Volume 504, Number 1, September II 2009
Page(s) 211 - 211
Section Stellar structure and evolution
Published online 11 August 2009


The VLT-FLAMES survey of massive stars: atmospheric parameters and rotational velocity distributions for B-type stars in the Magellanic Clouds

I. Hunter1 - D. J. Lennon2 - P. L. Dufton1 - C. Trundle1 - S. Simón-Díaz3 - S. J. Smartt1 - R. S. I. Ryans1 - C. J. Evans4

1 - Astrophysics Research Centre, School of Mathematics & Physics, The Queen's University of Belfast, Belfast, BT7 1NN, Northern Ireland, UK
2 - Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
3 - LUTH, Observatoire de Meudon, 5 Place Jules Janssen, 92195 Meudon Cedex, France
4 - UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ, UK

A&A 457, 265-280 (2006), DOI: 10.1051/0004-6361:20065392
A&A 479, 541-555 (2008), DOI: 10.1051/0004-6361:20078511

We correct the estimates of the dispersions in the rotational velocities for early-type stars in our Galaxy (Dufton et al. 2006, A&A, 457, 265) and the Magellanic Clouds (Hunter et al. 2008, A&A, 479, 541). The corrected values are $\pi^{\frac{1}{4}}$ (i.e. approximately 33%) larger than those published in the original papers.

Key words: stars: early-type - stars: fundamental parameters - stars: rotation - stars: evolution - errata, addenda

In two recent papers, we have estimated projected rotational velocities for samples of early-type stars in our Galaxy (Dufton et al. 2006) and in the Small and Large Magellanic Clouds (Hunter et al. 2008). These observed values were used to deduce the underlying distribution of rotational velocities assuming that they followed a Gaussian distribution, viz.

\begin{displaymath}f(v){\rm d}v \propto \exp \left (- \left (\frac{v-v_0}{\Delta v} \right )^2 \right ) {\rm d}v

where $f(v){\rm d}v$ is the fraction of stars with a velocity of v and in a range of velocities, ${\rm d}v$.

The values quoted for the most likely velocity, v0, were correct but those for the velocity dispersions, $\Delta v$, should be increased by a factor of $\pi^{\frac{1}{4}}$ (i.e. by approximately 33%). The original values for v0 and the corrected values for $\Delta v$ are listed in Table 1. Also listed are the standard deviations, $\sigma$, for a normal distribution given by:

\begin{displaymath}f(v){\rm d}v \propto \exp \left (-\frac{1}{2} \left (\frac{v-v_0}{\sigma}\right )^2\right ) {\rm d}v.

Table 1:   Mean rotational velocities and corrected dispersions for the different FLAMES samples.

Note that $\Delta v$ and $\sigma$ are related by a factor of the square root of two. As in the original papers, all values have been rounded to the nearest 5 km s-1.

We thank Ines Brott for alerting us to this error and for advice on how to present the corrected results.


All Tables

Table 1:   Mean rotational velocities and corrected dispersions for the different FLAMES samples.

Copyright ESO 2009

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.