Dust Grain–Size Distributions and Extinction in the Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud

General aspects of ISM studies using absorption line studies are given and available data are reviewed. Topics are: galactic foreground gas, individual fields in the Magellanic Clouds (MCs) and MC coronae. Overall investigations are discussed. It is demonstrated that the metals in the gas of the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) are a factor of 3 and 10, respectively, in abundance below solar levels. The depletion pattern in the LMC is similar to that of the Milky Way.

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ACTINIUM ABUNDANCES IN STELLAR ATMOSPHERES

Odessa Astronomical Publications ◽

10.18524/1810-4215.2021.34.244288 ◽

2021 ◽

Vol 34 ◽

pp. 70-73

Author(s):

V. Yushchenko ◽

V. Gopka ◽

A.V. Yushchenko ◽

A. Shavrina ◽

Ya. Pavlenkо ◽

...

Keyword(s):

Chemical Evolution ◽

Milky Way ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Stellar Atmospheres ◽

The Other ◽

Small Magellanic Cloud ◽

Red Supergiants ◽

Red Giant

This paper presents a study of radioactive actinium in the atmospheres of stars located in galaxies with different chemical evolution history – namely, Przybylski's Star (HD 101065) in the Milky Way and the red supergiant PMMR27 in the Small Magellanic Cloud; it also reports the findings of the previous research of the red supergiant RM 1-667 in the Large Magellanic Cloud and the red giant BL138 in the Fornax dwarf spheroidal galaxy. The actinium abundance is close to that of uranium in the atmospheres of certain stars in the Milky Way’s halo and in the atmosphere of Arcturus. The following actinium abundances have been obtained (in a scale of lg N(H) = 12): for the red supergiants PMMR27 and RM 1- 667 lg N(Ac) = -1.7 and lg N(Ac) = -1.3, respectively, and for the red giant BL138 lg N(Ac) = -1.6. The actinium abundance in the atmosphere of Przybylski's Star (HD 101065) is lg N(Ac) = `0.94±0.09, which is more than two orders of magnitude higher than those in the atmospheres of the other studied stars.

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Characterising the Protostellar Population of the Magellanic Clouds with VLT/SINFONI

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316008449 ◽

2015 ◽

Vol 11 (S315) ◽

Author(s):

Jacob Ward ◽

Joana Oliveira ◽

Jacco van Loon ◽

Marta Sewilo

Keyword(s):

Star Formation ◽

Milky Way ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Magellanic Clouds ◽

Emission Lines ◽

Young Stellar Objects ◽

Small Magellanic Cloud ◽

Stellar Objects ◽

Accretion Rates

AbstractAt distances of ~50 kpc and ~60 kpc for the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) respectively the Magellanic Clouds present us with a unique opportunity to study star formation in environments outside our own galaxy. Through Spitzer and Herschel photometry and spectroscopy, samples of Young Stellar Objects (YSOs) have been selected and spectroscpically confirmed in the Magellanic Clouds. Here we present some of the key results of our SINFONI K-band observations towards massive YSOs in the Magellanic Clouds. We resolve a number of Spitzer sources into multiple, previously unresolved, components and our analysis of emission lines suggest higher accretion rates and different disc properties compared with massive YSOs in the Milky Way.

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Dust Grain Size Distributions and the Abundance of Refractory Elements in the Diffuse Interstellar Medium

The Astrophysical Journal ◽

10.1086/303903 ◽

1997 ◽

Vol 479 (2) ◽

pp. 806-817 ◽

Cited By ~ 48

Author(s):

James E. O'Donnell ◽

John S. Mathis

Keyword(s):

Grain Size ◽

Interstellar Medium ◽

Size Distributions ◽

Refractory Elements ◽

Grain Size Distributions ◽

Dust Grain

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New Proper Motions of the Small Magellanic Cloud Using HST and Implications for Milky Way Mass

Proceedings of the International Astronomical Union ◽

10.1017/s174392131701078x ◽

2017 ◽

Vol 13 (S334) ◽

pp. 394-395

Author(s):

P. Zivick ◽

N. Kallivayalil ◽

S. Linden ◽

T. Fritz ◽

G. Besla ◽

...

