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We present sub-arcsecond optical images and low- to moderate-resolution spectra of the compact, X-ray and optically bright supernova remnant known as S8 in the nearby dwarf galaxy IC 1613. Deep H$alpha$ images of the remnant show a sharply defined crescent shaped nebula, while narrow passband images reveal a coincident and unexpectedly bright continuum nebulosity exhibiting a size and morphology like that seen for the remnants line emissions. Low-dispersion spectra covering 3600 - 9000 A show numerous low-ionization line emissions such as [O I] and [Fe II], along with higher-ionization emission lines including He II and optical coronal lines [Fe VII], [Fe X], [Fe XI], and [Fe XIV]. This suggests the presence of a wide range of shock velocities from $sim$ 50 to over 350 km s$^{-1}$, corresponding to preshock densities of $sim1 - 30$ cm$^{-3}$. Higher resolution spectra indicate an expansion velocity around 180 km s$^{-1}$ with a $sim45$ km s$^{-1}$ wide central cavity. H$alpha$ emission spans rest frame velocities of $+120$ to $-240$ km s$^{-1}$ and we estimate a total nebula mass of $119 pm 34$ M$_{odot}$. We conclude S8 is a relatively young supernova remnant ($simeq2700 - 4400$ yr) exhibiting properties remarkably like those seen in the young LMC remnant N49, including age, physical size, shock velocities, filament densities, optical line strengths, X-ray and optical luminosities, and coronal line and continuum emissions.
We conducted an observation of the nearby irregular galaxy IC 1613 with the Chandra X-ray Observatory using the S3 chip of the ACIS with an effective exposure time of 49.9 ksec. The observation primarily targeted the extensive bubble and star formati
Determining the star formation history (SFH) is key to understand the formation and evolution of dwarf galaxies. Recovering the SFH in resolved galaxies is mostly based on deep colour--magnitude diagrams (CMDs), which trace the signatures of multiple
IC 1613 is a Local Group dwarf irregular galaxy at a distance of 750 kpc. In this work, we present an analysis of the star formation history (SFH) of a field of $sim200$ square arcmin in the central part of the galaxy. To this aim, we use a novel met
Based on observations from the emph{FourStar} near-infrared camera on the 6.5m Baade-Magellan telescope at Las Campanas, Chile, we present calibrations of the $JHK$ luminosities of stars defining the tip of the red giant branch (TRGB) in the halo of
G1.9+0.3 is the youngest known Galactic supernova remnant (SNR), with an estimated supernova (SN) explosion date of about 1900, and most likely located near the Galactic Center. Only the outermost ejecta layers with free-expansion velocities larger t