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Author Greenstein, J. L. ♦ Aller, L. H.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword PHYSICS ♦ ASTROPHYSICS ♦ BARIUM ♦ CARBON ♦ ELEMENTS ♦ EMISSION ♦ HYDROCARBONS ♦ HYDROGEN ♦ IONS ♦ IRON ♦ LINE BROADENING ♦ MEASURED VALUES ♦ METALS ♦ NICKEL ♦ PHOTOELECTRIC EFFECT ♦ PRODUCTION ♦ QUANTITY RATIO ♦ SPECTRA ♦ SPECTROSCOPY ♦ STARS ♦ SUN ♦ TEMPERATURE ♦ THERMONUCLEAR REACTIONS ♦ VELOCITY
Abstract : 9 ; : ) copic analyses were made of three G type and one A type subdwarfs. Because of the extreme weakness of the atomic lines, a large amount of observational material was collected for HD 19445 and HD 140283 which has the highest weight); HD 219517, a star with intermediate line strengths was treated less elaborately, as was the high-velocity A star BD 161517. A table of wavelengths and identifications is given for HD 19415; aquivalent widths are given for the stronger lines in all stars. The weakness of ionized metals makes it difflcult to determine the temperature spectroscopically. Consequently, temperatures were based on the U, B, V photoelectric colors or the scanning of the continuos spectra, with corrections for blanketing by the lines, made by Melbourne. Not all subdwarfs are identical in composition. The average abundance the metals, as compared with the sun was defficent by a factor of 40 in HD 19445, 100 in HD 140183, and 20 in HD 219617, whereas BD 161517 shows only small and uncertain deficiencies. The lines of CH were used to obtain an estimate of the carbon abundance, which was found to be very low in the G subdwarfs. There was some evidence for a greater than normal ratio of nickel/ iron. The mean relative abundances of the elements from carbon to barium for the three G subdwarfs showed some apparently real differences from solar values. The
ISSN 0004637X
Educational Use Research
Learning Resource Type Article
Publisher Date 1960-11-01
Publisher Department Univ. of Michigan Observatory, Ann Arbor
Journal Astrophysical Journal
Volume Number 5
Issue Number Suppl Ser
Organization Univ. of Michigan Observatory, Ann Arbor


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