The brighter stars of astrophysical interest in the southern sky.

Bidelman, W. P.; MacConnell, D. J.

doi:10.1086/111475

Cited by 160 publications

(139 citation statements)

References 0 publications

Supporting

Mentioning

133

Contrasting

Order By: Relevance

“…Therefore, we classify HD 37824 as a K0 III star and conclude that it has a solar [Fe/ H] value. Our spectral type is in good agreement with the K1 III and K0 III classifications of Bidelman & MacConnell (1973) and Houk & Swift (1999), respectively.…”

Section: Orbitsupporting

confidence: 89%

“…The observations produced by satellites such as HEAO-1, Einstein, EXOSAT, the Extreme Ultraviolet Explorer (EUVE ), and ROSAT have led to optical identifications (e.g., Buckley et al 1987;Fleming et al 1989;Cutispoto et al 1991Cutispoto et al , 1999Tagliaferri et al 1994;Jeffries et al 1995;Neuhaüser et al 1997) of many chromospherically active stars. Here we discuss three stars discovered from objective-prism spectra (Bidelman & MacConnell 1973;Bidelman 1981). Although spectroscopic orbits have been determined previously for HD 37824, HD 181809, and HD 217188, our new results improve their orbital elements.…”

Section: Introductionmentioning

confidence: 60%

“…An IUE spectrum, however, showed no evidence of the F-type secondary star suggested by Bidelman & MacConnell (1973). Hall et al (1991) analyzed 11 years of V-band photometry, modeling the data with two major star spot groups.…”

Section: Photometric Observations and Reductionsmentioning

confidence: 99%

“…In particular, such active stars have been found in objective-prism surveys (e.g., Bidelman & MacConnell 1973;Bidelman 1981Bidelman , 1985 and more recently in the moderate-and high-resolution spectroscopic searches of Henry et al (1996) and Strassmeier et al (2000), respectively. Over the past several decades, satellite surveys at X-ray and ultraviolet wavelengths have provided another very effective way of finding active, late-type stars.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Chromospherically Active Stars. XXIV. The Giant, Single-lined Binaries HD 37824, HD 181809, and HD 217188

Fekel

Henry

2005

View full text Add to dashboard Cite

We have obtained spectroscopy and photometry of three chromospherically active, single-lined spectroscopic binaries, HD 37824 (V1149 Ori), HD 181809 (V4138 Sgr), and HD 217188 (AZ Psc). HD 37824 has a circular orbit with a period of 53.57 days. Its primary is a K0 III star, while the secondary is likely a G or K dwarf. HD 181809 has an orbit with a period of 13.04667 days and a low eccentricity of 0.040. The primary has a spectral type of K0 III-IV, and its secondary is probably an M dwarf. The orbit of HD 217188 has a period of 47.1209 days and a moderately high eccentricity of 0.470. The spectral type of the primary is K0 III, while the secondary is likely an M dwarf. All three systems are estimated to have near solar iron abundances. Photometric observations spanning 15-16 years for all three stars yield mean photometric periods of 53.12, 59.85, and 90.89 days for HD 37824, HD 181809, and HD 217188, respectively. Thus, HD 37824 is rotating synchronously with the orbital period, while HD 181809 and HD 217188 are both rotating considerably slower than synchronously. All three stars show longterm variations in mean brightness and photometric amplitude, but no correlations are observed between the seasonal mean brightness, photometric amplitude, and seasonal photometric period in any of the stars. No clear evidence for long-term periodic variations in any of these parameters is present. The circular orbit of HD 37824 and the synchronous rotation of its K giant argue that the star is in the core helium-burning phase of its evolution. The giant components of HD 181809 and HD 217188 are asynchronous rotators, and both systems have eccentric orbits. Thus, those two stars are likely first-ascent giants.

show abstract

Section: Orbitsupporting

confidence: 89%

Section: Introductionmentioning

confidence: 60%

Section: Photometric Observations and Reductionsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Chromospherically Active Stars. XXIV. The Giant, Single-lined Binaries HD 37824, HD 181809, and HD 217188

Fekel

Henry

2005

View full text Add to dashboard Cite

show abstract

“…The selection of stars was made on the basis of spectral type (F and early G), luminosity class (V-IV, if given) and the position on the sky (to be accessible for summer observations from the Maidanak Observatory, Uzbekistan). Nearly all of the 45 stars selected in this way are from objectiveprism surveys by Bond (1970) and Bidelman & MacConnell (1973) and were originally classified as slightly or moderately weak-lined stars. We had expected, on grounds of line-weakening alone, that part of the stars in this sample could be identified with the thick disk population.…”

