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Half or more of stars more massive than our Sun are orbited by a companion star in a binary system. Many binaries have short enough orbits that the evolution of both stars is greatly altered by an exchange of mass and angular momentum between the stars. Such mass transfer is highly likely on the asymptotic giant branch (AGB) because this is when a star is both very large and has strong wind mass loss. Direct mass transfer truncates the AGB, and its associated nucleosynthesis, prematurely compared to in a single star. In wide binaries we can probe nucleosynthesis in the long-dead AGB primary star by today observing its initially lower-mass companion. The star we see now may be polluted by ejecta from the primary either through a wind or Roche-lobe overflow. We highlight recent quantitative work on nucleosynthesis in (ex-)AGB mass-transfer systems, such as carbon and barium stars, the link between binary stars and planetary nebulae, and suggest AGB stars as a possible source of the enigmatic element, lithium.
Bright Be star beta CMi has been identified as a non-radial pulsator on the basis of space photometry with the MOST satellite and also as a single-line spectroscopic binary with a period of 170.4 d. The purpose of this study is to re-examine both the
Sommerfeld called the first part of the second law to be the entropy axiom, which is about the existence of the state function entropy. It was usually thought that the second part of the second law, which is about the non-decreasing nature of entropy
We investigate the properties of a sample of 35 galaxies, detected with ALMA at 1.1 mm in the GOODS-ALMA field (area of 69 arcmin$^2$, resolution = 0.60, RMS $simeq$ 0.18 mJy beam$^{-1}$). Using the UV-to-radio deep multiwavelength coverage of the GO
We use the AllWISE Data Release to continue our search for WISE-detected motions. In this paper, we publish another 27,846 motion objects, bringing the total number to 48,000 when objects found during our original AllWISE motion survey are included.
In an $SU(2)_R$ extension of the standard model, it is shown how the neutral fermion $N$ in the doublet $(N,e)_R$ may be assigned baryon number $B=1$, in contrast to its $SU(2)_L$ counterpart $ u$ in the doublet $( u,e)_L$ which has lepton number $L=