AGB interlopers in YSO catalogues hunted out by NEOWISE

Abstract

AGBs and YSOs often share the same domains in IR color-magnitude or color-color diagrams leading to potential mis-classification. We extracted a list of AGB interlopers from the published YSO catalogues using the periodogram analysis on NEOWISE time series data. YSO IR variability is typically stochastic and linked to episodic mass accretion. Furthermore, most variable YSOs are at an early evolutionary stage, with significant surrounding envelope and/or disk material. In contrast, AGBs are often identified by a well defined sinusoidal variability with periods of a few hundreds days. From our periodogram analysis of all known low mass YSOs in the Gould Belt, we find 85 AGB candidates, out of which 62 were previously classified as late-stage Class III YSOs. Most of these new AGB candidates have similar IR colors to O-rich AGBs. We observed 73 of these AGB candidates in the H2O, CH3OH and SiO maser lines to further reveal their nature. The SiO maser emission was detected in 10 sources, confirming them as AGBs since low mass YSOs, especially Class III YSOs, do not show such maser emission. The H2O and CH3OH maser lines were detected in none of our targets.

arXiv commentAccepted for publication in ApJL

References in corpus (28)

• Gaia Data Release 2. Summary of the contents and survey properties
• VISTA Variables in the Via Lactea (VVV): The public ESO near-IR variability survey of the Milky Way
• The Spitzer Space Telescope Survey of the Orion A & B Molecular Clouds - Part I: A Census of Dusty Young Stellar Objects and a Study of their Mid-IR Variability
• CSI 2264: Simultaneous optical and infrared light curves of young disk-bearing stars in NGC 2264 with CoRoT and Spitzer-- evidence for multiple origins of variability
• Young Stellar Objects in the Gould Belt
• A Classification Scheme for Young Stellar Objects Using the WIDE-FIELD INFRARED SURVEY EXPLORER AllWISE Catalog: Revealing Low-Density Star Formation in the Outer Galaxy
• Numerical simulations of stellar SiO maser variability. Investigation of the effect of shocks
• A Survey for New Members of Taurus from Stellar to Planetary Masses
• Single dish performance of KVN 21-m radio telescopes:Simultaneous observations at 22 and 43 GHz
• Online Database of Class I Methanol Masers
• SiO Maser Survey of IRAS Sources in the Inner Galactic Disk
• An initial overview of the extent and structure of recent star formation within the Serpens Molecular Cloud using Gaia Data Release 2
• Pulsed Accretion in a Variable Protostar
• Eruptive Variable Stars and Outflows in Serpens NW
• The JCMT Transient Survey: Detection of sub-mm variability in a Class I protostar EC 53 in Serpens Main
• The Relationship between Mid-Infrared and Sub-Millimetre Variability of Deeply Embedded Protostars
• Pulsation Modes of Long-Period Variables in the Period-Luminosity Plane
• Young Faithful: The Eruptions of EC 53 as It Cycles through Filling and Draining the Inner Disk
• Pulsed Accretion in the T Tauri Binary TWA 3A
• OH-selected AGB and post-AGB stellar objects II.Blue versus red evolution off the AGB
• Infrared two-colour diagrams for AGB stars using AKARI, MSX, IRAS and NIR data
• Characterising the i-band variability of YSOs over six orders of magnitude in timescale
• Gaia DR2 view of the Lupus V-VI clouds: the candidate diskless young stellar objects are mainly background contaminants
• SiO Maser Survey off the Galactic Plane: A Signature of Streaming Motion
• Carbon- and Oxygen-rich Asymptotic Giant Branch (AGB) stars in the Bulge Asymmetries and Dynamical Evolution (BAaDE) survey
• Characterizing AGB stars in Wide-field Infrared Survey Explorer (WISE) bands
• Classification Study of WISE Infrared Sources: Identification of Candidate Asymptotic Giant Branch Stars
• First detection of 22 GHz H2O masers in TX Camelopardalis

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• Quantifying Variability of YSOs in the Mid-IR Over Six Years with NEOWISE
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• A Naive Bayes Classifier for identifying Class II YSOs
• Distributed YSOs in the Perseus Molecular Cloud from the Gaia and LAMOST Surveys
• The JCMT Transient Survey: Single Epoch Transients and Variability of Faint Sources
• The SPHEREx Target List of Ice Sources (SPLICES)
• The Ages of Optically Bright Sub-Clusters in the Serpens Star-Forming Region
• Probabilistic Classification of Infrared-selected targets for SPHEREx mission: In search of YSOs