Herschel far-infrared photometric monitoring of protostars in the Orion Nebula Cluster

Abstract

We have obtained time series observations of the Orion Nebula Cluster at 70 microns and 160 microns from the Herschel/PACS Photometer. This represents the first wide-field far-infrared photometric monitoring of a young star forming region. The acquired 35'x35' maps show complex extended structures, with unprecedented details, that trace the interaction between the molecular gas and the young hot stars. We detect 43 protostars, most of which are situated along the integral-shaped filament extending from the Orion nebula, through OMC2 and to OMC3. We present high-reliability light curves for some of these objects using the first six epochs of our observing program spread over 6 weeks. We find amplitude variations in excess of 20% for a fraction of the detected protostars over periods as short as a few weeks. This is inconsistent with the dynamical time-scales of cool far-IR emitting material that orbits at hundreds of AU from the protostar, and it suggests that the mechanism(s) responsible for the observed variability originates from the inner region of the protostars, likely driven by variable mass accretion.

14 pages, 3 figures, 2 tables

References in corpus (5)

• Identifying the Low Luminosity Population of Embedded Protostars in the c2d Observations of Clouds and Cores
• Variability of Disk Emission in Pre-Main Sequence and Related Stars. I. HD 31648 and HD 163296 - Isolated Herbig Ae Stars Driving Herbig-Haro Flows
• The outburst of the eruptive young star OO Serpentis between 1995 and 2006
• Long-term infrared variability of the UX Ori-type star SV Cep
• The Herschel/PACS 2560 bolometers imaging camera

Cited by in corpus (27)

• 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
• The Herschel Orion Protostar Survey: Spectral Energy Distributions and Fits Using a Grid of Protostellar Models
• Variable protostellar accretion with episodic bursts
• Three-Dimensional Radiation Transfer in Young Stellar Objects
• Continuum Variability of Deeply Embedded Protostars as a Probe of Envelope Structure
• CCAT-prime Collaboration: Science Goals and Forecasts with Prime-Cam on the Fred Young Submillimeter Telescope
• Young Stellar Object Variability (YSOVAR): Long Timescale Variations in the Mid-Infrared
• HOPS 383: An Outbursting Class 0 Protostar in Orion
• Review: Far-Infrared Instrumentation and Technology Development for the Next Decade
• Molecule sublimation as a tracer of protostellar accretion: Evidence for accretion bursts from high angular resolution C18O images
• Chemical tracers of episodic accretion in low-mass protostars
• How do stars gain their mass? A JCMT/SCUBA-2 Transient Survey of Protostars in Nearby Star Forming Regions
• Zooming in on Individual Star Formation: Low- and High-mass Stars
• Constraining the Rate of Protostellar Accretion Outbursts in the Orion Molecular Clouds
• The JCMT Transient Survey: Stochastic and Secular Variability of Protostars and Disks In the Sub-Millimeter Observed Over Eighteen Months
• Near-Infrared Variability in the Orion Nebula Cluster
• Long-term variability of T Tauri stars using WASP
• Hints for Small Disks around Very Low-Mass Stars and Brown Dwarfs
• Anomalous CO2 Ice Toward HOPS-68: A Tracer of Protostellar Feedback
• The JCMT Transient Survey: An Extraordinary Submillimetre Flare in the T Tauri Binary System JW 566
• Brown dwarf disks with Herschel: Linking far-infrared and (sub)-mm fluxes
• The nature of very low luminosity objects (VeLLOs)
• CoRoT 223992193: Investigating the variability in a low-mass, pre-main sequence eclipsing binary with evidence of a circumbinary disk
• T Tauri stars in the SuperWASP and NSVS surveys
• The Role of Magnetic Fields in Transient Seismic Emission Driven by Atmospheric Heating in Flares
• Modeling Hadronic Gamma-ray Emissions from Solar Flares and Prospects for Detecting Non-thermal Signatures from Protostars
• The extraordinary far-infrared variation of a protostar: Herschel/PACS observations of LRLL54361