A Second Compact Radio Component Detected in the LMC HII Region N159

AbstractThe Australia Telescope Compact Array has been used for observations, with arcsecond resolution, of the HII region N159 in the Large Magellanic Cloud. Images at 5 GHz reveal a second compact continuum component which has no obvious counterpart at optical and infrared wavelengths. Observations of HI 10α recombination-line emission, and HI and H2CO absorption, suggest that the object is a compact HII region embedded in a dense obscuring cloud on the edge of N159.

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An HI Mosaic of the Large Magellanic Cloud

Publications of the Astronomical Society of Australia ◽

10.1071/as97119 ◽

1997 ◽

Vol 14 (1) ◽

pp. 119-121 ◽

Cited By ~ 14

Author(s):

Sungeun Kim ◽

K. C. Freeman ◽

L. Staveley-Smith ◽

R. J. Sault ◽

M. J. Kesteven ◽

...

Keyword(s):

Brightness Temperature ◽

Neutral Hydrogen ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Compact Array

AbstractThe parameters of a new Australia Telescope Compact Array (ATCA) mosaic of the Large Magellanic Cloud (LMC) in the 21-cm line of neutral hydrogen are described. A preliminary peak-brightness-temperature image of the whole of the LMC, and a detailed image of the region around the supergiant shells LMC 4 and 5 is shown.

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The HI Supergiant Shells in the Large Magellanic Cloud

International Astronomical Union Colloquium ◽

10.1017/s0252921100071542 ◽

1997 ◽

Vol 166 ◽

pp. 521-524

Author(s):

S. Kim ◽

L. Staveley-Smith ◽

R.J. Sault ◽

M.J. Kesteven ◽

D. McConnell ◽

...

Keyword(s):

Differential Rotation ◽

Spiral Structure ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Aperture Synthesis ◽

Wide Field ◽

Combined Action ◽

Compact Array

AbstractWe present the result of an HI aperture synthesis mosaic of the Large Magellanic cloud (LMC), made recently with the Australia Telescope Compact Array (ATCA). The resolution of the mosaiced images is l′.0 (15 pc, using a distance to the LMC of 50 kpc). In contrast to its appearance at other wavelengths, the LMC is remarkably symmetrical in HI on the largest scales, with the bulk of the HI residing in a disk of diameter 8.°4 (7.3 kpc). Outer spiral structure is clearly seen, though the features appear to be due to differential rotation, therefore transient in nature. On small to medium scales, the combined action of numerous shells and supershells dominate the structures and motions of the HI gas in the LMC. A good correlation is seen between supershells previously identified in Hα (e.g. Meaburn 1980) and HI structures. We compare the results with a new wide-field Hα image.

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The 100 strongest radio point sources in the field of the Large Magellanic Cloud at 1.4 GHz

Serbian Astronomical Journal ◽

10.2298/saj0978065p ◽

2009 ◽

pp. 65-70 ◽

Cited By ~ 2

Author(s):

J.L. Payne ◽

L.A. Tauber ◽

M.D. Filipovic ◽

E.J. Crawford ◽

Horta de

Keyword(s):

Spectral Index ◽

Planetary Nebulae ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Point Sources ◽

H Ii Regions ◽

Short Spacing ◽

Mosaic Image ◽

Initial List ◽

Compact Array

We present the 100 strongest 1.4 GHz point sources from a new mosaic image in the direction of the Large Magellanic Cloud (LMC). The observations making up the mosaic were made using Australia Telescope Compact Array (ATCA) over a ten year period and were combined with Parkes single dish data at 1.4 GHz to complete the image for short spacing. An initial list of co-identifications within 1000 at 0.843, 4.8 and 8.6 GHz consisted of 2682 sources. Elimination of extended objects and artifact noise allowed the creation of a refined list containing 1988 point sources. Most of these are presumed to be background objects seen through the LMC; a small portion may represent compact H ii regions, young SNRs and radio planetary nebulae. For the 1988 point sources we find a preliminary average spectral index (?) of -0.53 and present a 1.4 GHz image showing source location in the direction of the LMC.

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Multifrequency radio observations of a SNR in the LMC: The case of SNR J0527-6549 (DEM l204)

Serbian Astronomical Journal ◽

10.2298/saj1081043b ◽

2010 ◽

pp. 43-49 ◽

Cited By ~ 12

Author(s):

L.M. Bozzetto ◽

M.D. Filipovic ◽

E.J. Crawford ◽

I.S. Bojicic ◽

J.L. Payne ◽

...

