OMAyA - a 1mm wavelength focal-plane array receiver for the Large Millimeter Telescope

University Of Massachusetts Amherst, Amherst MA

Investigators

Abstract

New stars are formed in enormous regions of cold gas and dust called giant molecular clouds. The properties of such regions can be studied using radio spectroscopic observations. These gas clouds contain many atomic species and simple molecules that produce spectral lines in this wavelength range. Spectroscopic observations not only reveal the physical and chemical properties of star-forming regions but can also measure the complex gas motions. This project will complete the construction of a sensitive multi-pixel receiver system called OMAyA (One Millimeter-wave Array for Astronomy), which will be installed and commissioned on the 50-meter diameter Large Millimeter Telescope (LMT) in Mexico. The additional advantage of a low atmospheric loss provided by the high mountain-top location will enable sensitive scientific observations of distant galaxies, clouds in our own galaxy and comet flybys in the solar system. The receiver will be available to all LMT observers, and 15% of the LMT observing time is freely accessible to any US–based astronomer. This project will complete the construction, installation, and commissioning of OMAyA, a powerful heterodyne focal-plane array receiver system that is designed to operate in the 210 – 280 GHz (~1mm wavelength) atmospheric window. OMAyA will have 8 pixels, each capable of simultaneously measuring 2 spectral lines in 2 polarizations, thus generating 32 distinct spectra with one pointing. Each pixel of OMAyA features a novel mixer block with a high level of integration and is equipped with the ability to detect two orthogonal polarizations, and contains sideband-separation super-conducting mixers. The design and construction of a significant portion of the OMAyA receiver has been completed. In this project, the receiver will be finished and installed on the LMT. As a purely technical advance, this project will implement a high level of integration of mixer, amplifier, local oscillator injection components in an innovative dual-polarized sideband separation system that will be used throughout the field of heterodyne focal-plane arrays. As a facility instrument on the LMT available for American and Mexican astronomers, OMAyA will enable exciting new scientific observing programs. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.