The Formation of Massive Stars. I. High‐Resolution Millimeter and Radio Studies of High‐Mass Protostellar Candidates

AbstractUsing high resolution 3D hydrodynamical simulations we quantify the amount of mass accreted onto the secondary star of the binary system η Carinae during periastron passage on its highly eccentric orbit. The accreted mass is responsible for the spectroscopic event occurring every orbit close to periastron passage, during which many lines vary and the x-ray emission associated with the destruction wind collision structure declines. The system is mainly known for its giant eruptions that occurred in the nineteenth century. The high mass model of the system, M1=170M⊙ and M2=80M⊙, gives Macc≍ 3×10−6M⊙ compatible with the amount required for explaining the reduction in secondary ionization photons during the spectroscopic event, and also matches its observed duration. As accretion occurs now, it surely occurred during the giant eruptions. This implies that mass transfer can have a huge influence on the evolution of massive stars.

The Formation of Massive Stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311000184 ◽

2010 ◽

Vol 6 (S270) ◽

pp. 57-64

Author(s):

Ian A. Bonnell ◽

Rowan J Smith

Keyword(s):

Star Formation ◽

Magnetic Fields ◽

Massive Star ◽

Massive Stars ◽

Cluster Formation ◽

High Mass ◽

Prestellar Cores ◽

Stellar Mergers ◽

Massive Clusters ◽

Viable Mechanism

AbstractThere has been considerable progress in our understanding of how massive stars form but still much confusion as to why they form. Recent work from several sources has shown that the formation of massive stars through disc accretion, possibly aided by gravitational and Rayleigh-Taylor instabilities is a viable mechanism. Stellar mergers, on the other hand, are unlikely to occur in any but the most massive clusters and hence should not be a primary avenue for massive star formation. In contrast to this success, we are still uncertain as to how the mass that forms a massive star is accumulated. there are two possible mechanisms including the collapse of massive prestellar cores and competitive accretion in clusters. At present, there are theoretical and observational question marks as to the existence of high-mass prestellar cores. theoretically, such objects should fragment before they can attain a relaxed, centrally condensed and high-mass state necessary to form massive stars. Numerical simulations including cluster formation, feedback and magnetic fields have not found such objects but instead point to the continued accretion in a cluster potential as the primary mechanism to form high-mass stars. Feedback and magnetic fields act to slow the star formation process and will reduce the efficiencies from a purely dynamical collapse but otherwise appear to not significantly alter the process.

The UVMag space project: UV and visible spectropolarimetry of massive stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314007212 ◽

2014 ◽

Vol 9 (S307) ◽

pp. 389-390

Author(s):

Coralie Neiner ◽

Keyword(s):

Magnetic Field ◽

High Resolution ◽

Massive Stars ◽

Spectral Energy Distribution ◽

Spectral Energy ◽

Medium Size ◽

Space Project ◽

First Time ◽

The Magnetic Field ◽

Circumstellar Environment

AbstractUVMag is a medium-size space telescope equipped with a high-resolution spectropolarimetrer working in the UV and visible domains. It will be proposed to ESA for a future M mission. It will allow scientists to study all types of stars as well as e.g. exoplanets and the interstellar medium. It will be particularly useful for massive stars, since their spectral energy distribution peaks in the UV. UVMag will allow us to study massive stars and their circumstellar environment (in particular the stellar wind) spectroscopically in great details. Moreover, with UVMag's polarimetric capabilities we will be able, for the first time, to measure the magnetic field of massive stars simultaneously at the stellar surface and in the wind lines, i.e. to completely map their magnetosphere.

Will the Digital Mass Filter Be the Next High-Resolution High-Mass Analyzer?

Journal of the American Society for Mass Spectrometry ◽

10.1021/jasms.1c00234 ◽

2021 ◽

Author(s):

Peter T. A. Reilly ◽

Sumeet Chakravorty ◽

Conner F. Bailey ◽

Fatima O. Obe ◽

Adam P. Huntley

Keyword(s):

High Resolution ◽

High Mass ◽

Mass Analyzer ◽

Mass Filter

High resolution spectroscopy of X-ray emission from high mass X-ray binaries

Advances in Space Research ◽

10.1016/j.asr.2006.04.029 ◽

2006 ◽

Vol 38 (12) ◽

pp. 2737-2741

Author(s):

F. Nagase ◽

S. Watanabe

Keyword(s):

High Resolution ◽

High Resolution Spectroscopy ◽

High Mass ◽

X Ray ◽

X Ray Binaries

Characterizing filaments in regions of high-mass star formation: High-resolution submilimeter imaging of the massive star-forming complex NGC 6334 with ArTéMiS

Astronomy and Astrophysics ◽

10.1051/0004-6361/201628378 ◽

2016 ◽

Vol 592 ◽

pp. A54 ◽

Cited By ~ 43

Author(s):

Ph. André ◽

V. Revéret ◽

V. Könyves ◽

D. Arzoumanian ◽

J. Tigé ◽

...

Keyword(s):

Star Formation ◽

High Resolution ◽

Massive Star ◽

High Mass ◽

Mass Star ◽

Star Forming ◽

Ngc 6334

The B[e] stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100004358 ◽

1989 ◽

Vol 113 ◽

pp. 117-120

Author(s):

F.-J. Zickgraf

Keyword(s):

Physical Properties ◽

Stellar Wind ◽

Main Sequence ◽

Massive Stars ◽

High Mass ◽

Sequence Evolution ◽

Two Component ◽

Show Evidence ◽

High Mass Loss ◽

General Appearance

AbstractB[e] supergiants show evidence for a non-spherical two-component stellar wind. The general appearance and the physical properties of the suggested disk-like configuration are discussed. The high mass-loss rates, the surprisingly large number and the location in the H-R diagram make these stars important for the understanding of the post-main-sequence evolution of massive stars.

