Astronomical Research and Technical Support of Millimeter-Wavelength VLBI

Northeast Radio Observatory Corp, Westford MA

Investigators

Abstract

AST-0096454. Northeast Radio Observatory Corporation. PI: A. A. E. Rogers Astronomical Research and Technical Support of Millimeter Wavelength VLBI This award supports the operation of the Northeast Radio Observatory's "Coordinated mm-VLBI Array" (CMVA). The CMVA provides unified scheduling, support, and analysis infrastructure for an ad hoc network of observatories which carry out very long baseline interferometry (VLBI) at millimeter wavelengths. The CMVA network consists of a core group of mm-wave observatories which have agreed to make approximately two weeks per year available for VLBI; additional facilities make time available on a per-proposal basis. The CMVA is unique, and its intent is to make mm-wave VLBI available to all astronomers, not just those who are experts in the technique. Millimeter-wavelength VLBI achieves the highest angular resolution in astronomy-typically 50 milliarcseconds at 3mm. Only such resolutions can begin to reveal the compact astrophysical structures associated with the massive central engines of active galactic nuclei such as quasars and BL Lacertids, and only at millimeter wavelengths does one minimize the inherent limitations of continuum VLBI due to scattering by the interstellar plasma and optical depth effects. The millimeter band is also rich in molecular masers whose structure can only be resolved by VLBI. During the past award period 60 investigators from more than 25 institutions made use of the CMVA, producing observations of the Galactic Center, a survey of active galactic nuclei, and studies of methanol and silicon monoxide masers in both star-forming regions and the envelopes of evolved stars. This proposal requests funds to continue operation of the CMVA for a final 3-year period. At that time, the proposers expect that 3mm VLBI efforts will fully pass to the NRAO's VLBA - which will have completed upgrading to 3mm capability - and the CMVA's ad hoc activities will be abandoned. ***