Sometime early in the next century the miniaturization of conventional electronic devices will grind to a halt. The inexorable progress that has seen the number of transistors on a single silicon chip increase by a factor of 16 000 over the past 24 years cannot continue indefinitely. A combination of reasons – cost, technology and […]
In an ingenious series of experiments the Göttingen team squirted liquid helium through a fine nozzle to create drops containing about 104 atoms at a temperature of 0.1 K. The team used laser spectroscopy to probe the rotational behaviour of oxygen carbon sulphide (OCS) molecules that had been dissolved in the helium. The experiment was […]
The efficiency with which light of one frequency is converted into a higher frequency in a nonlinear material increases when both frequencies travel through the material with the same phase velocity. This condition is known as phase matching. This technique is traditionally used in solids, but few solids are transparent at extreme ultraviolet and soft […]
Terebey and colleagues believe that the new planet was in orbit around two stars – TMR-1A and -1B – before it was ejected by a gravitational slingshot mechanism. The planet then created a “light tube” as it burrowed through the dust clouds surrounding the binary star system. It was this light tube that attracted attention […]
The VLT uses active optics to reduce the effect of atmospheric turbulence on observations. In this technique the optical quality of a star is continually monitored against a reference star and the surface of the mirror adjusted to ensure that the image remains focused at all times. Similar adjustments are made to counteract the effects […]
Brookhaven will produce germanium-68, which is used to calibrate positron emission tomography (PET) scanners, and copper-67 for diagnostic and research purposes. It will also make strontium-82: this isotope decays into rubidium-82, which is widely used in studies of the heart. The recently upgraded Brookhaven Linac Isotope Producer (BLIP) accelerator will be used to produce the […]
Sharif claimed on national television that the country had exploded five nuclear devices. Presently only two explosions -with 12 and 25 kiloton yields – have been confirmed by seismic monitoring stations. The other three tests are suspected to have been subkiloton devices. “Had India been penalised for its actions we would not have conducted these […]
Teller played important roles in the development of the atomic and hydrogen bomb. In 1939 he chauffeured another Hungarian physicist, Leó Szilárd, to a meeting with Albert Einstein. Szilárd persuaded Einstein to write to President Roosevelt about the need to develop an atomic bomb. This letter led to the establishment of US atomic programme. While […]
The Chalk River lab is owned by Atomic Energy of Canada (AECL) and supplies molybdenum-99, iodine-125, iodine-131 and xenon-133 to MDS Nordion for the manufacture of radiopharmaceuticals. A derivative of molybdenum-99 – technetium 99 – is used in 90 per cent of hospital radiopharmaceutical medical procedures. This amounts to over 15 million medical procedures per […]
The deal was hatched in discussions between Ellis Rubinstein, editor of Science , and Zhou Guangzhao, president of the Chinese Association for Science and Technology. A group of Chinese funding agencies have joined forces to pay for the deal. China is seen by many publishers as an expanding market over the next few years. The […]
