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Several studies have shown recently that at low metallicity B-type starsrotate faster than in environments of high metallicity. This is a typical casein the SMC. As a consequence, it is expected that a larger number of fastrotators is found in the SMC than in the Galaxy, in particular a higherfraction of Be/Oe stars. Using the ESO-WFI in its slitless mode, the data fromthe SMC open clusters were examined and an occurrence of Be stars 3 to 5 timeslarger than in the Galaxy was found. The evolution of the angular rotationalvelocity at different metallicities seems to be the main key to understand thespecific behavior and evolution of these stars. According to the results fromthis WFI study, the observational clues obtained from the SMC WR stars andmassive stars, and the theoretical predictions of the characteristics must havethe long gamma-ray burst progenitors, we have identified the low metallicitymassive Be and Oe stars as potential LGRB progenitors. To this end, the ZAMSrotational velocities of the SMC Be/Oe stars were determined and compared tomodels. The expected rates and the numbers of LGRB were then calculated andcompared to the observed ones. Thus, a high probability was found that lowmetallicity Be/Oe stars can be LGRB progenitors. In this document, we describethe different steps followed in these studies: determination of the number ofBe/Oe stars at different metallicities, identification of the clues that leadto suppose the low metallicity Be/Oe stars as LGRB progenitors, comparison ofmodels with observations.

Evolution of massive Be and Oe stars at low metallicity towards the Long  Gamma Ray bursts\footnote{Based on ESO runs 069.D-0275(A), 072.D-0245(A) and  (C).}