The Gaia-ESO Survey: membership and initial mass function of the γ Velorum cluster

DOI: 
10.1051/0004-6361/201527875
Publication date: 
01/05/2016
Main author: 
Prisinzano, L.
IAA authors: 
Alfaro, E. J.;Costado, M. T.
Authors: 
Prisinzano, L.;Damiani, F.;Micela, G.;Jeffries, R. D.;Franciosini, E.;Sacco, G. G.;Frasca, A.;Klutsch, A.;Lanzafame, A.;Alfaro, E. J.;Biazzo, K.;Bonito, R.;Bragaglia, A.;Caramazza, M.;Vallenari, A.;Carraro, G.;Costado, M. T.;Flaccomio, E.;Jofré, P.;Lardo, C.;Monaco, L.;Morbidelli, L.;Mowlavi, N.;Pancino, E.;Randich, S.;Zaggia, S.
Journal: 
Astronomy and Astrophysics
Publication type: 
Article
Volume: 
589
Pages: 
A70
Abstract: 
Context. Understanding the properties of young open clusters, such as the initial mass function (IMF), star formation history, and dynamic evolution, is crucial for obtaining reliable theoretical predictions of the mechanisms involved in the star formation process. <BR /> Aims: We want to obtain a list that is as complete as possible of confirmed members of the young open cluster γ Velorum, with the aim of deriving general cluster properties such as the IMF. <BR /> Methods: We used all available spectroscopic membership indicators within the Gaia-ESO public archive, together with literature photometry and X-ray data, and for each method, we derived the most complete list of candidate cluster members. Then, we considered photometry, gravity, and radial velocities as necessary conditions for selecting a subsample of candidates whose membership was confirmed by using the lithium and Hα lines and X-rays as youth indicators. <BR /> Results: We found 242 confirmed and 4 possible cluster members for which we derived masses using very recent stellar evolutionary models. The cluster IMF in the mass range investigated in this study shows a slope of α = 2.6 ± 0.5 for 0.5 〈M/M<SUB>☉</SUB>〈 1.3 and α = 1.1 ± 0.4 for 0.16 〈M/M<SUB>☉</SUB>〈 0.5, and it is consistent with a standard IMF. <BR /> Conclusions: The similarity of the IMF of the young population around γ<SUP>2</SUP>Vel to that in other star-forming regions and the field suggests it may have formed through very similar processes.Based on observations made with the ESO/VLT, at Paranal Observatory under program 188.B-3002 (The Gaia-ESO Public Spectroscopic Survey).Table 5 is only available at the CDS via anonymous ftp to <A href='http://cdsarc.u-strasbg.fr'>http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href='http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/589/A70'>http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/589/A70</A>
Database: 
ADS
SCOPUS
WOK
SCOPUS
URL: 
https://ui.adsabs.harvard.edu/#abs/2016A&A...589A..70P/abstract
ADS Bibcode: 
2016A&A...589A..70P
Keywords: 
stars: pre-main sequence;open clusters and associations: individual: γVelorum;stars: formation;stars: luminosity function;mass function;techniques: radial velocities;techniques: spectroscopic;Astrophysics - Solar and Stellar Astrophysics;Astrophysics - Astrophysics of Galaxies