Related papers: Two massive stars possibly ejected from NGC 3603 v…

We present new large field observations of molecular clouds with NANTEN2 toward the super star cluster NGC3603 in the transitions 12CO(J=2-1, J=1-0) and 13CO(J=2-1, J=1-0). We suggest that two molecular clouds at 13 km s-1 and 28 km s-1 are…

We measure transverse proper motion velocities of LMC Wolf-Rayet (WR) stars using Gaia DR3 astrometry. The combined velocity distribution of WNh, O If*/WN, and WNL very massive stars ($>100\ M_\odot$; VMS) shows both slow, unejected objects…

WR~21a was known as a massive spectroscopic binary composed of an O2.5 If*/WN6ha primary and an O3 V((f*))z secondary. Although a minimum value, the mass estimated for the primary placed it as one of the most massive stars found in our…

The external destruction of protoplanetary discs in a clustered environment acts mainly due to two mechanisms: gravitational drag by stellar encounters and evaporation by strong stellar winds and radiation. If encounters play a role in disc…

We present the first results from our survey of the star-forming complex W3, combining VRI photometry with multiobject spectroscopy to identify and characterize the high-mass stellar population across the region. With 79 new spectral…

We have collected archival data on NGC7673 to constrain the star-formation history that produced the young star clusters and the field stellar population in this galaxy during the last 2 Gyr. We have considered the sample of 50 star…

The structure and kinematics of ionized gas in the star-forming region in the BCD galaxy VIIZw403 (UGC6456) are analyzed using observations with the SCORPIO focal reducer on the 6-m Special Astrophysical Observatory telescope in three…

A new point of view on the dynamics of the circumstellar nebula M1-67 around the run-away Wolf-Rayet (WR) star WR 124 is presented. We found that it has been interacting with the surrounding ISM and has formed a bow shock due to its high…

We perform the largest currently available set of direct N-body calculations of young star cluster models to study the dynamical influence, especially through the ejections of the most massive star in the cluster, on the current relation…

I present a set of long-term, direct, relativistic many-body computations of model dense stellar clusters with up-to-date stellar-evolutionary, supernova (SN), and remnant natal-kick models, including pair instability and pulsation pair…

We explore the possibility that the G2 gas cloud falling in towards \sgra is the mass loss envelope of a young TTauri star. As the star plunges to smaller radius at 1000 to 6000 \kms, a strong bow shock forms where the stellar wind is…

Aims. Various studies indicate that interacting binary stars of Algol type evolve non-conservatively. However, direct detections of systemic mass loss in Algols have been scarce so far. We study the systemic mass loss in Algols by looking…

To date, the proposed observation of Young Stellar Objects (YSOs) in the Galactic center (GC) still raises the question where and how these objects could have formed due to the violent vicinity of Sgr~A*. Here, we report the…

The origin of rapid rotation in massive stars remains debated, although binary interactions are now often advocated as a cause. However, the broad and shallow lines in the spectra of fast rotators make direct detection of binarity…

The production of runaway massive binaries offers key insights into the evolution of close binary stars and open clusters. The stars HD 14633 and HD 15137 are rare examples of such runaway systems, and in this work we investigate the…

Hierarchical massive quadruple systems are ideal laboratories for examining the theories of star formation, dynamical evolution, and stellar evolution. The successive mergers of hierarchical quadruple systems might explain the mass gap…

The last decade has seen the detection of fast moving stars in the Galactic halo, the so-called hypervelocity stars (HVSs). While the bulk of this population is likely the result of a close encounter between a stellar binary and the…

We investigate the massive star content of NGC 3603, the closest known giant H II region. We have obtained spectra of 26 stars in the central cluster using the Baade 6.5-m telescope (Magellan I). Of these 26 stars, 16 had no previous…

Winds from massive stars have recently been deemed promising sites for investigating relativistic particle acceleration. Particularly, the resulting bow shock from the interaction of the winds of runaway stars with interstellar matter has…

Young massive stars and stellar clusters continuously form in the Galactic disk, generating new HII regions within their natal giant molecular clouds and subsequently enriching the interstellar medium via their winds and supernovae. Massive…