Discovery of a Color-selected Quasar at z = 5.50

I show how the existing observational data on Local Group dwarf galaxies can be used to estimate the average star formation law during the first 3 Gyr of the history of the universe. I find that the observational data are consistent with the orthodox Schmidt law with a star formation efficiency of about 4% if the star formation is continuous (during the first 3 Gyr). The efficiency is proportionally higher if most of the gas in the dwarfs was consumed (and never replenished) in a short time interval well before the universe turned 3 Gyr.     

First Mass-resolved Measurement of High-Energy Cosmic-Ray Antiprotons

We report new results for the cosmic-ray antiproton-to-proton ratio from 3 to 50 GeV at the top of the atmosphere. These results represent the first measurements, on an event-by-event basis, of mass-resolved antiprotons above 18 GeV. The results were obtained with the NMSU-WIZARD/CAPRICE98 balloon-borne magnet spectrometer equipped with a gas-RICH (Ring-Imaging Cerenkov) counter and a silicon-tungsten imaging calorimeter. The RICH detector was the first ever flown that is capable of identifying charge-one particles at energies above 5 GeV. The spectrometer was flown on 1998 May 28-29 from Fort Sumner, New Mexico. The measured p&d1;/p ratio is in agreement with a pure secondary interstellar production.     

我国南方地区一次连续降雹过程的卫星云图分析

应用日本GMS卫星3小时一次的红外和可见光云图,结合常规气象资料对1983年4月26日开始的连续三天的降雹过程进行了中尺度分析,讨论了过程的天气特点和发生发展的物理条件以及各种天气系统、天气条件间的相互作用,及其对强对流天气发生发展的作用。