Ultraviolet Imager (GUVI) instrument onboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics satellite and compare them with Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension (WACCM-X) model simulations. We found that in the equatorial region, the “equinox peaks” of the observed O/N 2 are near the end of March and October, and the two annual lows are near the beginning of July and January. Compared to the equatorial region, in the northern hemisphere (NH) low latitudes, the first “equinox peak” clearly shifts toward the December solstice, whereas in the southern hemisphere (SH) low latitudes, the “equinox peaks” shift toward the June solstice (JS), forming the hemispheric asymmetry characteristics of the annual and semiannual variation. Seasonal variation of O/N 2 shows no apparent phase variation with altitude, and the annual and semiannual pattern is consistent from year to year. WACCM-X reproduces the observed annual and semiannual pattern in NH but in SH, it simulates an annual variation instead of the observed annual and semiannual variation. The largest discrepancy occurs near JS in the lower and middle thermosphere: the simulated O density has an annual high near JS in SH; the simulated N 2 density has an annual high near JS in NH but a predominant annual low near JS in SH. These are not in the GUVI data. A weaker thermospheric meridional circulation in the winter hemisphere, or a reduced summer-to-winter latitudinal gradient of neutral temperature in WACCM-X simulations would make model-data comparisons more consistent.

thermosphere composition↗
DOE OSTI2023

Measurement of CP asymmetries in ${D}_{(s)}^{+}\to \eta {\pi}^{+}$ and ${D}_{(s)}^{+}\to {\eta}^{\prime }{\pi}^{+}$ decays

Searches for CP violation in the decays ${D}_{(s)}^{+}\to \eta {\pi}^{+}$ and ${D}_{(s)}^{+}\to {\eta}^{\prime }{\pi}^{+}$ are performed using pp collision data corresponding to 6 fb –1 of integrated luminosity collected by the LHCb experiment. The calibration channels ${D}_{(s)}^{+}\to \phi {\pi}^{+}$ are used to remove production and detection asymmetries. The resulting CP-violating asymmetries are $\mathcal{A}^{CP} = (D^+ \to ηπ^+) = (0.34 ± 0.66 ± 0.16 ± 0.05)$ %, $\mathcal{A}^{CP} = (D^+_s \to ηπ^+) = (0.32 ± 0.51 ± 0.12)$ %, $\mathcal{A}^{CP} = (D^+ \to η'π^+) = (0.49 ± 0.18 ± 0.06 ± 0.05)$ %, $\mathcal{A}^{CP} = (D^+_s \to η'π^+) = (0.01 ± 0.12 ± 0.08)$ %, where the first uncertainty is statistical, the second is systematic and the third, relevant for the D + channels, is due to the uncertainty on ${\mathcal{A}}^{CP}=\left({D}^{+}\to \phi {\pi}^{+}\right)$. These measurements, currently the most precise for three of the four channels considered, are consistent with the absence of CP violation. A combination of these results with previous LHCb measurements is presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Measurement of branching-fraction ratios and CP asymmetries in B± → DCP±K± decays at Belle and Belle II

Abstract We report results from a study ofB ± → DK ± decays followed byDdecaying to theCP-even final stateK + K − and CP-odd final state$$ {K}_S^0{\pi}^0 $$ K S 0 π 0 , whereDis an admixture ofD 0 and$$ {\overline{D}}^0 $$ D ¯ 0 states. These decays are sensitive to the Cabibbo-Kobayashi-Maskawa unitarity-triangle angleϕ 3 . The results are based on a combined analysis of the final data set of 772×10 6 $$ B\overline{B} $$ B B ¯ pairs collected by the Belle experiment and a data set of 198×10 6 $$ B\overline{B} $$ B B ¯ pairs collected by the Belle II experiment, both in electron-positron collisions at the Υ(4S) resonance. We measure the CP asymmetries to be$$ \mathcal{A} $$ A CP+ = (+12.5±5.8±1.4)% and$$ \mathcal{A} $$ A CP− = (−16.7±5.7±0.6)%, and the ratios of branching fractions to be$$ \mathcal{R} $$ R CP+ = 1.164±0.081±0.036 and$$ \mathcal{R} $$ R CP− = 1.151±0.074±0.019. The first contribution to the uncertainties is statistical, and the second is systematic. The asymmetries$$ \mathcal{A} $$ A CP+ and$$ \mathcal{A} $$ A CP− have similar magnitudes and opposite signs; their difference corresponds to 3.5 standard deviations. From these values we calculate 68.3% confidence intervals of (8.5 ° <ϕ 3 < 16.5 ° ) or (84.5 ° <ϕ 3 < 95.5 ° ) or (163.3 ° <ϕ 3 < 171.5 ° ) and 0.321 B< 0.465.