Keyword(s):

Spectral Index ◽

Supernova Remnant ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

High Order ◽

Older Age ◽

Radio Observations ◽

Large Size ◽

Peak Value ◽

Compact Array

We present a detailed study and results of new Australia Telescope Compact Array (ATCA) observations of supernova remnant SNR J0527-6549. This Large Magellanic Cloud (LMC) object follows a typical supernova remnant (SNR) horseshoe morphology with a diameter of D=(66?58)?1 pc which is among the largest SNRs in the LMC. Its relatively large size indicates older age while a steeper than expected radio spectral index of ?=-0.92?0.11 is more typical of younger and energetic SNRs. Also, we report detections of regions with a high order of polarization at a peak value of ~54%?17% at 6 cm.

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Velocity profiles of [CII], [CI], CO, and [OI] and physical conditions in four star-forming regions in the Large Magellanic Cloud

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833398 ◽

2019 ◽

Vol 621 ◽

pp. A62 ◽

Cited By ~ 9

Author(s):

Yoko Okada ◽

Rolf Güsten ◽

Miguel Angel Requena-Torres ◽

Markus Röllig ◽

Jürgen Stutzki ◽

...

Keyword(s):

Physical Properties ◽

High Redshift ◽

Line Emission ◽

Chemical Species ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Continuum Emission ◽

Line Profiles ◽

Star Forming ◽

Star Forming Regions

Aims. The aim of our study is to investigate the physical properties of the star-forming interstellar medium (ISM) in the Large Magellanic Cloud (LMC) by separating the origin of the emission lines spatially and spectrally. The LMC provides a unique local template to bridge studies in the Galaxy and high redshift galaxies because of its low metallicity and proximity, enabling us to study the detailed physics of the ISM in spatially resolved individual star-forming regions. Following Okada et al. (Okada, Y., Requena-Torres, M. A., Güsten, R., et al. 2015, A&A, 580, A54), we investigate different phases of the ISM traced by carbon-bearing species in four star-forming regions in the LMC, and model the physical properties using the KOSMA-τ PDR model. Methods. We mapped 3–13 arcmin2 areas in 30 Dor, N158, N160, and N159 along the molecular ridge of the LMC in [C II] 158 μm with GREAT on board SOFIA. We also observed the same area with CO(2-1) to (6-5), 13CO(2-1) and (3-2), [C I] 3P1–3P0 and 3P2–3P1 with APEX. For selected positions in N159 and 30 Dor, we observed [O I] 145 μm and [O I] 63 μm with upGREAT. All spectra are velocity resolved. Results. In all four star-forming regions, the line profiles of CO, 13CO, and [C I] emission are similar, being reproduced by a combination of Gaussian profiles defined by CO(3-2), whereas [C II] typically shows wider line profiles or an additional velocity component. At several positions in N159 and 30 Dor, we observed the velocity-resolved [O I] 145 and 63 μm lines for the first time. At some positions, the [O I] line profiles match those of CO, at other positions they are more similar to the [C II] profiles. We interpret the different line profiles of CO, [C II] and [O I] as contributions from spatially separated clouds and/or clouds in different physical phases, which give different line ratios depending on their physical properties. We modeled the emission from the CO, [C I], [C II], and [O I] lines and the far-infrared continuum emission using the latest KOSMA-τ PDR model, which treats the dust-related physics consistently and computes the dust continuum SED together with the line emission of the chemical species. We find that the line and continuum emissions are not well-reproduced by a single clump ensemble. Toward the CO peak at N159 W, we propose a scenario that the CO, [C II], and [O I] 63 μm emission are weaker than expected because of mutual shielding among clumps.

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Multifrequency observations of one of the largest supernova remnants in the local group of galaxies, LMC - SNR J0450-709

Serbian Astronomical Journal ◽

10.2298/saj0979055c ◽

2009 ◽

pp. 55-60 ◽

Cited By ~ 19

Author(s):

K.O. Cajko ◽

E.J. Crawford ◽

M.D. Filipovic

Keyword(s):

Spectral Index ◽

Supernova Remnants ◽

Supernova Remnant ◽

Local Group ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

High Polarization ◽

Typical Morphology ◽

Peak Value ◽

Compact Array

We present the results of new Australia Telescope Compact Array (ATCA) observations of one of the largest supernova remnants, SNR J0450-709, in the Local Group of galaxies. We found that this Large Magellanic Cloud (LMC) object exhibits a typical morphology of an old supernova remnant (SNR) with diameter D=102x75?1 pc and radio spectral index ?=-0.43?0.06. Regions of high polarization were detected with peak value of ~40%.

