Spinning like a blue straggler: The population of fast rotating blue straggler stars in ω centauri

A. Mucciarelli, L. Lovisi, F. R. Ferraro, E. Dalessandro, B. Lanzoni, L. Monaco

Resultado de la investigación: Article

8 Citas (Scopus)

Resumen

By using high-resolution spectra acquired with FLAMES-GIRAFFE at the ESO/VLT, we measured the radial and rotational velocities for 110 blue straggler stars (BSSs) in ω Centauri, the globular cluster-like stellar system harboring the largest known BSS population. According to their radial velocities, 109 BSSs are members of the system. The rotational velocity distribution is very broad, with the bulk of BSSs spinning at less than 40 km s-1 (in agreement with the majority of such stars observed in other globular clusters) and a long tail reaching 200 km s-1. About 40% of the sample has ve sin i > 40 km s-1 and about 20% has ve sin i > 70 km s-1. Such a large fraction is very similar to the percentage of fast rotating BSSs observed in M4. Thus, ω Centauri is the second stellar cluster, beyond M4, with a surprisingly high population of fast spinning BSSs. We found a hint of radial behavior for a fraction of fast rotating BSSs, with a mild peak within one core radius, and a possible rise in the external regions (beyond four core radii). This may suggest that recent formation episodes of mass transfer BSSs occurred preferentially in the outskirts of ω Centauri, or that braking mechanisms able to slow down these stars are least efficient in the lowest density environments.

Idioma originalEnglish
Número de artículo43
PublicaciónAstrophysical Journal
Volumen797
N.º1
DOI
EstadoPublished - 10 dic 2014

Huella dactilar

blue stars
metal spinning
mass transfer
globular clusters
radial velocity
stars
stellar systems
radii
braking
European Southern Observatory
velocity distribution
high resolution

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Citar esto

Mucciarelli, A. ; Lovisi, L. ; Ferraro, F. R. ; Dalessandro, E. ; Lanzoni, B. ; Monaco, L. / Spinning like a blue straggler : The population of fast rotating blue straggler stars in ω centauri. En: Astrophysical Journal. 2014 ; Vol. 797, N.º 1.
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abstract = "By using high-resolution spectra acquired with FLAMES-GIRAFFE at the ESO/VLT, we measured the radial and rotational velocities for 110 blue straggler stars (BSSs) in ω Centauri, the globular cluster-like stellar system harboring the largest known BSS population. According to their radial velocities, 109 BSSs are members of the system. The rotational velocity distribution is very broad, with the bulk of BSSs spinning at less than 40 km s-1 (in agreement with the majority of such stars observed in other globular clusters) and a long tail reaching 200 km s-1. About 40{\%} of the sample has ve sin i > 40 km s-1 and about 20{\%} has ve sin i > 70 km s-1. Such a large fraction is very similar to the percentage of fast rotating BSSs observed in M4. Thus, ω Centauri is the second stellar cluster, beyond M4, with a surprisingly high population of fast spinning BSSs. We found a hint of radial behavior for a fraction of fast rotating BSSs, with a mild peak within one core radius, and a possible rise in the external regions (beyond four core radii). This may suggest that recent formation episodes of mass transfer BSSs occurred preferentially in the outskirts of ω Centauri, or that braking mechanisms able to slow down these stars are least efficient in the lowest density environments.",
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Spinning like a blue straggler : The population of fast rotating blue straggler stars in ω centauri. / Mucciarelli, A.; Lovisi, L.; Ferraro, F. R.; Dalessandro, E.; Lanzoni, B.; Monaco, L.

En: Astrophysical Journal, Vol. 797, N.º 1, 43, 10.12.2014.

Resultado de la investigación: Article

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T1 - Spinning like a blue straggler

T2 - The population of fast rotating blue straggler stars in ω centauri

AU - Mucciarelli, A.

AU - Lovisi, L.

AU - Ferraro, F. R.

AU - Dalessandro, E.

AU - Lanzoni, B.

AU - Monaco, L.

PY - 2014/12/10

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KW - blue stragglers

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