urn:nasa:pds:context:telescope:eso-chajnantor.alma 1.0 1.15.0.0 Product_Context 2022-02-24 1.0 Initial export from OLAF urn:nasa:pds:context:instrument:eso-chajnantor.alma.alma_radio_receiver telescope_to_instrument urn:nasa:pds:context:facility:observatory.eso-chajnantor telescope_to_facility 12 292.24667 -23.01917 5059 Unknown The Atacama Large Millimeter/submillimeter Array, or ALMA, is an international collaboration to operate a telescope of revolutionary design from a site in the foothills of Chile's Andes Mountains. ALMA is composed of 66 high precision antennae, operating at wavelengths of 0.32 to 3.6 mm. Its main 12-meter array has fifty antennae, each measuring 12 meters in diameter, acting together as a single telescope — an interferometer. An additional compact array of four 12-meter and twelve 7-meter antennas complements this. The ALMA antennae can be arranged in different configurations, where the maximum distance between antennae can vary from 150 meters to 16 kilometers. The ALMA correlator, a specialized computer that combines the information received by the antennae, can perform a remarkable 16000 million-million (1.6x1016) operations per second. ALMA was inaugurated in 2013, but early scientific observations using a partial array already began in 2011. ALMA is a partnership between ESO (representing its Member States), NSF (USA) and NINS (Japan), together with NRC (Canada), NSC and ASIAA (Taiwan), and KASI (South Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. Each radio receiver type is sensitive to a particular wavelength range (band), and data can only be taken in one band at a time. To date, eight out of a planned ten receivers have been installed on each ALMA antenna. These bands range from band 3, starting at wavelengths of 3.6 mm, to band 10, ending at 0.3 mm. Band 1 is under construction (covering wavelengths between 6 and 8.5 millimeters), and band 2 (covering 3.3 to 4.5 millimeters) might be added in the future. Band 3: Produced by the Herzberg Institute of Astrophysics in Canada. It covers the longest wavelength range of the bands initially installed, between 2.6-3.6 mm (84-116 GHz). Band 4: Developed by National Astronomical Observatory of Japan (NAOJ). It covers a wavelength range of 1.8-2.4 mm (125-163 GHz). Band 5: Developed by the Group for Advanced Receiver Development (GARD) at Onsala Space Observatory, Chalmers University of Technology, Sweden. The production of the 66 receivers for the ALMA observatory was done jointly by GARD and NOVA. It covers a wavelength range of 1.4-1.8 mm (163-211 GHz). Band 6: Produced by the National Radio Astronomy Observatory (NRAO). It covers the wavelength range of 1.1-1.4 mm (211-275 GHz). Band 7: Delivered by the Institut de Radio Astronomie Millimétrique (IRAM). It covers the wavelength range of 0.8-1.1 mm (275-373 GHz). Band 8: Developed by NAOJ. It covers the wavelength range of 0.6-0.8 mm (385-800 GHz). Band 9: Produced by the Nederlandse Onderzoekschool voor Astronomie (NOVA). It covers the wavelength range 0.4-0.5 mm (602-720 GHz). Band 10: Developed and produced led by NAOJ. It covers the wavelength range 0.3-0.4 mm (787-950 GHz).