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An Australia Telescope Compact Array 20-cm radio continuum study of the Large Magellanic Cloud

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2007.12466.x ◽

2007 ◽

Vol 382 (2) ◽

pp. 543-552 ◽

Cited By ~ 64

Author(s):

A. Hughes ◽

L. Staveley-Smith ◽

S. Kim ◽

M. Wolleben ◽

M. Filipovic

Keyword(s):

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Radio Continuum ◽

Compact Array

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Reddening map and recent star formation in the Magellanic Clouds based on OGLE IV Cepheids

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834574 ◽

2019 ◽

Vol 628 ◽

pp. A51 ◽

Cited By ~ 3

Author(s):

Y. C. Joshi ◽

A. Panchal

Keyword(s):

Star Formation ◽

Large Data ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Star Formation History ◽

Heterogeneous Distribution ◽

Hii Region ◽

Star Forming ◽

Spatio Temporal ◽

Age Relations

Context. The reddening maps of the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) are constructed using the Cepheid period–luminosity (P–L) relations. Aims. We examine reddening distribution across the LMC and SMC through large data sets on classical Cepheids provided by the OGLE Phase IV survey. We also investigate the age and spatio-temporal distributions of Cepheids to understand the recent star formation history in the LMC and SMC. Methods. The V and I band photometric data of 2476 fundamental mode (FU) and 1775 first overtone mode (FO) Cepheids in the LMC, and 2753 FU and 1793 FO Cepheids in the SMC were analysed for their P–L relations. We converted the period of FO Cepheids to the corresponding period of FU Cepheids before combining the two modes of Cepheids. Both galaxies were divided into small segments and combined FU and FO P–L diagrams were drawn in two bands for each segment. The reddening analysis was performed on 133 segments covering a total area of about 154.6 deg2 in the LMC and 136 segments covering a total area of about 31.3 deg2 in the SMC. By comparison with well-calibrated P–L relations of these two galaxies, we determined reddening E(V − I) in each segment and equivalent reddening E(B − V) assuming the normal extinction law. The period–age relations were used to derive the age of the Cepheids. Results. Reddening maps were constructed using reddening values in different segments across the LMC and SMC. We find clumpy structures in the reddening distributions of the LMC and SMC. From the reddening map of the LMC, highest reddening of E(V − I) = 0.466 mag is traced in the region centred at α ∼ 85.°13, δ ∼ −69.°34 which is in close vicinity of the star forming HII region 30 Doradus. In the SMC, maximum reddening of E(V − I) = 0.189 mag is detected in the region centred at α ∼ 12.°10, δ ∼ −73.°07. The mean reddening values in the LMC and SMC are estimated as E(V − I)LMC = 0.113 ± 0.060 mag, E(B − V)LMC = 0.091 ± 0.050 mag, E(V − I)SMC = 0.049 ± 0.070 mag, and E(B − V)SMC = 0.038 ± 0.053 mag. Conclusions. The LMC reddening map displays heterogeneous distribution having small reddening in the central region and higher reddening towards the eastern side of the LMC bar. The SMC has relatively small reddening in its peripheral regions but larger reddening towards the south-west region. In these galaxies, we see evidence of a common enhanced Cepheid population at around 200 Myr ago which appears to have occurred due to a close encounter between the two clouds.

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An HI Aperture Synthesis Mosaic Survey of the Large Magellanic Cloud

Symposium - International Astronomical Union ◽

10.1017/s0074180900117486 ◽

1999 ◽

Vol 190 ◽

pp. 101-102

Author(s):

Sungeun Kim ◽

L. Staveley-Smith ◽

R. J. Sault ◽

M. A. Dopita ◽

K. C. Freeman ◽

...

Keyword(s):

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Aperture Synthesis ◽

Combining Data ◽

Compact Array

We present the results of an HI aperture synthesis mosaic of the Large Magellanic Cloud (LMC), made by combining data from 1344 separate pointing centers using the Australia Telescope Compact Array (ATCA). The resolution of the mosaiced image is 1′ (15 pc, using a distance to the LMC of 50 kpc).

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