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ObsMode is a yearly process which aims at preparing capabilities for future ALMA Observing cycles. The process has been running for a number of years tied to each ALMA observing cycle, with various leaderships. This document specifically summarizes the ObsMode2020 process (April- October 2020) with a new scheme led by the Joint ALMA Observatory. In the ObsMode2020 process, seven capabilities are identified as high priority items, for which it was originally aimed to be ready for Cycle 9. However, because of the observatory shutdown due to the covid-19 pandemic, we were forced to delay the test plan by one year. While no new data sets were obtained during the observatory shutdown, verifications using the existing data allowed us to offer the 7m-array polarization capability (in ACA standalone mode, single field) for Cycle 8 starting from October, 2021. In addition, subsystem readiness and policy-side preparations for the phased array observing mode were improved for Cycle 8. Other high priority items were decided to be carried over to the ObsMode2021 process., Comment: ALMA Memo Series #618. http://library.nrao.edu/public/memos/alma/main/memo618.pdf

$��$ Centauri A is the closest solar-type star to the Sun and offers the best opportunity to find and ultimately to characterize an Earth-sized planet located in its Habitable Zone (HZ). Here we describe initial results from an ALMA program to search for planets in the $��$ Cen AB system using differential astrometry at millimeter wavelengths. Our initial results include new absolute astrometric measurements of the proper motion, orbital motion, and parallax of the $��$ Cen system. These lead to an improved knowledge of the physical properties of both $��$ Cen A and B. Our estimates of ALMA's relative astrometric precision suggest that we will ultimately be sensitive to planets of a few 10s of Earth mass in orbits from 1-3 AU, where stable orbits are thought to exist., 24 pages, 11 figures. Accepted for publication in the Astronomical Journal. Full versions of Tables 6, 7 and 12 available in the source material