A significant fraction of high redshift starburst galaxies presents strong Ly
alpha emission. Understanding the nature of these galaxies is important to
assess the role they played in the early Universe and to shed light on the
relation between the narrow band selected Lyalpha emitters and the Lyman break
galaxies: are the Lyalpha emitters a subset of the general LBG population? or
do they represent the youngest galaxies in their early phases of formation? We
studied a sample of UV continuum selected galaxies from z~2.5 to z~6 (U, B, V
and i-dropouts) from the GOODS-South survey, that have been observed
spectroscopically. Using the GOODS-MUSIC catalog we investigated their physical
properties, such as total masses, ages, SFRs, extinction etc as determined from
a spectrophotometric fit to the multi-wavelength (U band to mid-IR) SEDs, and
their dependence on the emission line characteristics. In particular we
determined the nature of the LBGs with Lyalpha in emission and compared them to
the properties of narrow band selected Lyalpha emitters. For U and B-dropouts
we also compared the properties of LBGs with and without the Lyalpha emission
line.Comment: 7 pages, proceedings of the conference "Probing Stellar Populations
out to the Distant Universe", Cefalu (Italy), September 7 - 19, 2008. To be
published in the AIP Conf. Proc. Serie