The VLT-FLAMES survey of massive stars: Observations   in the Galactic 
clusters NGC 3293, NGC 4755 and NGC 6611

Evans, Christopher J.; Smartt, S. J.; Lee, J.K.; Lennon, D. J.; Kaufer, A.; Dufton, P. L.; Trundle, C.; Herrero, A.; Simón‐Díaz, S.; Koter, A. de; Hamann, W. R.; Hendry, .; Hunter, I.; Irwin, M. J.; Korn, A. J.; Kudritzki, Rolf‐Peter; Langer, N.; Mokiem, M.R.; Najarro, F.; Pauldrach, A. W. A.; Przybilla, N.; Puls, J.; Ryans, R.; Urbaneja,; Venn, Kim A.; Villamariz, M. R.

doi:10.1051/0004-6361:20042446

Cited by 164 publications

(171 citation statements)

References 84 publications

(165 reference statements)

Supporting

Mentioning

163

Contrasting

Order By: Relevance

“…The spectral types derived from the BCD method agree very well with the determinations by Evans et al (2005) using the MK system, with the Hγ equivalent widths and the Balona & Crampton (1974) calibration, for 14 stars in common. The exception is CPD−59 4530, for which we determine a spectral type of B6 V in accordance with Feast (1963) …”

Section: Ngc 4755supporting

confidence: 73%

“…4.2.2, as well as the distance, which in this case is d = 2460 pc. The spectral types derived from the BCD method and those obtained by Evans et al (2005) using the MK system agree excellently. However, T eff values obtained with the BCD method show in general a good agreement with the values derived by Dufton et al (2006), although some discrepancies of about of 2000 K are observed in subtypes B1 and B2; i.e.…”

Section: Ngc 4755mentioning

confidence: 63%

“…(4) Spectral types taken from Schild (1970). (5) Spectral types taken from Evans et al (2005) and Dufton et al (2006).…”

Section: Fundamental Parameters Of the Starsmentioning

confidence: 99%

See 2 more Smart Citations

Open clusters

Aidelman

Cidale

Zorec

et al. 2012

A&A

View full text Add to dashboard Cite

Context. Spectroscopic investigations of galactic open clusters are scarce and limited to a reduced sample of cluster members. Aims. We intend to perform a complete study of the physical parameters of two galactic clusters as well as of their individual members. Methods. To carry out this study, we used the BCD (Barbier-Chalonge-Divan) spectrophotometric system, which is based on the study of the Balmer discontinuity and is independent of interstellar and circumstellar extinction. Additional physical properties were derived from the line profiles (FWHM) and stellar evolution models. We analyzed low-resolution spectra around the Balmer discontinuity for normal B-type and Be stars in two open clusters: NGC 3766 and NGC 4755. We determined the stellar fundamental parameters, such as effective temperatures, surface gravities, spectral types, luminosity classes, absolute and bolometric magnitudes, and color gradient excesses. The stellar rotation velocity was also determined. Complementary information, mainly stellar mass, age, and radius of the star population were calculated using stellar evolution models. In some cases, the stellar fundamental parameters were derived for the first time. The obtained results allowed us also to determine the reddening, age, and distance to the clusters. Results. The cluster parameters obtained through the BCD method agree very well with those derived from classical methods based on photometric data. The BCD system also provides physical properties of the star members. This study enables us to test the good behavior of M bol (λ 1 , D)-calibrations and detect systematic discrepancies between log g estimates from model atmospheres and those derived from stellar evolution models. To improve our knowledge on the formation and evolution of the clusters, more statistical studies on the initial mass luminosity and angular momentum distributions should be addressed. Therefore, the BCD spectrophotometric system could be a powerful tool for studying far galactic and extragalactic clusters with the generation of large telescopes and the multi-object technique.

show abstract

Section: Ngc 4755supporting

confidence: 73%

Section: Ngc 4755mentioning

confidence: 63%

See 1 more Smart Citation

Open clusters

Aidelman

Cidale

Zorec

et al. 2012

A&A

View full text Add to dashboard Cite

show abstract

“…A critical examination by Maeder et al (2014) of the nitrogen abundances estimated in the FLAMES survey (Evans et al 2005;Hunter et al 2008a) advocated the use of N/C against N/O abundance ratio diagrams. In theory, this could provide a powerful diagnostic.…”

