A search for peculiar stars in the open cluster Hogg 16

PETR KURFURST; ERNST PAUNZEN; NAIRA M. AZATYAN; MARTIN NETOPIL; YAEL J. AIDELMAN; STEFANO CARIDDI; LYDIA STOFANOV; OLGA I. PINTADO

NEW ASTRONOMY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2018 p. 1 - 9

1384-1076

The study of chemically peculiar (CP) stars in open clusters provides valuable information about their evolutionary status.Their detection can be performed using the a photometric system, which maps their characteristic ux depression at 5200 A. This paper aims at studying the occurrence of CP stars in the earliest stages of evolution of a stellarpopulation by applying this technique to Hogg 16, a very young Galactic open cluster (age lower than 30 Myr). Weidentied several CP candidates: two B-type stars with a negative a index (CD􀀀60 4701, CPD􀀀60 4706) are likelyemission line (Be) stars, even though spectral measurements are necessary for a proper classication of the second one;a third object (CD􀀀60 4703), identied as a Be candidate in literature, appears to be a background B-type supergiantwith a none signicant a index, which does not rule out the possibility that it is indeed peculiar as the normality line ofa for supergiants has not been studied in detail yet. A fourth object (CD􀀀60 4699) appears to be a magnetic CP starof 8 M, but obtained spectral data seem to rule out this hypothesis. Two more magnetic CP star candidates are foundin the domain of early F-type stars, one close to the border of signicance and the other one appearing to be a pre-mainsequence object. This is very promising, as it can lead to very strong constraints to the diusion theory. Finally, wederived the fundamental parameters of Hogg 16 and provide for the rst time an estimate of its metal content.