Observation of the narrow state X(3872)-\u3e J/psi pi(+)pi(-) in (p)over-barp collisions at root s=1.96 TeV

We report the observation of a narrow state decaying into J/psipi(+)pi(-) and produced in 220 pb(-1) of (p) over barp collisions at roots=1.96 TeV in the CDF II experiment. We observe 730+/-90 decays. The mass is measured to be 3871.3+/-0.7(stat)+/-0.4(syst) MeV/c(2), with an observed width consistent with the detector resolution. This is in agreement with the recent observation by the Belle Collaboration of the X(3872) meson

Studies on high-Tc superconducting materials

Superconducting material of reproducible quality of the chemical composition y Ba2 'Cu3 07-6 this material has been prepared. Samples of have been characterised for the transition temperatures by electrical resistivity measurements.The crystallographic parameters of this material have been determined. Thin samples prepared by lapping showed an anomalous behaviour just before the transition

Dilametric studies on Ge-Sb-Se classes

Results of measurements of the thermal expansion coefficient from room temperature up to the softening temperature on several compositions of the Ge-Sb-Se glass system are reported. The a -T data for these glasses have two region A below Tg where a is essentially constant followed by a region B around Tg where a increases with temperature. In the region A the composition dependence is identical for the three families of glasses studied, with the a-composition data showing an angularity at the corresponding stoichiometric composition of each family, while changes in a of about eighty percent are seen for compositions across a family, the change in a over the stoichiometric compositions is about fifteen per cent .An expression of the form a=za,x, where a, and x, are the expansion coefficients and weight fractions respectively of the individual structural units is found to account satisfactorily for the a-composition data of these glasses.In the region B,A increases with temperature .The increase in a is greater and begins at about 30to40 degrees lower than Tg for the SE-RICH GLASSES AS COMPARED TO THE Ge-rich glasses,where the increase is less and begins at T

Dilatometric measurements on solids

Dilatometric studies are performed on glasses to arrive at13; the value of thermal expansion coefficient and its variation during glass transition. The study also gives the values of the glass transition temperature and the softening temperature the glass. A thermal dilatometer (Harrop Laboratory, USA) has been commissioned and used for dilatometric studies on solids. In this report the details of the experimental procedure and the data processing are outlined. Typical results of measurements on Ge-Sb-Se glasses are given

Preparation and characterisation of IR transmitting glasses

Glasses of the Ge-Sb-Se system are good transmitters of the13; infrared radiation over the 2 to 16 region. These glasses offer several advantages over the conventional germanium which is used in most IR systems. They are therefore good candidates for specific applications where germanium has some shortcomings. Different composition glasses of this system have been prepared and characterised based on their IR transmission and other physical and thermal properties. In this article, the method of preparation and part of the characterisation are briefly outlined