ion of around 50 IMBHs in the inner 10 pc of the Milky Way. However, these are expected to have masses of the order of $10^3 M_{\odot}$, since they should be born in lower mass ($\approx 10^5 M_{\odot}$) star clusters, forming closer to the Galactic Center, such as the Arches [@Nagata95; @Cotera96; @Serabyn98] and the Quintuplet [@Nagata90; @Figer95]. Finally, @Fragione18 modeled the fate of IMBHs born in globular clusters in the halo of Milky-Way-like galaxies and found that the most massive ($\gtrsim 10^6 M_{\odot}$) globular clusters might have delivered few massive ($\gtrsim 10^4 M_{\odot}$) IMBHs at distances smaller than 100 pc from the centre of the galaxy. In contrast with the assumptions of @Mastrobuono14, @McMillan03 and @Fragione18 expect the parent globular cluster to have dissolved before reaching the observed position of CO-0.40-0.22\* and have left a “naked” black hole. From the IR observations of CO-0.40-0.22 [@Ravi18], it is almost impossible to understand whether the IMBH candidate is naked or surrounded by a star cluster, because of the high absorption along the line of sight.

These arguments show that it is very unlikely that such a massive IMBH formed on the spot: Arches/Quintuplet-like star clusters would not be massive enough to produce IMBHs with mass $>10^4 M_{\odot}$. A more massive local parent cluster, instead, should have been dragged, along with its IMBH, to much smaller distances from SgrA\*. Thus, the most plausible scenario is that this object might have formed in the halo of our Galaxy and was successively brought at its current position by its original host, which dissolved on the way.

Hence, assuming that CO-0.40-0.22\* is an IMBH with high mass, as those resulting from our calculation, is not in tension with current theoretical estimates.

As already mentioned, different explanations for the high velocity gradient of CO-0.40-0.22 are possible. A supernova explosion inside the cloud would provide enough energy to generate it [@Tanaka14; @Yalinewich17] and it is a feasible