One-dimensional beam ordering of protons in a storage ring

The ordering of protons has been observed at a new storage ring, S-LSR, at Kyoto University. Abrupt jumps in the momentum spread and the Schottky noise power were observed for protons for the first time at a particle number of approximately 2000, upon applying electron cooling with electron currents of 25, 50, and 100 mA. The transition temperature was 0.17 and 1 meV in the longitudinal and transverse directions, respectively. The transverse temperature of the proton beam was much below that of electrons at the transition, which played an essential role in the ordering of protons.     

Role of nickel and manganese in recovery of resistivity in iron-based alloys after low-temperature proton irradiation

This study investigates the recovery of electric resistivity in pure iron, Fe–0.6Ni and Fe–1.5Mn as related to isochronal annealing following 1 MeV proton irradiation at lower temperature than 70 K, focusing on the relationship between solute atoms and irradiation defects. Both nickel and manganese prevent stage I_D recovery, which corresponds to correlated recombination. Stage II recovery is also changed by the addition of a solute, which corresponds to the migration of small interstitial clusters. In both pure iron and Fe–0.6Ni, no evident difference was observed in the stage III region, which corresponds to the migration of vacancies. In contrast, two substages appeared in the Fe–1.5Mn at a higher temperature than stage III_B appeared in pure iron. These substages are considered to represent the release of irradiation-induced defects, which was trapped by manganese.     

基于散射实验极化靶的2.5T/1.3K的动态核极化(DNP)系统的开发

动态核极化法(Dynamic Nuclear Polarization, DNP)是利用热平衡下的电子在磁场中的高自旋极化率转移到原子核自旋的技术,从而极大的提高原子核自旋极化率。多种动态极化靶材料已广泛的用于自旋物理散射实验。本文介绍一种简单实用,共同开发的日本山形大学DNP系统,包括超导磁场,氦4蒸发恒冷器,微波系统以及NMR核磁共振检测系统,测得中子靶材料氘带丁醇(D-butanol)中氘核的极化率在2.5T/1.3K达到+6.5%。     

Annihilation rates of positrons on aromatic molecules

We have measured positron annihilation rates for a selection of hydrocarbon molecules based on six carbon atoms, including substituted benzenes. These measurements illustrate the importance of molecular symmetry in determining the annihilation rate.     

Inclusive η production at high pT at the ISR

The inclusive η production cross section at the CERN ISR has been measured for p_T values of up to 11 GeV/c. We find that the $\text{η}\text{π}{}^0$ cross-section ratio has an average value of 0.55 ± 0.07 and varies little with p_T.     

QCLDB—Quantum chemistry literature data base—a trial

A brief account of a quantum chemistry literature data base (QCLDB ) is described, which contains the key information of about 2000 papers of ab initio calculations of atoms and molecules published in 1977–1979. The QCLDB is stored in a computer and can be sorted and rearranged into author and substance indices. Selection of the items for each paper in a computer-readable data base is discussed.     

Hydrogenation of olefins by π-arene ruthenium complexes : A role of π-arene ligand in catalytic activity

The divalent ruthenium complexes bearing benzene, mesitylene triphenylbenzene as a π-ligand were prepared and their catalytic activity for olefin hydrogenation was examined. They showed activity in the presence of a small amount of base. Particularly, the complex with triphenylbenzene was found to have extremely high activity. Discussion here is on a role of a π-arene ligand in the activity.     

First Measurement of the Gerasimov-Drell-Hearn Sum Rule for 1H from 0.7 to 1.8 GeV at ELSA

To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out with a 4pi detection system, a circularly polarized tagged photon beam, and a frozen spin polarized proton target. The contribution to the GDH sum rule in this photon energy range is [49.9+/-2.4(stat)+/-2.2(syst)] microb.     

Beam-polarization asymmetries for the p(gamma-->, K+)Lambda and p(gamma-->, K+)Sigma(0) reactions for E(gamma)=1.5-2.4 GeV

Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6相似文献