Results 71 to 80 of about 139 (112)

Binary Fraction in Galactic Star Clusters: FSR 866, NGC 1960, and STOCK 2

The Astronomical Journal
The study of binary stars in different astronomical environments offers insights into the dynamical state of the hosting stellar systems. The binary fraction in fact plays a crucial role in the dynamical evolution of stellar systems, regulating processes
L. Yalyalieva, A. Chemel, G. Carraro, E. Glushkova   +3 more
doaj   +1 more source

Kinematic fingerprints of dynamical ejection: High-velocity blue straggler stars in the halo of NGC 188

Astronomy & Astrophysics
Context. Open clusters are fundamental laboratories for studying stellar dynamics. In dynamically mature systems such as NGC 188 (~7 Gyr), mass segregation is expected to concentrate massive objects in the core, making the presence of high-mass stars in ...
Chi Huanbin
doaj   +1 more source

WIYN Open Cluster Study. XCVII. An Extended Radial-velocity Survey and Spectroscopic Binary Orbits in the Open Cluster NGC 188

The Astronomical Journal
We present 35 new spectroscopic-binary orbits from our extended radial-velocity (RV) survey of the old (6.4 ± 0.2 Gyr) open cluster NGC 188. Using data from the WIYN Open Cluster Study (WOCS) and APOGEE-2, this work nearly doubles the temporal baseline ...
Ritvik Sai Narayan, Evan Linck, Robert D. Mathieu, Aaron M. Geller   +3 more
doaj   +1 more source

Once a Triple, Not Always a Triple: The Evolution of Hierarchical Triples That Yield Merged Inner Binaries

The Astrophysical Journal
More than half of all main-sequence (MS) stars have one or more companions, and many of those with initial masses 10 yr) companions. Furthermore, both BSS binaries and DWDs exhibit signatures of WD birth kicks.
Cheyanne Shariat, Smadar Naoz, Kareem El-Badry, Antonio C. Rodriguez, Bradley M. S. Hansen, Isabel Angelo, Alexander P. Stephan   +6 more
doaj   +1 more source

Blue Straggler in the Making: An X-Ray Active Binary in Algol Configuration

The Astrophysical Journal Letters
We report an extremely rare X-ray active blue straggler star (BSS) in Collinder 261, undergoing ongoing Roche-lobe overflow in a semidetached binary in an Algol-type configuration with an orbital period of P _orb  ∼ 2.112 days, providing direct ...
A. H. Sheikh, Biman J. Medhi, Annapurni Subramaniam, Sergio Messina, Susmita Das, Hitendra Sarkar, Anupam Bhardwaj, Atila Poro, Marina Kounkel, Ram Sagar   +9 more
doaj   +1 more source

Stellar Spin-down in Post-mass-transfer Binary Systems

The Astrophysical Journal
Motivated by measurements of the rotation speed of accretor stars in post-mass-transfer (post-MT) systems, we investigate how magnetic braking affects the spin-down of individual stars during binary evolution with the MESAbinary module.
Meng Sun, Seth Gossage, Emily M. Leiner, Aaron M. Geller   +3 more
doaj   +1 more source

The Blue Straggler Star population in NGC6229 [PDF]

The Monthly Notices of the Royal Astronomical Society, 2012
N. Sanna, E. Dalessandro, B. Lanzoni, F. R. Ferraro, G. Beccari, R. T. Rood   +5 more
openaire   +2 more sources

The Impact of Stellar Rotations and Binaries on the Shape of Upper Main Sequence near Turnoff in Open Cluster NGC 6067

The Astrophysical Journal
We present the analysis of the extended main-sequence turnoff (eMSTO) in the open cluster NGC 6067. We derive the projected rotational velocity, v sin i , of the stars belonging to the eMSTO region of the main sequence (MS) utilizing Gaia-ESO spectra ...
Jayanand Maurya, Yu Zhang, Sebastian Kamann, Hubiao Niu, Yves Frémat, Kaixiang Lang, Y. C. Joshi, M. R. Samal, Peter De Cat, Ali Esamdin   +9 more
doaj   +1 more source

The Distribution of Blue Straggler Stars in the Color–Magnitude Diagrams of Old Open Clusters

The Astronomical Journal
We examine the blue straggler star (BSS) populations of six old (≥4 Gyr) open clusters: M67, NGC 188, NGC 6791, Berkeley 32, Berkeley 39, and Trumpler 19.
Evan Linck, Robert D. Mathieu
doaj   +1 more source

Discovery of a Barium Blue Straggler Star in M67 and “Sighting” of Its White Dwarf Companion

The Astrophysical Journal Letters
We report the discovery of a barium blue straggler star (BSS) in M67, exhibiting enhancements in slow neutron-capture ( s -)process elements. Spectroscopic analysis of two BSSs (WOCS 9005 & WOCS 1020) and four stars located near the main-sequence turn ...
Harshit Pal, Annapurni Subramaniam, Arumalla B. S. Reddy, Vikrant V. Jadhav   +3 more
doaj   +1 more source