High-Angular-Resolution and High-Sensitivity Science Enabled by Beamformed ALMA

TL;DR

The paper discusses the development of a beamformer for ALMA that will significantly enhance VLBI observations, enabling high-resolution, high-sensitivity studies across various astrophysical phenomena.

Contribution

Introduction of a new beamformer for ALMA that aggregates its entire array for unprecedented sensitivity and resolution in VLBI observations.

Findings

Enhanced angular resolution in Bands 6 and 7 (1.3 and 0.8 mm)

Improved sensitivity for VLBI in Bands 1 and 3 (7 and 3 mm)

Potential for groundbreaking scientific discoveries in black hole physics, galaxy evolution, and fundamental constants.

Abstract

An international consortium is presently constructing a beamformer for the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile that will be available as a facility instrument. The beamformer will aggregate the entire collecting area of the array into a single, very large aperture. The extraordinary sensitivity of phased ALMA, combined with the extremely fine angular resolution available on baselines to the Northern Hemisphere, will enable transformational new very long baseline interferometry (VLBI) observations in Bands 6 and 7 (1.3 and 0.8 mm) and provide substantial improvements to existing VLBI arrays in Bands 1 and 3 (7 and 3 mm). The ALMA beamformer will have impact on a variety of scientific topics, including accretion and outflow processes around black holes in active galactic nuclei (AGN), tests of general relativity near black holes, jet launch and collimation from AGN and microquasars, pulsar and magnetar emission processes, the chemical history of the universe and the evolution of fundamental constants across cosmic time, maser science, and astrometry.