Physics↗
DOE OSTI2020

Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at $ \sqrt{s} $ = 13 TeV

AbstractThe parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric $ \left({\hat{d}}_{\mathrm{t}}\right) $ and chromomagnetic $ \left({\hat{\mu}}_{\mathrm{t}}\right) $ moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb$^{−1}$. The linearized variable $ {A}_{\mathrm{FB}}^{(1)} $ is used to approximate the asymmetry. Candidate $ \mathrm{t}\overline{\mathrm{t}} $ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for $ \mathrm{t}\overline{\mathrm{t}} $ final states. The values found for the parameters are $ {A}_{\mathrm{FB}}^{(1)}={0.048}_{-0.087}^{+0.095}{\left(\mathrm{stat}\right)}_{-0.029}^{+0.020}\left(\mathrm{syst}\right),{\hat{\mu}}_{\mathrm{t}}=-{0.024}_{-0.009}^{+0.013}{\left(\mathrm{stat}\right)}_{-0.011}^{+0.016}\left(\mathrm{syst}\right), $ and a limit is placed on the magnitude of $ \left|{\hat{d}}_{\mathrm{t}}\right| $< 0.03 at 95% confidence level.[graphic not available: see fulltext]

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2023

Measurement of CP asymmetries and branching fraction ratios of B – decays to two charm mesons

The CP asymmetries of seven B – decays to two charm mesons are measured using data corresponding to an integrated luminosity of 9 fb –1 of proton-proton collisions collected by the LHCb experiment. Decays involving a D *0 or ${D}_s^{\ast -}$ meson are analysed by reconstructing only the D 0 or ${D}_s^{-}$ decay products. This paper presents the first measurement of $\mathcal{A}$ CP (B – → ${D}_s^{\ast -}$ D 0 ) and $\mathcal{A}$ CP (B – → ${D}_s^{-}$D $\ast$0 ), and the most precise measurement of the other five CP asymmetries. There is no evidence of CP violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Measurements of $$ {K}_S^0 $$-$$ {K}_L^0 $$ asymmetries in the decays $$ {\Lambda}_c^{+}\to p{K}_{L,S}^0 $$, $$ p{K}_{L,S}^0{\pi}^{+}{\pi}^{-} $$ and $$ p{K}_{L,S}^0{\pi}^0 $$

