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  <controlfield tag="001">2268</controlfield>
  <controlfield tag="005">20160701171702.0</controlfield>
  <datafield tag="037" ind1=" " ind2=" ">
    <subfield code="a">ASTROimport-425</subfield>
  </datafield>
  <datafield tag="100" ind1=" " ind2=" ">
    <subfield code="a">Martayan, C.</subfield>
  </datafield>
  <datafield tag="260" ind1=" " ind2=" ">
    <subfield code="c">2011</subfield>
  </datafield>
  <datafield tag="245" ind1=" " ind2=" ">
    <subfield code="a">Evolution of massive Be and Oe stars at low metallicity towards the Long Gamma Ray bursts</subfield>
  </datafield>
  <datafield tag="520" ind1=" " ind2=" ">
    <subfield code="a">stars rotate faster than in environments of high metallicity. This is a typical case in the SMC. As a consequence, it is expected that a larger number of fast rotators is found in the SMC than in the Galaxy, in particular a higher fraction of Be/Oe stars. Using the ESO-WFI in its slitless mode, the data from the SMC open clusters were examined and an occurrence of Be stars 3 to 5 times larger than in the Galaxy was found. The evolution of the angular rotational velocity at different metallicities seems to be the main key to understand the specific behavior and evolution of these stars. According to the results form the WFI study, the observational clues drawn from the WR stars and other massive stars in the SMC, and relying on the model predictions regarding the characteristics that LGRBs-progenitors should have on the ZAMS, we concluded that low metallicity Oe/Be stars are potential progenitors of LGRBs. In this document, we describe the different steps followed in these studies: determination of the number of Be/Oe stars at different metallicities, identification of the clues that lead to suppose the low metallicity Be/Oe stars as LGRB progenitors, comparison of models with observations. </subfield>
  </datafield>
  <datafield tag="700" ind1=" " ind2=" ">
    <subfield code="a"> Zorec, J.</subfield>
  </datafield>
  <datafield tag="700" ind1=" " ind2=" ">
    <subfield code="a"> Baade, D.</subfield>
  </datafield>
  <datafield tag="700" ind1=" " ind2=" ">
    <subfield code="a"> Frémat, Y.</subfield>
  </datafield>
  <datafield tag="700" ind1=" " ind2=" ">
    <subfield code="a"> Fabregat, J.</subfield>
  </datafield>
  <datafield tag="700" ind1=" " ind2=" ">
    <subfield code="a"> Ekström, S.</subfield>
  </datafield>
  <datafield tag="773" ind1=" " ind2=" ">
    <subfield code="p">Bulletin de la Societe Royale des Sciences de Liege</subfield>
    <subfield code="v">80</subfield>
    <subfield code="y">2011</subfield>
    <subfield code="c">285-290</subfield>
  </datafield>
  <datafield tag="856" ind1="4" ind2="2">
    <subfield code="a">http://esoads.eso.org/abs/2011BSRSL..80..285M</subfield>
  </datafield>
  <datafield tag="905" ind1=" " ind2=" ">
    <subfield code="a">published in</subfield>
  </datafield>
  <datafield tag="980" ind1=" " ind2=" ">
    <subfield code="a">REFERD</subfield>
  </datafield>
</record>
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