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تسجيل مستخدم جديدThe intrinsic reddening of the Magellanic Clouds as traced by background galaxies -- II. The Small Magellanic Cloud
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We present a map of the total intrinsic reddening across ~34 deg$^{2}$ of the Small Magellanic Cloud (SMC) derived using optical ($ugriz$) and near-infrared (IR; $YJK_{mathrm{s}}$) spectral energy distributions (SEDs) of background galaxies. The reddening map is created using a subsample of 29,274 galaxies with low levels of intrinsic reddening based on the LePhare $chi^{2}$ minimisation SED-fitting routine. We find statistically significant enhanced levels of reddening associated with the main body of the SMC compared with regions in the outskirts [$Delta E(B-V)simeq 0.3$ mag]. A comparison with literature reddening maps of the SMC shows that, after correcting for differences in the volume of the SMC sampled, there is good agreement between our results and maps created using young stars. In contrast, we find significant discrepancies between our results and maps created using old stars or based on longer wavelength far-IR dust emission that could stem from biased samples in the former and uncertainties in the far-IR emissivity and the optical properties of the dust grains in the latter. This study represents one of the first large-scale categorisations of extragalactic sources behind the SMC and as such we provide the LePhare outputs for our full sample of ~500,000 sources.
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We present a method to map the total intrinsic reddening of a foreground extinguishing medium via the analysis of spectral energy distributions (SEDs) of background galaxies. In this pilot study, we implement this technique in two distinct regions of
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Feedback from massive stars plays a critical role in the evolution of the Universe by driving powerful outflows from galaxies that enrich the intergalactic medium and regulate star formation. An important source of outflows may be the most numerous g
alaxies in the Universe: dwarf galaxies. With small gravitational potential wells, these galaxies easily lose their star-forming material in the presence of intense stellar feedback. Here, we show that the nearby dwarf galaxy, the Small Magellanic Cloud (SMC), has atomic hydrogen outflows extending at least 2 kiloparsecs (kpc) from the star-forming bar of the galaxy. The outflows are cold, $T<400~{rm K}$, and may have formed during a period of active star formation $25 - 60$ million years (Myr) ago. The total mass of atomic gas in the outflow is $sim 10^7$ solar masses, ${rm M_{odot}}$, or $sim 3$% of the total atomic gas of the galaxy. The inferred mass flux in atomic gas alone, $dot{M}_{HI}sim 0.2 - 1.0~{rm M_{odot}~yr^{-1}}$, is up to an order of magnitude greater than the star formation rate. We suggest that most of the observed outflow will be stripped from the SMC through its interaction with its companion, the Large Magellanic Cloud (LMC), and the Milky Way, feeding the Magellanic Stream of hydrogen encircling the Milky Way.
We present reddening maps of the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC), based on color measurements of the red clump. Reddening values of our maps were obtained by calculating the difference of the observed and intrinsic color
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We present a high-sensitivity ($1sigma<1.6~mathrm{mJy~beam^{-1}}$) continuum observation in a 343 arcmin$^2$ area of the northeast region in the Small Magellanic Cloud at a wavelength of 1.1 mm, conducted using the AzTEC instrument on the ASTE telesc
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