Alternative evaluations of halos in nuclei

Data for the scattering of 6He, 8He, 9Li, and 11Li from hydrogen are analyzed within a fully microscopic folding model of proton-nucleus scattering. Current data suggest that of these only 11Li has a noticeable halo. For 6He, we have also analysed the complementary reaction 6Li(gamma,pi)6He(gs). The available data for that reaction support the hypothesis that 6He may not be a halo nucleus. However, those data are scarce and there is clearly a need for more to elicit the microscopic structure of 6He.Comment: 18 pages, 8 figures (added 4 figures), added reference. Version accepted for publication in Phys. Rev.

Tidal gravity observations in Eastern Siberia and along the Atlantic coast of France

Tidal gravity observations had been performed during more than 2 years (April 2001-September 2003) in Eastern Siberia with the LCR402. Simultaneously the gravimeter LCR1006 was recording in Chize Observatory, not far from La Rochelle, in France. In France the station Chize is the third of a network extending from "Aquitaine" (Menesplet) to Brittany (Mordelles). All stations are located far enough from the sea to avoid very local effects in ocean tide loading. The main goal of the project was to compare the observed tidal parameters with the modelled ones, using different ocean models, i.e.: SCW80, CSR3, FES95, ORI96, CSR4, FES02, GOT00 and NAO99. A general conclusion is that the predictions using all the ocean tide models are in agreement within 0.2% for the area of Khabarovsk (Eastern Siberia). We may thus consider that a mean of all the oceanic models will have a precision better than 0. 1 %. It would thus be very difficult to improve the models using tidal gravity observations in this area. However, for the Atlantic coast of France the tidal parameters derived from different ocean tide models can disagree at the level of 3%. The observed results are close to the predictions derived from CSR3, CSR4 and FES02 models

Transcontinental tidal transect: European Atlantic coast-Southern Siberia-Russian Pacific coast

The paper presents results of measurements with digital tidal LaCoste-Romberg gravimeters on the European Atlantic coast-Southern Siberia-Russian Pacific coast transect in 1995-2005. The transect includes four West European (Chize, Menesplet, Mordelles, and Wikle), two South Siberian (Klyuchi and Talaya), and two Far Eastern (Zabakalskoe and Yuzhno-Sakhalinsk) stations. Gravimetric measurements at the Talaya station (SW Baikal rift zone) are supplemented by long-term laser extensometer observations. The position of the stations within the rectangle (45°-55°N, 0.4°-142°E) allows one to assess existing tidal strain models (WD93 and DDW99) and various ocean tide models (SCW80, CSR3, FES95, ORI96, CSR4, FES02, GOT00, NAO99, and TPX06). Data of intracontinental stations (with a small ocean effect at distances of 2000-3000 km) agree well with the DDW99 tidal strain model (with regard to the mantle viscosity). The uncertainty of digital tidal gravity measurements is 0.25%. Results of laser extensometer measurements are at the same accuracy level. Then, the Love and Shida numbers calculated at midlatitudes of the intracontinental zone of Eurasia from combined data are h = 0.6077 +/- 0.0008, k = 0.3014 +/- 0.0001, and l = 0.0839 +/- 0.0001. The analysis of results of Pacific and Atlantic stations located at distances of 30-300 km from the ocean showed that the FES02, CSR4, GOT00, NAO99, and TPX06 ocean tide models are preferable