Extension of HOPS Out to 500 ParSecs (eHOPS). I. Identification and Modeling of Protostars in the Aquila Molecular Clouds

Abstract

We present a Spitzer/Herschel focused survey of the Aquila molecular clouds ($d\sim 436$~pc) as part of the eHOPS (extension of HOPS Out to 500 ParSecs) census of nearby protostars. For every source detected in the Herschel/PACS bands, the eHOPS-Aquila catalog contains 1-850~$\mu$m SEDs assembled from 2MASS, Spitzer, Herschel, WISE, and JCMT/SCUBA-2 data. Using a newly developed set of criteria, we classify objects by their SEDs as protostars, pre-ms sequence stars with disks, and galaxies. A total of 172 protostars are found in Aquila, tightly concentrated in the molecular filaments that thread the clouds. Of these, 71 (42\%) are Class 0 protostars, 54 (31\%) are Class I protostars, 43 (25\%) are flat-spectrum protostars, and 4 (2\%) are Class II sources. Ten of the Class 0 protostars are young PACS Bright Red Sources similar to those discovered in Orion. We compare the SEDs to a grid of radiative transfer models to constrain the luminosities, envelope densities, and envelope masses of the protostars. A comparison of the eHOPS-Aquila to the HOPS protostars in Orion finds that the protostellar luminosity functions in the two star-forming regions are statistically indistinguishable, the bolometric temperatures/envelope masses of eHOPS-Aquila protostars are shifted to cooler temperatures/higher masses, and the eHOPS-Aquila protostars do not show the decline in luminosity with evolution found in Orion. We briefly discuss whether these differences are due to biases between the samples, diverging star formation histories, or the influence of environment on protostellar evolution.

Accepted in ApJS. NASA IPAC/IRSA Data Release DOI: 10.26131/IRSA553

References in corpus (29)

• Array Programming with NumPy
• The NumPy array: a structure for efficient numerical computation
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• A Spitzer Survey of Young Stellar Clusters within One Kiloparsec of the Sun: Cluster Core Extraction and Basic Structural Analysis
• MAMBO Mapping of Spitzer c2d Small Clouds and Cores
• Spitzer Observations of NGC 1333: A Study of Structure and Evolution in a Nearby Embedded Cluster
• The c2d Spitzer spectroscopic survey of ices around low-mass young stellar objects II: CO2
• The Spitzer Gould Belt Survey of Large Nearby Interstellar Clouds: Discovery of a Dense Embedded Cluster in the Serpens-Aquila Rift
• A 24 Micron Point Source Catalog of the Galactic Plane from Spitzer/MIPSGAL
• The Gould's Belt Distances Survey (GOBELINS) III. The distance to the Serpens/Aquila Molecular Complex
• A Combined Spitzer and Chandra Survey of Young Stellar Objects in the Serpens Cloud Core
• Evolution of column density distributions within Orion~A
• A modular set of synthetic spectral energy distributions for young stellar objects
• The Nature of Transition Circumstellar Disks II. Southern Molecular Clouds
• Star-Gas Surface Density Correlations in Twelve Nearby Molecular Clouds I: Data Collection and Star-Sampled Analysis
• The Single-Cloud Star Formation Relation
• Characterizing the Youngest Herschel-detected Protostars I. Envelope Structure Revealed by CARMA Dust Continuum Observations
• The Evolution of Protostellar Outflow Cavities, Kinematics, and Angular Distribution of Momentum and Energy in Orion A: Evidence for Dynamical Cores
• An HST Survey of Protostellar Outflow Cavities: Does Feedback Clear Envelopes?
• The census of dense cores in the Serpens region from the Herschel Gould Belt Survey
• Spitzer/MIPS Imaging of NGC 650: Probing the History of Mass Loss on the Asymptotic Giant Branch
• 300: An ACA 870 $\mu$m Continuum Survey of Orion Protostars and their Evolution
• Characterizing the Youngest Herschel-detected Protostars II. Molecular Outflows from the Millimeter and the Far-infrared
• Low Mass Stars as Tracers of Star and Cluster Formation
• Detection of Irregular, Sub-mm Opaque Structures in the Orion Molecular Clouds: Protostars within 10000 years of formation?
• Protostellar and Protoplanetary Disk Masses in the Serpens Region
• The Herschel Orion Protostar Survey: Far-Infrared Photometry and Colors of Protostars and Their Variations across Orion A and B
• Deep Near-Infrared Survey Toward the W40 and Serpens South Region in Aquila Rift: A Comprehensive Catalog of Young Stellar Objects

Cited by in corpus (7)

• CAMPOS II. The onset of protostellar disk substructures and planet formation
• Hidden under a warm blanket: If planets existed in protostellar disks, they would hardly produce observable substructures
• Assessing the accuracy of the star formation rate measurements by direct star count in molecular clouds
• FAUST. XXVIII. High-Resolution ALMA Observations of Class 0/I Disks: Structure, Optical Depths, and Temperatures
• The accretion luminosity of Class I protostars
• A framework for modeling the evolution of young stellar objects
• Unlocking accretion rate diagnostics for high-mass protostars using JWST/MIRI HI lines