The energetic role of massive stars in the AGN phenomenon

Symposium - International Astronomical Union ◽

10.1017/s0074180900206608 ◽

1999 ◽

Vol 193 ◽

pp. 703-715

Author(s):

Timothy M. Heckman

Keyword(s):

Black Holes ◽

Massive Stars ◽

Uv Light ◽

Radiant Energy ◽

Supermassive Black Holes ◽

High Mass ◽

Continuum Emission ◽

Hot Stars

I review the evidence for a possible connection between AGN and starbursts and assess the energetic role of massive stars in the AGN phenomenon. My particular focus is on UV spectroscopy, since this is the energetically dominant spectral regime for the hot high-mass stars that power starbursts, and contains a wealth of spectral features for diagnosing the presence of such stars. I also review the non-stellar sources of UV line and continuum emission in AGN, including scattered or reprocessed light from the ‘central engine’. Spectroscopy directly shows that hot stars provide most of the UV light in about half of the brightest type 2 Seyfert nuclei and UV-bright LINERS. The population of hot stars in these AGN is typically heavily extinct and reddened by dust with A(1600Å) ≃ 2–4 mag. The implied intrinsic UV luminosities of the starburst range from 108 to 109 L⊙ in the LINERS to 1010 to 1011 L⊙ in the type 2 Seyferts. Massive stars play an energetically significant role in many AGN, but the causal or evolution connection between starbursts and AGN is unclear. I also consider the energetics of massive stars and accreting supermassive black holes from a global, cosmic perspective. Recent inventories in the local universe of the cumulative effect of nuclear burning (metal production) and of AGN-fueling (compact dark objects in galactic nuclei) imply that accretion onto supermassive black holes may have produced as much radiant energy as massive stars over the history of the universe.

Observational connections between LBV’s and other stars, with emphasis on Wolf-Rayet stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100004498 ◽

1989 ◽

Vol 113 ◽

pp. 229-240

Author(s):

A. F. J. Moffat ◽

L. Drissen ◽

C. Robert

Keyword(s):

Mass Loss ◽

Massive Stars ◽

Underlying Mechanism ◽

High Mass ◽

Strong Line ◽

Essential Step ◽

High Mass Loss ◽

Loss Rates ◽

R Domain

Abstract.We suggest that the LBV mechanism is an essential step to “force” massive stars (M(ZAMS) ≥ 40M⊙) to finally enter the Wolf-Rayet (W-R) domain in the Hertzsprung-Russel diagram (HRD). Just as massive supergiants showincreasingvariability as theyapproachthe Humphreys-Davidson (H-D)instability limit (horizontally in the HRD diagram), so the W-R stars showdecreasingvariability as theyrecede fromthe H-D limit (at first horizontally into the WNL domain, then, with their high mass loss rates, plunging irreversably downwards as ever hotter, smaller and fainter, strong-line W-R stars). Among the W-R stars, the luminous WNL subtypes (especially WN8) are the most variable, probably as a consequence of blob ejection in the wind. The underlying mechanism which triggers this ejection is possibly related to wind instabilities and may thus be quite different from the source of variability in luminous supergiants or LBV’s in quiescence, where photospheric effects dominate.

Progenitors of early-time interacting supernovae

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1540 ◽

2020 ◽

Vol 496 (2) ◽

pp. 1325-1342 ◽

Cited By ~ 3

Author(s):

Ioana Boian ◽

Jose H Groh

Keyword(s):

Mass Loss ◽

Large Scale ◽

Massive Stars ◽

Early Time ◽

High Mass ◽

Single Star ◽

Circumstellar Material ◽

Wide Range ◽

Wind Velocities ◽

Loss Rates

ABSTRACT We compute an extensive set of early-time spectra of supernovae interacting with circumstellar material using the radiative transfer code cmfgen. Our models are applicable to events observed from 1 to a few days after explosion. Using these models, we constrain the progenitor and explosion properties of a sample of 17 observed interacting supernovae at early times. Because massive stars have strong mass-loss, these spectra provide valuable information about supernova progenitors, such as mass-loss rates, wind velocities, and surface abundances. We show that these events span a wide range of explosion and progenitor properties, exhibiting supernova luminosities in the 108 to 1012 L⊙ range, temperatures from 10 000 to 60 000 K, progenitor mass-loss rates from a few 10−4 up to 1 M⊙ yr−1, wind velocities from 100 to 800 km s−1, and surface abundances from solar-like to H-depleted. Our results suggest that many progenitors of supernovae interacting with circumstellar material have significantly increased mass-loss before explosion compared to what massive stars show during the rest of their lifetimes. We also infer a lack of correlation between surface abundances and mass-loss rates. This may point to the pre-explosion mass-loss mechanism being independent of stellar mass. We find that the majority of these events have CNO-processed surface abundances. In the single star scenario this points to a preference towards high-mass RSGs as progenitors of interacting SNe, while binary evolution could impact this conclusion. Our models are publicly available and readily applicable to analyse results from ongoing and future large-scale surveys such as the Zwicky Transient Factory.