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Observations of Interstellar Reddening in Cygnus and Perseus1

Published online by Cambridge University Press:  08 February 2017

K Nandy*
Affiliation:
Royal Observatory Edinburgh, Scotland

Extract

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The Object of the Edinburgh Spectrophotometry Survey is to determine the interstellar extinction law as precisely as possible and to search for intrinsic variations in it. The observations have been extended to early type stars up to a limiting magnitude of 11ṃ0 in regions extending from lII = 50° to lII = 200°. The 16/24/60-inch Schmidt telescope of the Royal Observatory has been used in conjunction with an objective prism and grating. Spectra extend from λ = 3300 Å to λ = 9000 Å with a dispersion of 1000 Å/mm at Hγ. Since few stars fainter than 9m have been measured in earlier investigations, the present survey extends considerably the amount of information available.

In determining the extinction from a comparison of pairs of stars, one reddened and the other unreddened, one is faced by the problem of having to find two intrinsically similar stars in the same galactic region.

Type
Research Article
Copyright
Copyright © Kluwer Academic Publishers 1965

Footnotes

1

The contents of this paper were published previously in the Pub. Roy Obs Edinburgh vol. 3, 1964, p. 142, and vol. 5, 1965, p. 13.

References

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