MALT90: The Millimetre Astronomy Legacy Team 90 GHz Survey

Abstract

The Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey aims to characterise the physical and chemical evolution of high-mass star-forming clumps. Exploiting the unique broad frequency range and on-the-fly mapping capabilities of the Australia Telescope National Facility Mopra 22 m single-dish telescope, MALT90 has obtained 3' x 3' maps toward ~2000 dense molecular clumps identified in the ATLASGAL 870 um Galactic plane survey. The clumps were selected to host the early stages of high-mass star formation and to span the complete range in their evolutionary states (from prestellar, to protostellar, and on to HII regions and photodissociation regions). Because MALT90 mapped 16 lines simultaneously with excellent spatial (38") and spectral (0.11 km/s) resolution, the data reveal a wealth of information about the clump's morphologies, chemistry, and kinematics. In this paper we outline the survey strategy, observing mode, data reduction procedure, and highlight some early science results. All MALT90 raw and processed data products are available to the community. With its unprecedented large sample of clumps, MALT90 is the largest survey of its type ever conducted and an excellent resource for identifying interesting candidates for high resolution studies with ALMA.

Accepted to PASA, 13 pages

References in corpus (7)

• Theory of Star Formation
• Cold Dark Clouds: The Initial Conditions for Star Formation
• Ethynyl (C2H) in massive star formation: Tracing the initial conditions?
• Chemical Evolution in High-Mass Star-Forming Regions: Results from the MALT90 Survey
• Distinct Chemical Regions in the "Prestellar" Infrared Dark Cloud (IRDC) G028.23-00.19
• Characterization of the MALT90 Survey and the Mopra Telescope at 90 GHz
• Physical and chemical conditions in methanol maser selected hot-cores and UCHII regions

Cited by in corpus (119)