Abstract Usinge + e − annihilation data sets corresponding to an integrated luminosity of 4.5 fb −1 , collected with the BESIII detector at center-of-mass energies between 4.600 and 4.699 GeV, we report the first measurements of the absolute branching fractions$$ \mathcal{B}\left({\Lambda}_c^{+}\to p{K}_L^0\right) $$ B Λ c + → p K L 0 = (1.67±0.06±0.04)%,$$ \mathcal{B}\left({\Lambda}_c^{+}\to p{K}_L^0{\pi}^{+}{\pi}^{-}\right) $$ B Λ c + → p K L 0 π + π − = (1.69±0.10±0.05)%, and$$ \mathcal{B}\left({\Lambda}_c^{+}\to p{K}_L^0{\pi}^0\right) $$ B Λ c + → p K L 0 π 0 = (2.02±0.13±0.05)%, where the first uncertainties are statistical and the second systematic. Combining with the known branching fractions of$$ {\Lambda}_c^{+}\to p{K}_S^0 $$ Λ c + → p K S 0 ,$$ {\Lambda}_c^{+}\to p{K}_S^0{\pi}^{+}{\pi}^{-} $$ Λ c + → p K S 0 π + π − , and$$ {\Lambda}_c^{+}\to p{K}_S^0{\pi}^0 $$ Λ c + → p K S 0 π 0 , we present the first measurements of the$$ {K}_S^0 $$ K S 0 -$$ {K}_L^0 $$ K L 0 asymmetries$$ R\left({\Lambda}_c^{+},{K}_{S,L}^0X\right)=\frac{\mathcal{B}\left({\Lambda}_c^{+}\to {K}_S^0X\right)-\mathcal{B}\left({\Lambda}_c^{+}\to {K}_L^0X\right)}{\mathcal{B}\left({\Lambda}_c^{+}\to {K}_S^0X\right)+\mathcal{B}\left({\Lambda}_c^{+}\to {K}_L^0X\right)} $$ R Λ c + K S , L 0 X = B Λ c + → K S 0 X − B Λ c + → K L 0 X B Λ c + → K S 0 X + B Λ c + → K L 0 X in charmed baryon decays:$$ R\left({\Lambda}_c^{+},p{K}_{S,L}^0\right)=-0.025\pm 0.031 $$ R Λ c + p K S , L 0 = − 0.025 ± 0.031 ,$$ R\left({\Lambda}_c^{+},p{K}_{S,L}^0{\pi}^{+}{\pi}^{-}\right)=-0.027\pm 0.048 $$ R Λ c + p K S , L 0 π + π − = − 0.027 ± 0.048 and$$ R\left({\Lambda}_c^{+},p{K}_{S,L}^0{\pi}^0\right)=-0.015\pm 0.046 $$ R Λ c + p K S , L 0 π 0 = − 0.015 ± 0.046 . No significant asymmetries with statistical significance are observed.

Physics↗
DOE OSTI2022

Prospects for ${B}_{(s)}^0 $ → π$^0$π$^0$ and ${B}_{(s)}^0 $ → ηη modes and corresponding CP asymmetries at Tera-Z

The physics potential of measuring $B^0_{(s)}$ → $π^0π^0$ and $B^0_{(s)}$ → $ηη$ decays via four-photon final states at Tera-Z phase of CEPC or FCC-ee is investigated in this paper. We propose an electromagnetic calorimeter (ECAL) with both high energy resolution and excellent separation power to efficiently reconstruct $π^0$ and $η$ from hadronic final states with high photon multiplicity. The resulting B-meson mass resolution is approximately 30 MeV, allowing 3 $σ$ separation between B 0 and $B^0_{(s)}$. With the assistance of the b-jet tagging, the relative sensitivities to B 0 → $π^0π^0$, $B^0_{(s)}$ → $π^0π^0$, B 0 → $ηη$, and $B^0_{(s)}$ → $ηη$ signal strengths at Tera-Z are projected as 0.45%, 4.5%, 18%, and 0.95%, respectively. Their dependence on various detector performances is also discussed. In addition, B 0 → $π^0π^0$ and its two isospin-related modes are paid special attention due to their roles in the determination of the CKM angle α (Φ 2 ). The anticipated precisions of their branching-ratio and CP-asymmetry measurements at Tera-Z are evaluated. We show that the measurement of the time-integrated B 0 → $π^0π^0$ CP asymmetry at Tera-Z is complementary to B-factory ones. The precision on α combining Z- and B-factory results reaches 0.4°, lower than the systematic uncertainties attached to isospin breaking.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2026

Dihadron azimuthal asymmetry and light-quark dipole moments at the Electron-Ion Collider