Section: Selection Of Starsmentioning

confidence: 99%

Photoelectric Vilnius photometry of Hipparcos turn-off region stars

Bartasiute¹,

Ezhkova²,

Lazauskaite³

1999

Open Astronomy

View full text Add to dashboard Cite

Abstract. Seven-color photometry in the Vilnius system and photometric classification in terms of spectral type, absolute magnitude and metallicity are presented for 145 Hipparcos stars of the turn-off region, most of which have parallaxes determined to an accuracy of at least 15%. The stars selected for the observing program included those identified kinematically as intermediate between the thin disk and halo, plus a number of weak-lined stars discovered previously from objective prism surveys. The metallicity distribution we find for a kinematically defined sample of possible members of the thick disk has a mean abundance [Fe/H]=-0.3 dex and a dispersion of 0.3 dex. Our data seem to suggest a large age for this intermediate population.

show abstract

On the space distribution of Ap, Am stars

Kharadze

Bartaya

1977

Astron Nachr

View full text Add to dashboard Cite

Some questions concerning the space distribution of Ap and Am stars have been discussed on the basis of the Abastumani Catalogue containing the data in the two-dimensional MK classification for stars in Kapteyn Areas Nos 2-43, Ap and Am stars do not show the high concentration towards the galactic plane as normal stars of the same spectral interval. Moreover, Ap stars occur at distances up to about zoo pc from the galactic plane, Am stars up to about 400 pc.Auf der Grundlage des Abastumani-Iiatalogs, der Angaben iiber die zweidimensionale Spektralklassifikation im MI<-System ftir die Sterne der Kapteynschen Felder z bis 43 enthalt, werden Fragen betrachtet, die die raumliche Verteilung der Ap-und Am-Sterne betreffen. Die Ap-und Am-Sterne sind niclit so stark zur galaktischen Ebene konzentriert \vie normale Sterne gleichen Spektraltyps. Die Ap-Sterne haben Entfernungen von der galaktischen Ebene bis zu etwa zoo pc, die Am-Sterne bis zu etwa 400 pc.It is important to explore the physical, kinematic and other characteristics of Ap, Am-type stars because of many problems in astrophysics and stellar astronomy. In particular one has to know the cause of the anomalies observed in their spectra: do they indicate some stage in the evolutionary sequence of A stars or do they represent an independent group of stars of peculiar chemical composition and origin; and, finally, what is their age or the age of Ap stars with respect to Am stars?The knowledge of the number of these stars, their percentage in the total number of A-type stars and also the characteristics of space distribution may throw light upon the nature of the objects under consideration. But very poor data of that kind are available by now and they are hardly uniform ( JASCHEK and JASCHEK 1967).In Kapteyn (KA) Nos 2-43 (declination circles of 75", 60°, 45") the spectra of 10396 stars were classified in the MK system (BARTAYA and KHARADZE 1970;KHARADZE and BARTAYA 1973). This classification revealed 173 stars with some anomalies in their spectra. The bulk of them (154) belong t o Ap, Am stars.We regarded the analysis of the material to be of some interest, when we consider two points: I) this number with respect to the total number of all known Ap, Am stars is not insignificant with no reference to the recently published Catalogue of A stars of the Southern Sky (BIDELMAN and MACCONNELL 1973) ; 2) in our case we have quite uniform data for the 42 relatively regularly distributed directions from the galactic plane to as far as nearly to the galactic north pole and all A stars have been simultaneously classified right up to mpg = 1om8. Figure I shows the percentage distribution according to the spectral classes of 154 Ap, Am stars revealed in Abastumani. Following our classification based on the estimate of the K/H ratio, Ap stars appear to occur in the spectral interval of B8-A3 being mainly concentrated in the interval of B8-Ao. The Am stars belong to Ao-A5 being concentrated in the interval of Az-Ag. This picture does not contradict the data of JASCHEK and JASCH...

show abstract

The brighter stars of astrophysical interest in the southern sky.

Cited by 160 publications

References 0 publications

Chromospherically Active Stars. XXIV. The Giant, Single-lined Binaries HD 37824, HD 181809, and HD 217188

Chromospherically Active Stars. XXIV. The Giant, Single-lined Binaries HD 37824, HD 181809, and HD 217188

Photoelectric Vilnius photometry of Hipparcos turn-off region stars

On the space distribution of Ap, Am stars

Contact Info

Product

Resources

About