Publications of the Astronomical Society of the Pacific

Motz, Lloyd

doi: 10.1086/129319pmid: N/A

The general dffferential equations for the structure of stars are developed. These are then applied to the analysis of the structure of chemically homogeneous main-sequence stars. Some general deductions are made about the dependence of the slope of the main sequence on the energy generating cycle. The variation in the position of the main sequence with chemical composition is also discussed. Key words: stellar structure - stellar models

Bessell, M. S.

doi: 10.1086/129320pmid: N/A

Hydrogen line profiles and K-line strengths for F 131 and F 90 probable members of M67 indicate a metal deficiency of a factor of 1.7 relative to the sun and a reddening for these two stars of about E(b - y) = 0.05. Key words: stars - abundance of elements - star clusters

Snow, Theodore P.; Wallerstein, George

doi: 10.1086/129321pmid: N/A

We have searched for difflise features at AX4430, 5780, 5796, and 6613 in the spectra of 17 stars which show infrared excesses or other grounds for believing that they have dusty envelopes. In no case could we identif' bands that may be ascribed to the circumstellar envelope. We conclude that the grains in circumstellar envelopes are not identical with the grains in the general interstellar medium. Key words: stars - interstellar features - infrared objects

Feltz, K. A.

doi: 10.1086/129322pmid: N/A

Color excesses are obtained for 182 B-, A-, and F-type stars within about 20 degrees of the north galactic pole with the aid of BV, uvby , and (khg) photometry. The average value of the reddening in the vicinity of the pole is found to be 0"?0O0::::: 0.002. Some structure of the interstellar medium is suggested by the data, but, for the most part, the amount of dust in the direction of the NCP is not sufficient to produce measurable reddening. Key words: interstellar reddening - noi{ih galactic pole - photometry

Croft, S. K.; McNamara, D. H.; Feltz, Kent A.

doi: 10.1086/129323pmid: N/A

Two photometric (khg) indices have been measured for 42 F, C, and K luminosity class V stars and Uranus. The indices correlate well with the (B- V) and (U- B) values of the stars. The (khg) indices of Uranus are used to derive (B- V) and (U- B) values for the sun. The results are (B-V)0 = :::: (p.e.)and(U-B)0 = t 0"'007(p.e.). Key words: sun - stars - photometry

Hilditch, R. W.

doi: 10.1086/129324pmid: N/A

Spectrographic observations of this eclipsing binary system are presented for the first time. It is shown that both components are main-sequence stars which conform to the theoretical calculations of Iben (1967). Key words: eclipsing binary - radial velocities - orbital elements

Swings, J. P.; Allen, D. A.

doi: 10.1086/129325pmid: N/A

The majority of symbiotic and VV Cephei stars have near infrared continua closely resembling those of late-type stars. Evidence for weak infrared excesses has been found in the three stars RY Sct, W Cep, and U Lac. RX Pup and V1O16 Cyg exhibit very prominent infrared excesses which are attributable to thermal radiation from circumstellar dust. The "Bep" star MWC 56, whose spectrum shows Fe ii and [Fe ii] emission lines in the blue, possesses the absorption lines of a C or K component in the red. No substantial infrared excess is present. Key words: near-infrared photometry - symbiotic stars - VV Cephei stars

Fernie, J. D.

doi: 10.1086/129326pmid: N/A

Occasional photometric observations of nine symbiotic stars during the years 1967-69 are reported. Key words: photometry - symbiotic stars

Jerzykiewicz, Mikolaj

doi: 10.1086/129327pmid: N/A

HD 90386 has been found to vary in yellow light with the period of about 0d0799 The light range is close to and appears to be slightly variable. The star is probably a member of the 8 Scuti group of variable stars. The constancy of light of 23 Sex has been confirmed. Key words: photoelectric photometry - variable stars

Sakurai, Kunitomo

doi: 10.1086/129328pmid: N/A

This paper discusses the relationships between some characteristics of microwave type IV radio bursts and solar cosmic ray protons of MeV energy. It is shown that the peak flux intensity of those bursts is almost linearly correlated with the MeV proton peak flux observed by satellites near the earth. The rise times of type IV microwave emissions are, however, independent of the proton peak fluxes. Using these results, discussion is given on the acceleration process and duration for both protons and electrons. Key words: solar radio activity - solar cosmic rays