Accession Number : AD0921479

Title :   Baxicon: An Efficient Fixed-Angle Nephelometer.

Descriptive Note : Final rept. 9 Apr 73-15 Feb 74,

Corporate Author : HSS INC BEDFORD MA

Personal Author(s) : Stewart, Harold S. ; Brouwer, Willem ; Shuler, Marion P.

Report Date : APR 1974

Pagination or Media Count : 61

Abstract : This report describes the work that was performed in three major areas during the contract period. These include: (1) a study of optical, electronic, aerodynamic and mechanical principles leading to the design concepts of an efficient fixed-angle nephelometer to measure the sum of molecular and aerosol scattering coefficients in three wavelength bands in the visible and near infrared by using the axicon principle in reverse to measure scattering at 55 deg from a projected beam of light, (2) the design and fabrication of such a nephelometer for balloon born observations and (3) the alignment and tests of the instrument. The nephelometer weighs twenty pounds and operates on 10 watts. The sensitivity of the nephelometer as built is limited by signals caused by undesired reflections and scattering of the modulated beam. These limiting signals add to those from the sample and are roughly equal to those which occur when the nephelometer is filled with nitrogen at atmospheric pressure. (Author)

Descriptors :   (*NEPHELOMETERS, AIRBORNE), (*AEROSOLS, LIGHT TRANSMISSION), (*MOLECULES, LIGHT SCATTERING), (*ATMOSPHERIC PHYSICS, RADIATION ABSORPTION), AIR, RADIATION ATTENUATION, INFRARED FILTERS, INCANDESCENT LAMPS, MIRRORS, BAFFLES, AERODYNAMIC CHARACTERISTICS, PHOTOMULTIPLIER TUBES, PHOTOSENSITIVITY, NEAR INFRARED RADIATION, VISIBILITY, FLOW FIELDS, WEIGHT, POWER, NITROGEN, BAROMETRIC PRESSURE, BALLOONS.

Subject Categories : Atmospheric Physics
      Physical Chemistry
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE