Expanding chromospheres of late G and K supergiants
نویسندگان
چکیده
منابع مشابه
Radio Detection of Late { Type ( G { K )
We report deep 3.6 cm radio observations of a small sample of the most rapidly{ rotating G{K dwarf stars in the Pleiades open cluster. Of the 4 ultra{fast rotators (UFRs) observed, 3 were detected. The G8 dwarf HII 1136, the fastest rotating G dwarf known in the Pleiades cluster, displayed a are that rose to a peak ux density of 1 mJy (peak radio luminosity of 210 16 erg Hz ?1 s ?1) in less tha...
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We report the detection of N V 1239Å transition region emission in HST/GHRS spectra of the A7 V stars, α Aql and α Cep. Our observations provide the first direct evidence of 1− 3 × 10 K material in the atmospheres of normal A-type stars. For both stars, and for the mid-A–type star τ 3 Eri, we also report the detection of chromospheric emission in the Si III 1206Å line. At a B−V color of 0.16 an...
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We investigate the effects of radiation pressure on the atmospheres of A, F and G-supergiants by calculating hydrodynamical model atmospheres for stars with 5500 ≤ Teff ≤ 9500 K. In the subsonic part of the wind, the radiation pressure by continuum and lines from Kurucz (1992) is taken into account. In the supersonic part of the wind, the radiation pressure is expressed in terms of the force mu...
متن کاملKnots with g(E(K)) = 2 and g(E(K#K#K)) = 6 and Morimoto’s Conjecture
We show that there exist knots K ⊂ S with g(E(K)) = 2 and g(E(K#K#K)) = 6. Together with [5, Theorem 1.5], this proves existence of counterexamples to Morimoto’s Conjecture [10]. This is a special case of [6]. Let Ki (i = 1, 2) be knots in the 3-sphere S, and let K1#K2 be their connected sum. We use the notation t(·), E(·), and g(·) to denote tunnel number, exterior, and Heegaard genus respecti...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1986
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/222.2.307