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The longitudinal or transverse spin transfer to Lambda and anti-Lambda hyperons in polarized proton-proton collisions is expected to be sensitive to the helicity or transversity distributions of strange and anti-strange quarks of the proton, and to the corresponding polarized fragmentation function. We report the first measurement of the transverse spin transfer to $��$ and $\bar ��$ along the polarization direction of the fragmenting quark, $D_{TT}$, in transversely polarized proton-proton collisions at 200 GeV with the STAR experiment at RHIC. The data correspond to an integrated luminosity of 18 pb$^{-1}$, and cover a kinematic range of |$��$|< 1.2 and transverse momentum $p_T$ up to 8 GeV/c. We also report an improved measurement of the longitudinal spin transfer $D_{LL}$ to $��$ and $\bar ��$ with $p_T$ up to 6 GeV/c, using data with about twelve times larger figure-of-merit than the previously published STAR results. The prospects of hyperon polarization measurements in the forward pseudo-rapidity region (2.5, 5 pages, 2 figures, proceedings for 23rd International Spin Physics Symposium (SPIN2018)

An excellent Lonicera edulis strain, L1-8 that was bred by Northeast Institute of Geography and Agro-ecology, Chinese Academy of Sciences, was used as material in this research. The axillary buds of its dormant branches were used as explants. A four-factor and four-level orthogonal test was designed in order to choose the best differentiation medium for providing the technical support of Lonicera edulis micropropagation. The results showed that the culture medium and concentration of 6-BA were the main factors, and the best differentiation condition was MS culture medium containing 2.0 mg · L−1 6-BA, 0.3 mg · L−1 IBA and 1.5 mg · L−1 GA3.

The regulating axillary branch gene was cloned and named as CsCCD7. Using a series bioinformatic computer softwares, database and online programes, CsCCD7 nucleotide sequence and CsCCD7 amino acid sequence were analyzed and CsCCD7 function was predicted. The results showed that CsCCD7 cDNA full length sequence was 2 136 bp, and included a 1 665 bp ORF which encoded a 554 AA protein; there were 32 kinds of cis-acting regulating element in 2 136 bp cDNA sequence; CsCCD7 was an unstable protein (the unstable coefficient: 40.77), including many phosphorylation sites related with CsCCD7 function; CsCCD7 had no transmembrane domain, and its subcellular localization was in chloroplast. CsCCD7 secondary structure contained four conformations including α-helix, β-sheet, β-turn and random coil. CsCCD7 protein had no signal peptide, so was non-secretory protein and hydrophilicity protein (grand average of hydropathicity: −0.401). Both CsCCD7 secondary and tertiary structure prediction results showed that it was classified as carotenoid oxygenase family. Phylogenetic tree drew by Geneious showed that CsCCD7 was more closely related to AtCCD7 than any other Arabidopsis CCD protein.

We calculate the contribution of vector meson dominance to deeply inelastic lepton-nucleon scattering in the kinematic region of the HERMES experiment. The results obtained show that this contribution is quite significant. Together with the fact that there exist very striking left-right asymmetries for hadrons produced in single-spin hadron-hadron collisions, these results imply that the single-spin azimuthal asymmetry observed by HERMES cannot be simply regarded as a pure fragmentation effect.

We report our measurement on longitudinal spin transfer, D_LL, from high energy polarized protons to $\Lambda$ and $\bar{\Lambda}$ hyperons in proton-proton collisions at $\sqrt{s} = 200 GeV$ with the STAR detector at RHIC. The current measurements cover $\Lambda$, $\bar\Lambda$ pseudorapidity $|\eta| < 1.2$ and transverse momenta $p_T$ up to $4GeV/c$ using the data taken in 2005. The longitudinal spin transfer is found to be D_LL= -0.03\pm 0.13 (stat) \pm 0.04(syst)$ for inclusive $\Lambda$ and $D_{LL} = -0.12 \pm 0.08(stat) \pm 0.03(syst)$ for inclusive $\bar{\Lambda}$ hyperons with $ = 0.5$ and $ = 3.7 GeV/c$. The prospects with 2009 data and the future measurements are also given., Comment: 6 pages, 3 figures, presentation at the SPIN2010 International Symposium, Juelich (Germany), Sep. 27-Oct. 2, 2010

