FAUST IX. Multi-band, multi-scale dust study of L1527 IRS. Evidence for dust properties variations within the envelope of a Class 0/I YSO

Abstract

Early dust grain growth in protostellar envelopes infalling on young discs has been suggested in recent studies, supporting the hypothesis that dust particles start to agglomerate already during the Class 0/I phase of young stellar objects (YSOs). If this early evolution were confirmed, it would impact the usually assumed initial conditions of planet formation, where only particles with sizes $\lesssim 0.25\mu$m are usually considered for protostellar envelopes. We aim to determine the maximum grain size of the dust population in the envelope of the Class 0/I protostar L1527 IRS, located in the Taurus star-forming region (140 pc). We use Atacama Large millimetre/sub-millimetre Array (ALMA) and Atacama Compact Array (ACA) archival data and present new observations, in an effort to both enhance the signal-to-noise ratio of the faint extended continuum emission and properly account for the compact emission from the inner disc. Using observations performed in four wavelength bands and extending the spatial range of previous studies, we aim to place tight constraints on the spectral ($\alpha$) and dust emissivity ($\beta$) indices in the envelope of L1527 IRS. We find a rather flat $\alpha \sim$ 3.0 profile in the range 50-2000 au. Accounting for the envelope temperature profile, we derive values for the dust emissivity index, 0.9 < $\beta$ < 1.6, and reveal a tentative, positive outward gradient. This could be interpreted as a distribution of mainly ISM-like grains at 2000 au, gradually progressing to (sub-)millimetre-sized dust grains in the inner envelope, where at R=300 au, $\beta$ = 1.1 +/- 0.1. Our study supports a variation of the dust properties in the envelope of L1527 IRS. We discuss how this can be the result of in-situ grain growth, dust differential collapse from the parent core, or upward transport of disc large grains.

Accepted for publication in A&A. Contains 18 pages, 21 figures, 5 tables Replacement on Nov 22 to change title number of FAUST series from "X" to "IX."

References in corpus (27)

• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• Coagulation, fragmentation and radial motion of solid particles in protoplanetary disks
• A Large Catalog of Accurate Distances to Local Molecular Clouds: The Gaia DR2 Edition
• Dust masses of young disks: constraining the initial solid reservoir for planet formation
• Formation of a Keplerian disk in the infalling envelope around L1527 IRS: transformation from infalling motions to Kepler motions
• Four annular structures in a protostellar disk less than 500,000 years old
• Grain growth in the envelopes and disks of Class I protostars
• The Ophiuchus DIsk Survey Employing ALMA (ODISEA): Disk Dust Mass Distributions across Protostellar Evolutionary Classes
• Low dust emissivities and radial variations in the envelopes of Class 0 protostars: a signature of early grain growth?
• Constraining the Envelope Structure of L1527 IRS: Infrared Scattered Light Modeling
• The CALYPSO IRAM-PdBI survey of jets from Class 0 protostars. Are jets ubiquitous in young stars ?
• The protoplanetary disk population in the rho-Ophiuchi region L1688 and the time evolution of Class II YSOs
• Multi-wavelength continuum sizes of protoplanetary discs: scaling relations and implications for grain growth and radial drift
• ALMA Observations of the Protostar L1527 IRS: Probing Details of the Disk and the Envelope Structures
• "Ash-fall" induced by molecular outflow in protostar evolution
• Protostellar collapse: the conditions to form dust rich protoplanetary disks
• Protostellar collapse simulations in spherical geometry with dust coagulation and fragmentation
• On the accuracy of the ALMA flux calibration in the time domain and across spectral windows
• Demographics of disks around young very low-mass stars and brown dwarfs in Lupus
• Substructure Formation in a Protostellar Disk of L1527 IRS
• Revealing the dust grain size in the inner envelope of the Class I protostar Per-emb-50
• Early planet formation in embedded protostellar disks: Setting the stage for the first generation of planetesimals
• Coreshine in L1506C - Evidence for a primitive big-grain component or indication for a turbulent core history?
• Formation of dust clumps with sub-Jupiter mass and cold shadowed region in gravitationally unstable disk around Class 0/I protostar in L1527 IRS
• Dust coagulation and fragmentation in a collapsing cloud core and their influence on non-ideal magnetohydrodynamic effects
• Dust grains cannot grow to millimeter sizes in protostellar envelopes
• Revisiting collisional dust growth in Class 0/I protostellar disks: Sweep-up can convert a few $10M_{\oplus }$ of dust into kg pebbles in 0.1 Myr

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