The VLA Orion A Large Survey
(VOLS)
VOLS is a VLA Large Project approved in 22A semester.
The early stages of star and planet formation involve a balance between accretion and ejection of material during the gravitational collapse. This balance and the consequent protostellar evolution are crucial in determining the final properties of stars and their planetary systems.
The VOLS large project will observe the northern region of the Orion A molecular cloud, the nearest star-forming complex containing a broad range of environments populated by protostars and YSOs with different masses and evolutionary stages, representing a testbed for star formation theories.
VOLS aims to establish a paradigm in our understanding of the nature of the radio emission from YSOs by building a census of the stellar population down to scales of 120 au. The ultimate goal of the VOLS project is to understand the evolution of the mass-accretion and mass-loss rates across the mass spectrum and birth environment.
VOLS will constitute the deepest survey of Orion A at centimeter wavelengths over an area of 0.5 deg2 (see Figure below for the survey coverage). It will also provide to the community with a legacy database that will be crucial for the next generation of radio interferometers.
Image from Grosschedl et al. (2019)
Project Summary
Orion A is the nearest star-forming complex containing a broad range of environments populated by protostars and YSOs with different masses and evolutionary stages, representing a testbed for star formation theories. The Large Program VOLS aims to establish a paradigm in our understanding of the nature of the radio emission from YSOs by bulding a census, at two frequency bands, of the YSOs down to scales of 120 au. The ultimate goal of the project is to understand the evolution of mass-accretion and mass-loss rates across the mass spectrum and birth environment. This will be the first radio survey to cover a large area of Orion A at subarcsecond resolution, improving the sensitivity by a factor of 20 compared to previous large-scale surveys in Orion. Together with previous ancillary datasets across the EM spectrum, VOLS will provide the ultimate correlation between the characteristics of the radio emission from YSOs and their stellar properties. VOLS publicly accessible images and catalogs will be of exceptional legacy value from the JVLA to the general community for science goals that go beyond Orion, the archetypal region of the present proposal, and to prepare follow-up projects toward more distant regions with the next generation radio facilities.
