Results 1 to 10 of about 91,631 (165)
Rotation, planets, and the 'second parameter' of the horizontal branch [PDF]
Monthly Notices of the Royal Astronomical Society, 2000 We analyze the angular momentum evolution from the red giant branch (RGB) to the horizontal branch (HB) and along the HB. Using rotation velocities for stars in the globular cluster M13, we find that the required angular momentum for the fast rotators is up to 1-3 orders of magnitude (depending on some assumptions) larger than that of the sun.
Noam Soker, Noam Soker ⋆, Soker Noam
exaly +3 more sources
Red horizontal branch stars: An asteroseismic perspective
Astronomy and Astrophysics, 2023 Robust age estimates of red giant stars are now possible thanks to the precise inference of their mass based on asteroseismic constraints. However, there are cases where such age estimates can be highly precise yet very inaccurate. An example is giants that have undergone mass loss or mass transfer events that have significantly altered their mass.
M Matteuzzi +2 more
exaly +4 more sources
Meikuang Anquan, 2021 This paper takes the multi-branch horizontal grouting well reinforced with limestone on the corresponding floor L8 in the 15011 coal seam working face of Zhaogu No.1 Mine as the research object.
LIU Xiugang +3 more
doaj +1 more source
Identification of Blue Horizontal-branch Stars from LAMOST DR5
The Astrophysical Journal Supplement Series, 2023 We construct a new catalog of the blue horizontal-branch (BHB) stars from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR5 data set, which contains 5355 + 81 BHB stars at high Galactic latitude (∣Glat∣ > 20°).
Jie Ju +8 more
doaj +1 more source
Symposium - International Astronomical Union, 1974 The properties of horizontal branch stars depend on the amount of carbon, nitrogen and oxygen that they contain but all theoretical models have difficulty in explaining those stars right at the blue end of the horizontal branch. The length of the theoretical evolutionary tracks always appears to be less than what is observed.
R. J. Tayler, J. E. Hesser
openaire +2 more sources
Geofluids, 2022 Multibranched horizontal well is an important means to develop low permeability reservoirs. Fishbone multibranched horizontal well has the advantages of increasing drainage area, reducing drilling number, utilizing existing wells, and saving oilfield ...
Shukai Tang +4 more
doaj +1 more source
The horizontal-branch A stars [PDF]
Publications of the Astronomical Society of the Pacific, 1979 The observational determination of astrophysical parameters of horizontal-branch A stars is discussed. Effective temperatures, surface gravities, and bolometric magnitudes are determined for seven field horizontal-branch A stars, and their masses are calculated. The mean mass for these seven stars is 0.6 + or - 0.4 solar mass.
D. S. Hayes, A. G. D. Philip
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Horizontal Branch Evolution [PDF]
International Astronomical Union Colloquium, 1989 AbstractIn 1973 the outstanding problems confronting the theory of horizontal branch evolution were the “second parameter” problem and the Oosterhoff Effect. Despite significant progress, particularly in the observations and in the observation/theory interface, they remain as the outstanding problems of 1988.
R.T. Rood, D.A. Crocker
openaire +1 more source
The Astronomical Journal, 2023 Wide-field and deep DECam multiband photometry, combined with HST data for the core of the Galactic globular cluster NGC 2808, allowed us to study the distribution of various stellar subpopulations and stars in different evolutionary phases out to the ...
Christian I. Johnson +9 more
doaj +1 more source
Numerical Simulation Study Of Squeezed Branch Piles Based On Post-grouting Technology [PDF]
E3S Web of Conferences, 2021 The squeezed branch pile has strong resistance to pressure, pullout and horizontal force, and it also has excellent stability, which makes it widely used in the field of electrical engineering.
Ma LiXing +4 more
doaj +1 more source