We report our measurement on longitudinal spin transfer, $D_{LL}$, from high energy polarized protons to $��$ and $\bar��$ hyperons in proton-proton collisions at $\sqrt{s} = 200GeV$ with the STAR detector at RHIC. The measurements cover $��$, $\bar��$ pseudorapidity $|��| < 1.2$ and transverse momenta $p_T$ up to $4GeV/c$. The longitudinal spin transfer is found to be $D_{LL}= -0.03\pm 0.13(stat) \pm 0.04(syst)$ for inclusive $��$ and $D_{LL} = -0.12 \pm 0.08(stat) \pm 0.03(syst)$ for inclusive $\bar��$ hyperons with $ = 0.5$ and $ = 3.7GeV/c$. The prospect on transverse spin transfer measurement is also given., Talk given at XIII workshop on high energy spin physics (DSPIN-09), Dubna, Russia, 1-5 September 2009

Using the same method as that used in $e^+e^-$ annihilation and lepton-nucleon deep-inelastic scattering, we calculate the spin alignment of vector mesons with high transverse momenta in high energy $pp$ collisions with one longitudinally polarized beam. We present the results obtained at RHIC energies. We also study the spin alignment of such vector mesons in the case of a transversely polarized proton beam and present its relation to the transversity distribution in the nucleon. Numerical results obtained using simple models for the transversity distributions are also given. These results show that there exist significant spin alignment in both cases, and they can be measured in experiments such as those at RHIC.

We argue that spin alignment of the vector mesons observed in unpolarized hadron-hadron collisions is closely related to the single spin left-right asymmetry observed in transversely polarized hadron-hadron collisions. We present the numerical results obtained from the type of spin-correlation imposed by the existence of the single-spin left-right asymmetries. We compare the results with the available data and make predictions for future experiments., Comment: submitted to Phys. Rev . D

We extend the calculations of the spin alignments of vector mesons in $e^+e^-$ annihilation in a recent Rapid Communication to deeply inelastic lepton-nucleon scatterings. We present the results for different mesons in the current fragmentation regions of $\mu^- N$$ \to$$ \mu^- VX$ at high energies and $\nu_\mu N $$\to$$ \mu^- VX$ at both high and low energies. We also present the predictions for $\nu_\mu N$$ \to$$ \mu^- VX$ at NOMAD energies in the target fragmentation region using a valence quark model., Comment: 4 pages, 6 figures; to appear in Phys. Rev. D

We apply the picture proposed in a recent Letter for transverse hyperon polarization in unpolarized hadron-hadron collisions to the exclusive process ${e}^{\ensuremath{-}}\stackrel{\ensuremath{\rightarrow}}{p}{e}^{\ensuremath{-}}\mathrm{HK}$ such as ${e}^{\ensuremath{-}}\stackrel{\ensuremath{\rightarrow}}{p}{e}^{\ensuremath{-}}\ensuremath{\Lambda}{K}^{+},$ ${e}^{\ensuremath{-}}\stackrel{\ensuremath{\rightarrow}}{p}{e}^{\ensuremath{-}}{\ensuremath{\Sigma}}^{+}{K}^{0},$ or ${e}^{\ensuremath{-}}\stackrel{\ensuremath{\rightarrow}}{p}{e}^{\ensuremath{-}}{\ensuremath{\Sigma}}^{0}{K}^{+},$ or the similar process ${e}^{\ensuremath{-}}\stackrel{\ensuremath{\rightarrow}}{p}{e}^{\ensuremath{-}}n{\ensuremath{\pi}}^{+}$ with longitudinally polarized electron beams. We present the predictions for the longitudinal polarizations of the hyperons or neutron in these reactions, which can be used as further tests of the picture.

We calculate the longitudinal polarizations of hyperons in high $p_\perp$ jets in $pp$ collisions in which one of the protons is longitudinally polarized at RHIC energies using different models for the spin transfer in fragmentation process. The results show that the measurements of these polarizations can be used to study the spin transfer in high energy fragmentation processes in general and to test the different models in particular. Our results show especially that the magnitude of the polarization of $\Lambda$ is rather small whereas that of $\Sigma^+$ is considerably larger in the large rapidity region. The differences between the results from different pictures for $\Sigma^+$ polarizations is also much larger. Hence, the measurement of $\Sigma^+$ polarization should be more effective to distinguish between different models especially the SU(6) or the DIS picture for spin transfer in fragmentation processes., Comment: 26 pages, 11 figures; to appear in Phys. Rev. D

We apply the picture proposed in a recent Letter for transverse hyperon polarization in unpolarized hadron-hadron collisions to the exclusive process e^-p --> e^-HK such as e^-p-->e^-��K^+, e^-p --> e^-��^+ K^0, or e^-p--> e^-��^0 K^+, or the similar process e^-p\to e^-n��^+ with longitudinally polarized electron beams. We present the predictions for the longitudinal polarizations of the hyperons or neutron in these reactions, which can be used as further tests of the picture., 15 pages, 2 figures. submitted to Phys. Rev. D