Keyword(s):

Milky Way ◽

Hubble Space Telescope ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Wide Field ◽

Small Magellanic Cloud ◽

Proper Motions ◽

Exact Mass ◽

History Of ◽

Magellanic Stream

AbstractAs new work on the proper motions (PMs) of the Large Magellanic Cloud (LMC) has come out, our view of the history of the Magellanic Clouds has evolved. We now believe they are on their first infall into the Milky Way (MW), having been tidally bound at the start of infall (though not necessarily now). Combining these observations with initial PMs of the Small Magellanic Cloud (SMC) suggests a new formation mechanism of the Magellanic Stream through the stripping of material from the SMC. However, large uncertainties remain in the exact mass of the LMC. We present a measurement of the systemic proper motions of the SMC from astrometry with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST), covering a ~3 year baseline of 30 fields with background QSOs. We find these motions to be μW = −0.82 ± 0.06 mas/yr and μN = −1.23 ± 0.07 mas/yr. Combining these measurements with previous efforts in studying the Clouds will help constrain their interactions with each other and the MW, including the mass of the LMC and the MW, as well as provide new insight into the internal dynamics of the SMC.

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Search for binary central stars of the Magellanic Clouds PNe

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317001892 ◽

2016 ◽

Vol 12 (S323) ◽

pp. 384-385

Author(s):

Marcin Gładkowski ◽

Marcin Hajduk ◽

Igor Soszyński

Keyword(s):

Milky Way ◽

Central Star ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Magellanic Clouds ◽

Small Magellanic Cloud ◽

Photometric Analysis ◽

Gravitational Experiment ◽

The Galaxy ◽

Central Stars

AbstractThe Optical Gravitational Experiment (OGLE) was effectively used in discovering binary central stars of planetary nebulae (CSPNe). About 50 binary CSPNe have been hitherto identified in the Galaxy, almost half of them were detected in the OGLE database. We used the OGLE data to search for binary CSPNe in the Magellanic Clouds. We also searched for PNe mimics and removed them from the PNe sample. Here, we present results of the photometric analysis for Small Magellanic Cloud (SMC) and our progress on search of binary central stars in the Large Magellanic Cloud (LMC). So far, we have discovered one binary central star of the PN beyond the Milky Way, which is located in the Small Magellanic Cloud.

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Evolution of the grain size distribution in Milky Way-like galaxies in post-processed IllustrisTNG simulations

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3695 ◽

2020 ◽

Vol 501 (1) ◽

pp. 1336-1351

Author(s):

Yu-Hsiu Huang ◽

Hiroyuki Hirashita ◽

Yun-Hsin Hsu ◽

Yen-Ting Lin ◽

Dylan Nelson ◽

...

Keyword(s):

Grain Size ◽

Size Distribution ◽

Grain Size Distribution ◽

Milky Way ◽

Extinction Curve ◽

Size Distributions ◽

Grain Size Distributions ◽

Nearby Galaxies ◽

Hydrodynamical Simulations ◽

Dust Evolution

ABSTRACT We model dust evolution in Milky Way-like galaxies by post-processing the IllustrisTNG cosmological hydrodynamical simulations in order to predict dust-to-gas ratios and grain size distributions. We treat grain-size-dependent dust growth and destruction processes using a 64-bin discrete grain size evolution model without spatially resolving each galaxy. Our model broadly reproduces the observed dust–metallicity scaling relation in nearby galaxies. The grain size distribution is dominated by large grains at z ≳ 3 and the small-grain abundance rapidly increases by shattering and accretion (dust growth) at z ≲ 2. The grain size distribution approaches the so-called MRN distribution at z ∼ 1, but a suppression of large-grain abundances occurs at z < 1. Based on the computed grain size distributions and grain compositions, we also calculate the evolution of the extinction curve for each Milky Way analogue. Extinction curves are initially flat at z > 2, and become consistent with the Milky Way extinction curve at z ≲ 1 at $1/\lambda \lt 6~\rm{\mu m}^{-1}$. However, typical extinction curves predicted by our model have a steeper slope at short wavelengths than is observed in the Milky Way. This is due to the low-redshift decline of gas-phase metallicity and the dense gas fraction in our TNG Milky Way analogues that suppresses the formation of large grains through coagulation.

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