Journal ArticleObservations of comet C/2020 F3 (NEOWISE) with IRAM telescopesBiver, N.; Boissier, J.; Bockelée-Morvan, D.; Crovisier, J.; Cottin, H.; Cordiner, M. A.; Roth, N. X.; Moreno, R.We present the results of millimetre-wave spectroscopic and continuum observations of the comet C/2020 F3 (NEOWISE) undertaken with the Institut de RadioAstronomie Millimétrique (IRAM) 30-m and the NOrthern Extended Millimeter Array (NOEMA) telescopes on 22, 25–27 July, and 7 August 2020. Production rates of HCN, HNC, CH 3 OH CS, H 2 CO, CH 3 CN, H 2 S, and CO were determined with upper limits on six other species. The comet shows abundances within the range observed for other comets. The CO abundance is low (3.2% relative to water), while H 2 S is relatively abundant (1.1% relative to water). The H 2 CO abundance shows a steep variation with heliocentric distance, possibly related to a distributed production from the dust or macro-molecular source. The CH 3 OH and H 2 S production rates show a slower decrease post-perihelion than water. There was no detection of the nucleus point source contribution based on the interferometric map of the continuum (implying a size of r < 4.7 km), but this yielded an estimate of the dust production rate, leading to a relatively low dust-to-gas ratio of 0.7 ± 0.3 on 22.4 July 2020.2022-12-0110450612Astronomy & Astrophysics668A1710004-6361https://doi.org/10.1051/0004-6361/2022449702009253National Science Foundation