The initial conditions of star formation VIII: an observational study of the Ophiuchus cloud L1688 and implications for the prestellar core mass function

Abstract

We re-analyse all of the archive observations of the Ophiuchus dark cloud L1688 that were carried out with the submillimetre common-user bolometer array (SCUBA) at the James Clerk Maxwell Telescope (JCMT). For the first time we put together all of the data that were taken of this cloud at different times to make a deeper map at 850 microns than has ever previously been published. Using this new, deeper map we extract the pre-stellar cores from the data. We use updated values for the distance to the cloud complex, and also for the internal temperatures of the pre-stellar cores to generate an updated core mass function (CMF). This updated CMF is consistent with previous results in so far as they went, but our deeper map gives an improved completeness limit of 0.1 Mo (0.16 Jy), which enables us to show that a turnover exists in the low-mass regime of the CMF. The L1688 CMF shows the same form as the stellar IMF and can be mapped onto the stellar IMF, showing that the IMF is determined at the prestellar core stage. We compare L1688 with the Orion star-forming region and find that the turnover in the L1688 CMF occurs at a mass roughly a factor of two lower than the CMF turnover in Orion. This suggests that the position of the CMF turnover may be a function of environment.

arXiv comment11 Pages. Accepted by MNRAS

References in corpus (22)

• Galactic Stellar and Substellar Initial Mass Function
• The Initial Mass Function of Stars: Evidence for Uniformity in Variable Systems
• The SCUBA Legacy Catalogue: Continuum Objects Detected by SCUBA
• Star formation in clusters: a survey of compact mm-wave sources in the Serpens core
• The Mass Distribution and Lifetime of Prestellar Cores in Perseus, Serpens, and Ophiuchus
• Star formation in Perseus - V. Outflows detected by HARP
• The initial conditions of isolated star formation - VI. SCUBA mapping of prestellar cores
• A SCUBA survey of Orion, the low-mass end of the core mass function
• An Extinction Threshold for Protostellar Cores in Ophiuchus
• A SCUBA survey of the NGC 2068/2071 protoclusters
• The James Clerk Maxwell Telescope Legacy Survey of Nearby Star-forming Regions in the Gould Belt
• An unbiased search for the signatures of protostars in the rho Ophiuchi Molecular Cloud. II. Millimetre continuum observations
• Current Star Formation in the Ophiuchus and Perseus Molecular Clouds: Constraints and Comparisons from Unbiased Submillimeter and Mid-Infrared Surveys. II
• On the Distance to the Ophiuchus Star-Forming Region
• Large Area Mapping at 850 Microns. IV. Analysis of the Clump Distribution in the Orion B South Molecular Cloud
• The relationship between the prestellar core mass function and the stellar initial mass function
• A SCUBA survey of L1689 - The dog that didn't bark
• On the atmospheric limitations of ground-based submillimetre astronomy using array receivers
• The dust temperatures of the prestellar cores in the rho Oph main cloud and in other star forming regions: consequences for the core mass function
• On the Evolution of the Dense Core Mass Function
• The initial conditions of isolated star formation: IV - C18O observations and modelling of the pre-stellar core L1689B
• An explanation for the unusual IMF in Taurus

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• Global Hierarchical Collapse In Molecular Clouds. Towards a Comprehensive Scenario
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• A census of dense cores in the Taurus L1495 cloud from the Herschel Gould Belt Survey
• Radiation Feedback, Fragmentation, and the Environmental Dependence of the Initial Mass Function
• Formation of Magnetized Prestellar Cores with Ambipolar Diffusion and Turbulence
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• Fragmentation in Molecular Clouds and its connection to the IMF
• The Dust Emissivity Spectral Index in the Starless Core TMC-1C
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• Looking into the hearts of Bok globules: MM and submm continuum images of isolated star-forming cores
• Simultaneous low- and high-mass star formation in a massive protocluster: ALMA observations of G11.92-0.61
• An Observed Lack of Substructure in Starless Cores
• The Initial Conditions of Clustered Star Formation. II. N2H+ Observations of the Ophiuchus B Core
• The JCMT Legacy Survey of the Gould Belt: a molecular line study of the Ophiuchus molecular cloud
• Physical Properties of Dense Cores in the Rho Ophiuchi Main Cloud and A Significant Role of External Pressures in Clustered Star Formation
• The influence of the turbulent perturbation scale on prestellar core fragmentation and disk formation
• Simulating star formation in Ophiuchus
• Star formation: statistical measure of the correlation between the prestellar core mass function and the stellar initial mass function
• SCOPE: SCUBA-2 Continuum Observations of Pre-protostellar Evolution - Survey Description and Compact Source Catalogue
• On the fidelity of the core mass functions derived from dust column density data
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• A Hi-GAL study of the high-mass star-forming region G29.96-0.02
• The properties of SCUBA cores in the Perseus molecular cloud: the bias of clump-finding algorithms
• The JCMT Gould Belt Survey: First results from SCUBA-2 observations of the Cepheus Flare Region
• The Initial Core Mass Function due to Ambipolar Diffusion in Molecular Clouds
• Mapping the core mass function onto the stellar IMF: multiplicity matters
• Deuterium Fractionation in the Ophiuchus Molecular Cloud
• Prestellar and protostellar cores in Ori B9
• Initial conditions for star formation in clusters: physical and kinematical structure of the starless core Oph A-N6
• Forming isolated brown dwarfs by turbulent fragmentation
• What does a universal IMF imply about star formation?
• The Thermodynamics of Molecular Cloud Fragmentation: Star Formation Under Non-Milky Way Conditions
• The initial conditions of isolated star formation - X. A suggested evolutionary diagram for prestellar cores
• The initial conditions of isolated star formation -- IX. Akari mapping of an externally heated pre-stellar core
• The immediate environment of the Class 0 protostar VLA1623, on scales of ~50-100 AU, observed at millimetre and centimetre wavelengths
• The intrinsic shapes of starless cores in Ophiuchus
• CO Core Candidates in the Gemini Molecular Cloud
• Source clustering in the Hi-GAL survey determined using a minimum spanning tree method
• Interplay between Young Stars and Molecular Clouds in the Ophiuchus Star-forming Complex
• The Effect of Magnetic Fields and Ambipolar Diffusion on Core Mass Functions
• The Role of Discs in the Collapse and Fragmentation of Prestellar Cores
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