Here, we propose a novel method to probe light-quark dipole moments by examining the azimuthal asymmetries between a collinear pair of hadrons in semi-inclusive deep inelastic lepton scattering off an unpolarized proton target at the Electron-Ion Collider. These asymmetries provide a means to observe transversely polarized quarks, which arise exclusively from the interference between the dipole and the Standard Model interactions, thereby depending linearly on the dipole couplings. We demonstrate that this novel approach can enhance current constraints on light-quark dipole operators by an order of magnitude, free from contamination of other new physics effects. Furthermore, it allows for a simultaneous determination of both the real and imaginary parts of the dipole couplings, offering a new avenue for investigating potential CP-violating effects at high energies.

dihadron fragmentation↗
DOE OSTI2024

Tension-compression asymmetry in superelasticity of SrNi 2 P 2 single crystals and the influence of low temperatures

ThCr 2 Si 2 -type intermetallic compounds are known to exhibit superelasticity associated with structural transitions through lattice collapse and expansion. These transitions occur via the formation and breaking of Si-type bonds, respectively, under uniaxial loading along the [0 0 1] direction. Unlike most ThCr 2 Si 2 -type intermetallic compounds, which have either an uncollapsed tetragonal structure or a collapsed tetragonal structure, SrNi 2 P 2 possesses a third type of collapsed structured: a one-third orthorhombic structure, for which one expects the occurrence of unique structural transitions and superelastic behavior. In this study, uniaxial compression and tension tests were conducted on micron-sized SrNi 2 P 2 single crystalline columns at room temperature, 200 K, and 100 K, to investigate the influence of loading direction and temperature on the superelasticity of SrNi 2 P 2 . Experimental data and density functional theory calculations revealed the presence of tension-compression asymmetry in the structural transitions and superelasticity, as well as an asymmetry in their temperature dependence, due to the opposite superelastic process associated with compression (forming P-P bonds) and tension (breaking P-P bonds). Additionally, following thermodynamics, the observations suggest that this asymmetric superelasticity could lead to an opposite elastocaloric effect between compression and tension, which could be beneficial potentially in obtaining large temperature changes compared to conventional superelastic solids that show the same elastocaloric effect regardless of loading direction. Furthermore, these results provide an important fundamental insight into the structural transitions, superelasticity processes, and potential elastocaloric effects in SrNi 2 P 2 .

36 MATERIALS SCIENCE↗
DOE OSTI2023

ECCE sensitivity studies for single hadron transverse single spin asymmetry measurements

Here, we performed feasibility studies for various single transverse spin measurements that are related to the Sivers effect, transversity and the tensor charge, and the Collins fragmentation function. The processes studied include semi-inclusive deep inelastic scattering (SIDIS) where single hadrons (pions and kaons) were detected in addition to the scattered DIS lepton. The data were obtained in pythia6 and geant4 simulated e+p collisions at 18 GeV on 275 GeV, 18 on 100, 10 on 100, and 5 on 41 that use the ECCE detector configuration. Typical DIS kinematics were selected, most notably Q 2 >1 GeV 2 , and cover the x range from 10 -4 to 1. The single spin asymmetries were extracted as a function of x and Q 2 , as well as the semi-inclusive variables z, which corresponds to the momentum fraction the detected hadron carries relative to the struck parton, and P T , which corresponds to the transverse momentum of the detected hadron relative to the virtual photon. They are obtained in azimuthal moments in combinations of the azimuthal angles of the hadron transverse momentum and transverse spin of the nucleon relative to the lepton scattering plane. In order to extract asymmetries, the initially unpolarized MonteCarlo was re-weighted in the true kinematic variables, hadron types and parton flavors based on global fits of fixed target SIDIS experiments and e + e – annihilation data. The expected statistical precision of such measurements is extrapolated to 10 fb –1 and potential systematic uncertainties are approximated given the deviations between true and reconstructed yields. Similar neutron information is obtained by comparing the ECCE e+p pseudo-data with the same from the EIC Yellow Report and scaling the corresponding Yellow Report e+ 3 He pseudo-data uncertainties accordingly. The impact on the knowledge of the Sivers functions, transversity and tensor charges, and the Collins function has then been evaluated in the same phenomenological extractions as in the Yellow Report. Finally, the impact is found to be comparable to that obtained with the parametrized Yellow Report detector and shows that the ECCE detector configuration can fulfill the physics goals on these quantities.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2022

