ABSORPTION MEASUREMENTS AT MORNING TWILIGHT,
Abstract
This paper describes the variation of absorption produced by nuclear air bursts during the transition period from night to day. For air bursts occurring some 15 to 30 minutes before sunrise at 100 km, the transition absorption characteristics are found to have the following consistent features: (1) absorption increases from the nighttime value when the solar zenith angle reaches about 100 degree; and (2) the transition from night to day occurs over a time period some 30 minutes longer than that calculated by a lumped parameter solution of the rate equations using only 02(-) negative ions and photodetachment. Data from three very similar bursts which occurred when the solar zenith angles were 96, 90, and 81 degrees are compared and are found to indicate the following characteristics: (1) the peak absorption reached at about 5 minutes following each of these similar bursts increased progressively with a decrease in the zenith angle at burst time; (2) the transient behavior for the 81-degree case was of a pure daytime nature, while the 90- and 96-degree cases indicated a night-day transition behavior, with the 96-degree case more marked in this regard. This feature is consistent with the results for the bursts occurring shortly before sunrise. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1966
- Accession Number
- AD0634830
Entities
People
- C. M. Crain
Organizations
- RAND Corporation