ISSN:
1572-946X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract The microorganism model of interstellar grains is investigated by spectroscopy from the infrared (IR), visible to the ultraviolet (UV) wave regions.E. coli, yeast and spores ofBacillus subtilis exhibit absorption bands at λ=3.1 and 9.7 μm; they also exhibit several absorptions at 6∼8 μm which are in agreement with the observed IS extinction curves. To obtain the extinction curves in the visible and UV regions, dry films of microorganism are prepared on a MgF2 plate or synthesized quartz plate and their spectra measured. In the wavelength region 190∼400 nm, conventional spectrophotometers are adopted for the measurement. The extinction curve of the film ofE. coli is similar to the observed IS curve. For the wave-range 100〈λ〈400 nm, a vacuum UV spectrometer is adopted to avoid absorptions due to O2 in the atmosphere. The extinction spectra by this method are in agreement with the result obtained by the conventional method where comparison is possible. The extinction curves ofE. coli and yeast are such that they incrase towards the short wavelength and exhibit a peak at λ-190 nm, which is different from the well-known IS peak at λ=220 nm. It remains to be seen whether interstellar low temperatures (10∼40 K) can shift the peak position in the extinction curve of biochemical materials.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00656048