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• The ATLASGAL survey: a catalog of dust condensations in the Galactic plane
• The ALMA Survey of 70 $\mu$m dark High-mass clumps in Early Stages (ASHES). I. Pilot Survey: Clump Fragmentation
• The Origin of Massive Stars: The Inertial-Inflow Model
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• A Massive Prestellar Clump Hosting no High-Mass Cores
• SEDIGISM: Structure, excitation, and dynamics of the inner Galactic interstellar medium
• Far-Infrared Dust Temperatures and Column Densities of the MALT90 Molecular Clump Sample
• A cluster in the making: ALMA reveals the initial conditions for high-mass cluster formation
• ATLASGAL -- A Galaxy-wide sample of dense filamentary structures
• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- I. Survey description and a first look at G9.62+0.19
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• 'The Brick' is not a brick: A comprehensive study of the structure and dynamics of the Central Molecular Zone cloud G0.253+0.016
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• The Physical Properties of Large-Scale Galactic Filaments
• Characterizing filaments in regions of high-mass star formation: High-resolution submilimeter imaging of the massive star-forming complex NGC 6334 with ArTéMiS
• The Skeleton of the Milky Way
• The dynamical evolution of molecular clouds near the Galactic Centre - II. Spatial structure and kinematics of simulated clouds
• ATLASGAL -- Evolutionary trends in high-mass star formation
• Infall Signatures in a Prestellar Core embedded in the High-Mass 70 $\mu$m Dark IRDC G331.372-00.116
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• The Hi-GAL catalogue of dusty filamentary structures in the Galactic Plane
• G0.253+0.016: A centrally condensed, high-mass protocluster
• Ubiquitous velocity fluctuations throughout the molecular interstellar medium
• Giant molecular filaments in the Milky Way II: The fourth Galactic quadrant
• The ALMA Survey of 70 $\mu$m Dark High-mass Clumps in Early Stages (ASHES). IX. Physical Properties and Spatial Distribution of Cores in IRDCs
• Tracing the Conversion of Gas into Stars in Young Massive Cluster Progenitors
• Infall Motions in Massive Star-Forming Regions: Results from Years 1 & 2 of the MALT90 Survey
• Bipolar HII regions - Morphology and star formation in their vicinity - I - G319.88$+$00.79 and G010.32$-$00.15
• The ALMA Survey of 70 $\mu \mathrm{m}$ Dark High-mass Clumps in Early Stages (ASHES). II: Molecular Outflows in the Extreme Early Stages of Protocluster Formation
• A MALT90 study of the chemical properties of massive clumps and filaments of infrared dark clouds
• Distinguishing models of reionization using future radio observations of 21-cm 1-point statistics
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• Chemical complexity in high-mass star formation: An observational and modeling case study of the AFGL 2591 VLA 3 hot core
• Linking Dense Gas from the Milky Way to External Galaxies
• Characterizing the properties of cluster precursors in the MALT90 survey
• Feedback from OB stars on their parent cloud: Gas exhaustion rather than gas ejection
• The Bolocam Galactic Plane Survey. XII. Distance Catalog Expansion Using Kinematic Isolation of Dense Molecular Cloud Structures With 13CO(1-0)
• Continuum sources from the THOR survey between 1 and 2 GHz
• Characterizing the line emission from molecular clouds. Stratified random sampling of the Perseus cloud
• Distributed Low-Mass Star Formation in the IRDC G34.43+00.24
• H2O Southern Galactic Plane Survey (HOPS): Paper III - Properties of Dense Molecular Gas across the Inner Milky Way
• Direct observational evidence of the multi-scale, dynamical mass accretion toward a high-mass star forming hub-filament system
• The ALMA Survey of 70 μm Dark High-mass Clumps in Early Stages (ASHES). VIII. Dynamics of Embedded Dense Cores
• Massive 70 micron quiet clumps I: evidence of embedded low/intermediate-mass star formation activity
• HP2 survey: III The California Molecular Cloud--A Sleeping Giant Revisited
• High-mass Starless Clumps in the inner Galactic Plane: the Sample and Dust Properties
• Star formation in 'the Brick': ALMA reveals an active proto-cluster in the Galactic centre cloud G0.253+0.016
• Survey Observations to Study Chemical Evolution from High-mass Starless Cores to High-mass Protostellar Objects I: HC3N and HC5N
• HII regions and high-mass starless clump candidates II. Fragmentation and induced star formation at ~0.025 pc scale: An ALMA continuum study
• SEDIGISM-ATLASGAL: Dense Gas Fraction and Star Formation Efficiency Across the Galactic Disk
• The SQUALO project (Star formation in QUiescent And Luminous Objects) I: clump-fed accretion mechanism in high-mass star-forming objects
• Asymmetric Line Profiles in Dense Molecular Clumps Observed in MALT90: Evidence for Global Collapse
• ATLASGAL --- Molecular fingerprints of a sample of massive star forming clumps
• Properties of massive star-forming clumps with infall motions
• Contamination of the Epoch of Reionization power spectrum in the presence of foregrounds
• ATLASGAL - Ammonia observations towards the southern Galactic Plane
• The Galactic Census of High- and Medium-mass Protostars. IV. Molecular Clump Radiative Transfer, Mass Distributions, Kinematics, and Dynamical Evolution
• ALMA observations of RCW 120 Fragmentation at 0.01pc scale
• Lack of high-mass prestellar cores in the starless MDCs of NGC6334
• Survey Observations to Study Chemical Evolution from High-Mass Starless Cores to High-Mass Protostellar Objects II. HC${}_3$N and N${}_2$H${}^{+}$
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• A Complete HCN Survey of the Perseus Molecular Cloud
• The ALMA Survey of 70$\mu$m Dark High-mass Clumps in Early Stages (ASHES) III. A Young Molecular Outflow Driven by a Decelerating Jet
• The Galactic Census of High- and Medium-mass Protostars. III ${}^{12}$CO Maps and Physical Properties of Dense Clump Envelopes and their Embedding GMCs
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• Probing the massive star forming environment - a multiwavelength investigation of the filamentary IRDC G333.73+0.37
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• Infrared dark clouds on the far side of the Galaxy
• Initial phases of high-mass star formation: A multiwavelength study towards the extended green object G12.42+0.50
• Searching for Inflow Towards Massive Starless Clump Candidates Identified in the Bolocam Galactic Plane Survey
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• An International Survey of Front-End Receivers and Observing Performance of Telescopes for Radio Astronomy
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• Physical Properties of Galactic Planck Cold Cores revealed by the Hi-GAL survey
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