The initial beam diameter (4 mm) was reduced to 80 Î¼m. However, this spatial resolution is not high enough. To focus beam more, a small positron source should be fabricated. In this work, we developed a positron microbeam by a small source, a solid neon moderator, magnetic lenses and a SEM optics. In addition, a beam pulsing system was also developed which allows the positron annihilation lifetime spectroscopy (PALS) measurement.
The first American to orbit the Earth, John Glenn made history again when, at the age of 77, he became the oldest person to travel in space. But before he was nationally recognized as a hero, he had put his life on the line for his country many times.
John Glenn, First American To Orbit Earth, Dies At 95. John Glenn, a freckle-faced son of Ohio who was hailed as a national hero and a symbol of the space age as the first American to orbit Earth, then became a national political figure for 24 years in the Senate, died on Thursday in Columbus, Ohio. He was 95. His death was announced on Twitter by Gov. John Kasich of Ohio.