A merger between two stars may sound like an exotic event, but for massive stars this is not rare at all. About a quarter has a companion that is so close that the two stars will coalesce to form a new rejuvenated star (Sana, de Mink et al. Science 2012). In this paper we simulate the evolution of the stars and their interaction processes. We predict the incidence of stellar mergers and other products of binary evolution among a typical stellar population. Furthermore we show that these products typically appear to be single stars. Published in Astrophysical Journal, De Mink et al. (2014).
Seventy percent of all O-stars is expected to interact with a binary companion during it’s life. The mass changes resulting from such interactions and stellar winds leave characteristic signatures in stellar mass function of young star clusters. Using these we model the mass functions of the Arches and Quintuplet cluster accounting for binary interaction and derive an age of 3.5+/-0.7 Myr and 4.8+/-0.1 Myr. Based on our simulations, we expect the most massive 9+/-3 stars in Arches and 8+/-3 in Quintuplet to be the product of binary evolution. We propose this as a solution to the long standing age controversy for these clusters and we discuss the implications for the upper stellar mass limit
ApJ in press, SCHNEIDER, IZZARD, DE MINK , LANGER, STOLTE, DE KOTER, GVARAMADZE, HUSSMANN, LIERMANN & SANA
Today the first data of my very first own Hubble proposal is coming in. I feel excited as a child. Especially since I am from the generation that grew up as children with pictures from Hubble. And now, finally the first data is coming in. Still unprocessed and it is not yet clear how good the data is, but it looks so pretty already.
The most massive stars end are believed to end their lives as Wolf-Rayet stars, very hot and luminous. In this study the spectrum of an extremely hot and bright ionizing Wolf-Rayet star, DR1, is analyzed. The star is embedded in … Read More »
Globular clusters are old compact systems containing up to a about a million of stars. How so many stars form in such a small area still remains unclear. A particular puzzling feature is that effectively all globular cluster appear to harbor more than one stellar population within them.
In this paper we propose that a first generation of massive stars polluted their lower mass sisters while they were still fully convective PMS stars. While details still need to be worked out, a very attractive feature of this scenario is that it provides a solution for the long standing mass budget problem.
“Early Disc Accretion as the Origin of Abundance Anomalies in Globular Clusters“, by Bastian, Lamers, de Mink, Longmore, Goodwin & Gieles, 2013, MNRAS in press.
LEGUS, the Legacy ExtraGalactic UV Survey, has been granted 154 orbits of time on the Hubble Space Telescope to obtain NUV,U,B,V,I imaging for 50 nearby galaxies (closer than about 11 Mpc) that have been carefully selected to span the full … Read More »
Stellar models suggest that rotation can have drastic impact on the evolution of massive stars, but various aspects of these effects remain highly uncertain. One of the best place to study these effects is in #0 Doradus, which contains a … Read More »
The Hubble Tarantula Treasury Project (HTTP), an ongoing multi color imaging survey lead by Elena Sabbi of stellar populations in the Tarantula Nebula in the Large Magellanic Cloud that reaches into the sub-solar mass regime. An observational overview and first … Read More »
What fraction of the slow dusty wind of an AGB star can be captured by a binary companion? According to smooth particle hydro simulations by Mohammed, quite a bit more than is typically accounted for in binary evolutionary models. Especially … Read More »
Why do stars rotate the way they do? Nature or Nurture? Is their rotation rate set by their birth conditions or is it the result from evolutionary effects? For single stars their rotation rate remain almost unchanged as they evolve … Read More »