Section: Element Abundancesmentioning

confidence: 99%

“…The VLT-FLAMES Survey of massive stars (Evans et al 2005(Evans et al , 2006 provided high-quality observations of an unprecedented number of B-type stars in the Galaxy and the Large and Small Magellanic Clouds (LMC and SMC, respectively). Quantitative analysis of these objects was presented in a series of articles by Dufton et al (2006), Trundle et al (2007), Hunter et al (2007Hunter et al ( , 2008aHunter et al ( ,b, 2009a, and Dunstall et al (2011).…”

Section: Introductionmentioning

confidence: 99%

The VLT-FLAMES Tarantula Survey

McEvoy

Dufton

Evans

et al. 2015

A&A

Self Cite

View full text Add to dashboard Cite

Context. Model atmosphere analyses have been previously undertaken for both Galactic and extragalactic B-type supergiants. By contrast, little attention has been given to a comparison of the properties of single supergiants and those that are members of multiple systems. Aims. Atmospheric parameters and nitrogen abundances have been estimated for all the B-type supergiants identified in the VLT-FLAMES Tarantula survey. These include both single targets and binary candidates. The results have been analysed to investigate the role of binarity in the evolutionary history of supergiants.Methods.  non-local thermodynamic equilibrium (LTE) model atmosphere calculations have been used to determine atmospheric parameters and nitrogen abundances for 34 single and 18 binary supergiants. Effective temperatures were deduced using the silicon balance technique, complemented by the helium ionisation in the hotter spectra. Surface gravities were estimated using Balmer line profiles and microturbulent velocities deduced using the silicon spectrum. Nitrogen abundances or upper limits were estimated from the N  spectrum. The effects of a flux contribution from an unseen secondary were considered for the binary sample. Results. We present the first systematic study of the incidence of binarity for a sample of B-type supergiants across the theoretical terminal age main sequence (TAMS). To account for the distribution of effective temperatures of the B-type supergiants it may be necessary to extend the TAMS to lower temperatures. This is also consistent with the derived distribution of mass discrepancies, projected rotational velocities and nitrogen abundances, provided that stars cooler than this temperature are post-red supergiant objects. For all the supergiants in the Tarantula and in a previous FLAMES survey, the majority have small projected rotational velocities. The distribution peaks at about 50 km s −1 with 65% in the range 30 km s −1 ≤ v e sin i ≤ 60 km s −1 . About ten per cent have larger v e sin i (≥100 km s −1 ), but surprisingly these show little or no nitrogen enhancement. All the cooler supergiants have low projected rotational velocities of ≤70 km s −1 and high nitrogen abundance estimates, implying that either bi-stability braking or evolution on a blue loop may be important. Additionally, there is a lack of cooler binaries, possibly reflecting the small sample sizes. Single-star evolutionary models, which include rotation, can account for all of the nitrogen enhancement in both the single and binary samples. The detailed distribution of nitrogen abundances in the single and binary samples may be different, possibly reflecting differences in their evolutionary history. Conclusions. The first comparative study of single and binary B-type supergiants has revealed that the main sequence may be significantly wider than previously assumed, extending to T eff = 20 000 K. Some marginal differences in single and binary atmospheric parameters and abundances have been identified, possibly implying non-stand...

show abstract

Massive Stars as Tracers for Stellar and Galactochemical Evolution

Przybilla¹

2008

Reviews in Modern Astronomy

View full text Add to dashboard Cite

The VLT-FLAMES survey of massive stars: Observations in the Galactic clusters NGC 3293, NGC 4755 and NGC 6611

Cited by 164 publications

References 84 publications

Open clusters

Open clusters

The VLT-FLAMES Tarantula Survey

Massive Stars as Tracers for Stellar and Galactochemical Evolution

Contact Info

Product

Resources

About