LIGO/Virgo G298048: ALMA observations

We have used the Atacama Large Millimeter/submillimeter Array, ALMA, to observe the field of LIGO/Virgo candidate G298048 (The LIGO Scientific Collaboration and the Virgo Collaboration GCN Circ. 21509) and GRB 170817A (Connaughton et al. GCN Circ. 21506; Svinkin et al. GCN Circ. 21515), centered on the position of the optical transient reported in Coulter et al. (GCN Circ. 21529). Observations were taken at four epochs: 2017-08-18, 2017-08-20, 2017-08-21 and 2017-08-25 and have been carried out in the B7 band centred at 338.5 GHz (central wavelength 0.89 mm). The field of view covered an area of 18.3 arcsec. Data processing is underway. We thank ALMA for their excellent support.