화학공학소재연구정보센터
Science, Vol.341, No.6142, 150-153, 2013
Voyager 1 Observes Low-Energy Galactic Cosmic Rays in a Region Depleted of Heliospheric Ions
On 25 August 2012, Voyager 1 was at 122 astronomical units when the steady intensity of low-energy ions it had observed for the previous 6 years suddenly dropped for a third time and soon completely disappeared as the ions streamed away into interstellar space. Although the magnetic field observations indicate that Voyager 1 remained inside the heliosphere, the intensity of cosmic ray nuclei from outside the heliosphere abruptly increased. We report the spectra of galactic cosmic rays down to similar to 3 x 10(6) electron volts per nucleon, revealing H and He energy spectra with broad peaks from 10 x 10(6) to 40 x 10(6) electron volts per nucleon and an increasing galactic cosmic-ray electron intensity down to similar to 10 x 10(6) electron volts.