The Dark Energy Camera Magellanic Clouds Emission-Line Survey

Abstract

We have used the Dark Energy Camera (DECam) on the CTIO Blanco 4-m telescope to perform a new emission-line survey of the Large Magellanic Cloud (LMC) using narrow-band H-alpha and [SII] filters in addition to a continuum band for use in creating pure emission-line images. We refer to this new survey as DeMCELS, to distinguish it from the earlier Magellanic Cloud Emission Line Survey (MCELS) that has been in service for nearly 25 years. DeMCELS covers $\sim 54$ degrees${}^2$, encompassing most of the bright optical disk of the LMC. With DECam's pixel size of only 0.27", our DeMCELS survey provides a seeing-limited improvement of 3-5 times over MCELS and is comparable in depth, with surface brightness limits of 3.3E-17 erg cm${}^{-2}$ s${}^{-1}$ arcsec${}^{-2}$ in H-alpha and 2.9E-17 erg cm${}^{-2}$ s${}^{-1}$ arcsec${}^{-2}$ in H-alpha and [SII], respectively. DeMCELS provides detailed morphological information on nebulae of all scales, from the largest supershells to individual [HII] regions and supernova remnants, to bubbles of emission surrounding individual stars, and even to faint structures in the diffuse ionized gas of the LMC. Many complex regions of emission show significant variations in the ratio of [SII] to H-alpha, a sign of the mixture of shocks from stellar winds and/or supernovae with photoionization by embedded hot, young stars. We present the details of the observing strategy and data processing for this survey, and show selected results in comparison with previous data. A companion project for the Small Magellanic Cloud is in progress and will be reported separately. We are making these new data available to the community at large via the NOIRLab's Data Lab site.

30 pages, 16 figures Accepted for publication (ApJ)

References in corpus (35)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• Astropy: A Community Python Package for Astronomy
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• The Dark Energy Camera
• Spitzer Survey of the Large Magellanic Cloud, Surveying the Agents of a Galaxy's Evolution (SAGE) I: Overview and Initial Results
• A distance to the Large Magellanic Cloud that is precise to one per cent
• The Star Formation History of the Large Magellanic Cloud
• The warm ionized medium in spiral galaxies
• The Optical Depth of H II Regions in the Magellanic Clouds
• The population of X-ray supernova remnants in the Large Magellanic Cloud
• Measuring the Mass of the Large Magellanic Cloud with Stellar Streams Observed by $S^5$
• Statistical Analysis of Supernova Remnants in the Large Magellanic Cloud
• X-Rays from Superbubbles in the Large Magellanic Cloud. VI. A Sample of Thirteen Superbubbles
• A New Population of Planetary Nebulae Discovered in the Large Magellanic Cloud (II): Complete PN Catalogue
• Calibration of Nebular Emission-Line Diagnostics: I. Stellar Effective Temperatures
• Hubble Space Telescope Images of Magellanic Cloud Planetary Nebulae
• The VMC survey -- XLIV: Mapping metallicity trends in the Large Magellanic Cloud using near-infrared passbands
• XMM-Newton study of 30 Dor C and a newly identified MCSNR J0536-6913 in the Large Magellanic Cloud
• The HI Environment of Three Superbubbles in the Large Magellanic Cloud
• New Optically Identified Supernova Remnants in the Large Magellanic Cloud
• Far Ultraviolet Spectroscopic Explorer Survey of Magellanic Cloud Supernova Remnants
• Multi-Frequency Study of Supernova Remnants in the Large Magellanic Cloud. The case of LMC SNR J0530-7007
• Multi-frequency study of Local Group Supernova Remnants The curious case of the Large Magellanic Cloud SNR J0528-6714
• Supernova Remnants in M83 as Observed with MUSE
• A New Population of Planetary Nebulae Discovered in the Large Magellanic Cloud (IV): The Outer LMC
• Possible Detection of OVI from the LMC Superbubble N70
• Multi-frequency study of DEM L299 in the Large Magellanic Cloud
• Tracking down the origin of superbubbles and supergiant shells in the Magellanic Clouds with Minkowski tensor analysis
• New ASKAP Radio Supernova Remnants and Candidates in the Large Magellanic Cloud
• A Multiwavelength Survey of Wolf-Rayet Nebulae in the Large Magellanic Cloud
• Multi-frequency study of the newly confirmed supernova remnant MCSNR J0512-6707 in the Large Magellanic Cloud
• Towards an explanation for the 30 Dor (LMC) Honeycomb nebula - the impact of recent observations and spectral analysis
• Physical Nature of the [S II]-Bright Shell Nebulae N70 and N185

Cited by in corpus (2)

• Current Unsolved Problems in Planetary Nebulae Research
• LMC+: Large-scale mapping of [CII] and [OIII] in the LMC molecular ridge, I. Dataset and line ratio analyses