The successful launch of Astronomical Roentgen Telescope – X-ray Concentrator (ART-XC) instrument on board the Spectrum-Roentgen-Gamma (SRG) mission occurred at 15:30:57 13 July 2019 Moscow time.
See the recorded news conference (in Russian) and launch that begins at about T -01:00:00 (you can skip to the launch on the YouTube video), provided by the Russian Space Agency, or view on Roscosmos television feed.
Here are popular-level news articles in Nature and in Science
And here are some earlier youtube videos on the final assembly at Baikonur including arrival and integration followed by transport to the launch platform and verticality. Here is another version from Roscosmos of the rollout to the launch pad. Enjoy.