Target normal single-spin asymmetry in inclusive electron-nucleon scattering with two-photon exchange: Analysis using 1/$N_c$ expansion

We calculate the target normal single-spin asymmetry caused by two-photon exchange in inclusive electron-nucleon scattering in the resonance region. Our analysis uses the 1/$N_c$ expansion of low-energy QCD and combines $\textit{N}$ and Δ intermediate and final states using the contracted $\textit{SU}$(4) spin-flavor symmetry. The normal spin asymmetry obtained in leading-order accuracy in 1/$N_c$ has magnitude ~10 -2 and different sign in $\textit{ep}$ and $\textit{en}$ scattering. It can be measured in electron scattering at lab energies ~0.5-1.5 GeV and provides a clean probe of two-photon exchange dynamics.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2023

Measurement of the charge asymmetry in top-quark pair production in association with a photon with the ATLAS experiment

A measurement of the charge asymmetry in top-quark pair ($t\bar{t}$) production in association with a photon is presented. The measurement is performed in the single-lepton $t\bar{t}$ decay channel using proton–proton collision data collected with the ATLAS detector at the Large Hadron Collider at CERN at a centre-of-mass-energy of 13 TeV during the years 2015–2018, corresponding to an integrated luminosity of 139 fb –1 . The charge asymmetry is obtained from the distribution of the difference of the absolute rapidities of the top quark and antiquark using a profile likelihood unfolding approach. It is measured to be A C =–0.003 ± 0.029 in agreement with the Standard Model expectation.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Beam Spin Asymmetry Measurements of Deeply Virtual $π$ 0 Production with CLAS12

The new experimental measurements of beam spin asymmetry were performed for the deeply virtual exclusive $π$ 0 production in a wide kinematic region with the photon virtualities $Q$ 2 up to 8 GeV 2 and the Bjorken scaling variable $x$ $B$ in the valence regime. The data were collected by the CE BAF Large Acceptance Spectrometer (CLAS12) at Jefferson Lab with longitudinally polarized 10.6 GeV electrons scattered on an unpolarized liquid-hydrogen target. Sizable asymmetry values indicate a substantial contribution from transverse virtual photon amplitudes to the polarized structure functions. The interpretation of these measurements in terms of the Generalized Parton Distributions (GPDs) demonstrates their sensitivity to the chiral-odd GPD $\overline{E}$ $T$ , which contains information on quark transverse spin densities in unpolarized and polarized nucleons and provides access to the proton’s transverse anomalous magnetic moment. Additionally, the data were compared to a theoretical model based on a Regge formalism that was extended to the high photon virtualities.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2026

Quasielastic $\overrightarrow{^{3}He}$ $(\overrightarrow{e},e′)$ asymmetry in the threshold region with a longitudinally polarized target

We report on the measurements of the double-spin asymmetry from electron- 3 He scattering in the threshold region of two- and three-body breakup of 3 He for 4-momentum transfer values of 0.1 and 0.2 (GeV/c) 2 . The measurement was done at Jefferson Lab using a polarized 3 He target with its spin aligned parallel to the beam direction. This asymmetry is sensitive to a combination of spin-dependent response functions not previously measured and may highlight differences in two body forces, meson-exchange currents and final-state interactions. The results of this measurement serve as a test of our understanding of few-body systems. When compared with calculations from plane wave impulse approximation and Faddeev calculations, we found that the latter, which use modern nuclear potentials and prescriptions for meson-exchange currents, demonstrate an overall good agreement with data.

Few-body nuclei↗
DOE OSTI2026

Single spin asymmetry in e+p → e′ +B↑ +X

We study an exotic type of single spin asymmetry in unpolarized electron-proton scattering, in which the outgoing electron momentum exhibits a left-right asymmetry relative to the transverse spin of the leading baryon B in the target fragmentation region. We lay out two theoretical frameworks for describing this effect: The twist-three fracture function at high-Q2 and the spin-dependent odderon in the high energy limit.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