Interference Fragmentation in SIDIS, pp and e+e−

This review highlights some recent developments in the measurement of the transverse-spin–dependent Interference Fragmentation Functions and di-hadron correlations in semi-inclusive deep inelastic scattering and proton-proton scattering. The latter measurements can be used to extract transversity using measurements of the fragmentation function in e+e− annihilation. Di-hadron correlations have been measured in pp at PHENIX and lepton-proton and lepton-deuteron scattering at HERMES and COMPASS. The Interference Fragmentation Function has recently been measured at the Belle experiment. The emphasis of this article will be the Belle and PHENIX results, as these results are not presented in other contributions to this volume

Measurement of the branching fraction of B → D(∗)π`ν at Belle using hadronic tagging in fully reconstructed events

We report a measurement of the branching fraction of the decay B→D(∗)πℓν. The analysis uses 772×106 BB¯ pairs produced in e+e−→Υ(4S) data recorded by the Belle experiment at the KEKB asymmetric-energy e+e− collider. The tagging B meson in the decay is fully reconstructed in a hadronic decay mode. On the signal side, we reconstruct the decay B→D(∗)πℓν (ℓ=e,μ). The measured branching fractions are (B+→D−π+ℓ+ν) = [4.55 ± 0.27 (stat.) ± 0.39 (syst.)]×10−3, (B0→D¯0π−ℓ+ν) = [4.05 ± 0.36 (stat.) ± 0.41 (syst.)]×10−3, (B+→D∗−π+ℓ+ν) = [6.03 ± 0.43 (stat.) ± 0.38 (syst.)]×10−3, and (B0→D¯∗0π−ℓ+ν) = [6.46 ± 0.53 (stat.) ± 0.52 (syst.)]×10−3. These are in good agreement with the current world average values

Monitoring the Dutch Phytophtora infestans population for virulence against new R-genes

New possibilities offered by marker assisted breeding and GMO breeding have sparked renewed international efforts to breed for durable potato late blight resistance. Phytophthora infestans is however known for its adaptability, a trait confirmed by recent discoveries on the structure of the P. infestans genome. One of the possibilities to enhance the durability of newly introduced host resistance is to monitor the pathogen population for virulence to new R genes, prior to - and after their introduction. The late blight control strategy should be adapted accordingly. The Dutch P. infestans population was monitored during the growing seasons 2006 – 2008. P. infestans isolates were collected from blighted production fields and from bait fields in which R gene containing potato clones were grown without fungicide protection. A selection of the P. infestans isolates collected were characterized for virulence to a range of new R genes using a detached leaf bio-assay. Virulence for all single R genes tested was found. When we focus on R genes Rpi-blb1 and Rpi-blb2, no virulence was found in 2006. One Rpi-blb1 virulent isolate was found in 2007. Another 2007 isolate was found to be virulent to Rpi-blb2. Depending on the genetic background in which Rpi-blb1 was placed 13 or 21 isolates were virulent in 2008. Depending on the genetic background in which Rpi-blb2 was placed 4 or 11 isolates were virulent in 2008. One isolate was found to infect the stacked Rpi-blb1 and Rpi-blb2 resistance genes in a detached leaf assay. From these findings it is recommended that monitoring systems should be part of future potato late blight control strategies. The resulting information on the dynamics of virulence within the local P. infestans population can then be used to enhance the durability of newly introduced host resistanc

Dihadron fragmentation functions and their relevance for transverse spin studies

Dihadron fragmentation functions describe the probability that a quark fragments into two hadrons plus other undetected hadrons. In particular, the so-called interference fragmentation functions describe the azimuthal asymmetry of the dihadron distribution when the quark is transversely polarized. They can be used as tools to probe the quark transversity distribution in the nucleon. Recent studies on unpolarized and polarized dihadron fragmentation functions are presented, and we discuss their role in giving insights into transverse spin distributions.Comment: To appear in the proceedings of the 19th International Spin Physics Symposium, Sept 27 - Oct 2, 2010, Juelich, Germany. To be published in JPC