doi: 10.1086/132168pmid: N/A
This paper is reproduced from Publ. Astron. Soc. Pac., Vol. 37, p. 307 -318 (1925) to celebrate the centenary of the Publications. See also 004.048.
doi: 10.1086/132169pmid: N/A
This is one of the review papers celebrating the centenary of the Astronomical Society of the Pacific. Trumpler describes his invention of a classification system of H-R diagrams for a sample of open clusters in the Galaxy. Trumpler's 1925 paper with its classification system was an important initial step in developing the ideas of stellar evolution that culminated in the 1950s. See also 004.047.
doi: 10.1086/132170pmid: N/A
This paper is reproduced from Publ. Astron. Soc. Pac., Vol. 42, p. 214 - 226 (1930) to celebrate the centenary of the Publications. See also 004.050.
doi: 10.1086/132171pmid: N/A
This is one of the review papers celebrating the centenary of the Astronomical Society of the Pacific. The author discusses the content of Trumpler's paper, presents the influence on subsequent astronomical development and gives a few highlights of the developments since Trumpler's time. See also 004.049.
Vandenberg, Don A.; Smith, Graeme H.
doi: 10.1086/132172pmid: N/A
The authors have attempted to explore the hypothesis that differences in the depth of stellar interior mixing can account for the star-to-star differences in C and N abundances that are commonly observed within globular clusters. The canonical first dredge-up episode predicted by standard stellar models does not reproduce the nitrogen enhancements seen among the CN-enriched giants in most globular clusters. As a result, stellar models in which the envelopes have been artificially mixed to some arbitrary depth have been used in an attempt to identify possible epochs during the evolution of a cluster star during which deep mixing might be able to produce the observed abundance patterns.
Pilachowski, Catherine A.; Hobbs, L. M.
doi: 10.1086/132173pmid: N/A
The abundance of lithium has been determined for an additional six F stars in the intermediate-age galactic cluster NGC 752. These new observations confirm and better define the dip in the abundance of lithium among the mid-F stars which has been reported in younger star clusters.
doi: 10.1086/132174pmid: N/A
Radial velocities are derived from 76 medium-resolution spectra of 57 stars in the old open clusters NGC 2158, NGC 6791, NGC 6882/5, NGC 6939, and NGC 6940. The mean cluster radial velocities are determined to ⪉3 km s-1. Cluster membership is discussed and the results are compared to previous investigations.
doi: 10.1086/132175pmid: N/A
Among galaxies with redshifts ≤ 500 km s-1^ spirals are found to have random orientations, whereas irregulars exhibit a highly significant excess of objects with 30deg^ <i< 60deg^. This effect may be explained by assuming that irregular galaxies are not well represented by spheroids of revolution with an intrinsic flattening of 0.2, which is the value that is generally used to calculate the inclinations of such objects. The observations suggest that typical dwarf irregular galaxies are triaxial objects with axis ratios of 1.0 : 0.9 : 0.4.
doi: 10.1086/132176pmid: N/A
A survey of optically-visible dust clouds is made on a set of CTIO 4-m telescope plates of the LMC, covering 14 fields in different parts of the Cloud. The dark nebulae cataloged are, on the average, a factor of two smaller than those of the previous survey, a result of the larger scale and deeper limit of the new plate material. The 146 dark nebulae have a mean dimension of 26 pc and a mean Lynds opacity class of 2.6. Although there is a good general agreement in position with CO clouds (Cohen et al. 1987), there are areas with CO emission and no dust clouds, as well as vice versa.
Griffin, R. F.; Beavers, W. I.; Eitter, J. J.
doi: 10.1086/132177pmid: N/A
The authors show that 35 Com A (=HR 4894, HD 112033, the brightest component of ADS 8659) is a spectroscopic binary. It has a very eccentric orbit and a period of 8 years. There is no significance in the anomalously large mass that has sometimes been attributed to the system.
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