The source
The hot molecular core G31.41+0.31
G31.41+0.31 (hereafter G31) is a well known HMC located at 3.75 kpc, with a
luminosity > 104 L☉ (Beltran et al. 2005) that has no UC HII region embedded on it (Cesaroni et al.
2010). Interferometric studies at millimeter wavelengths with PdBI, SMA, and ALMA have revealed
that the core is very chemically rich (Beltran et al. 2005, 2009; Cesaroni et al. 2011, 2017; Rivilla
et al. 2017a), presenting prominent emission in a large number of COMs. In particular, the
first detection of glycolaldehyde outside the Galactic Center has been obtained towards G31 (Beltran
et al. 2009), and heavy complex molecules such as methyl formate or ethylene glycol have also been
observed (Rivilla et al. 2017a). Up to now, we have identified 45 molecular species in G31
(e.g. Rivilla et al. 2017a), including 16 COMs (two of them with 10 atoms), 23 isotopologues, 6
deuterated species, 2 cyclic molecules, 4 positive ions, and several H and He recombination lines.
This makes G31 one of the most chemically rich HMCs in the Galaxy, an excellent target to search
for even more complex species, and a template for future studies of chemistry in HMCs.
