[vsnet-grb-info 23426] LIGO/Virgo S190814bv: Swift UVOT - no new counterpart candidates identified

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25525
SUBJECT: LIGO/Virgo S190814bv: Swift UVOT - no new counterpart candidates identified
DATE:    19/08/28 18:31:22 GMT
FROM:    Alice Breeveld at MSSL-UCL  <a.breeveld at ucl.ac.uk>

A. A. Breeveld (UCL-MSSL), S. R. Oates (U. Warwick), F. E. Marshall (NASA/GSFC), N. P. M. Kuin 
(UCL-MSSL),  M.J. Page (UCL-MSSL), P. Brown (TAMU), C. Gronwall (PSU), M. de Pasquale (Istambul U.), 
M. H. Siegel (PSU), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB), S. D. Barthelmy (NASA/GSFC), A. 
P. Beardmore (U. Leicester), D. N. Burrows (PSU), S. Campana (INAF-OAB), S. B. Cenko (NASA/GSFC), G. 
Cusumano (INAF-IASF PA), V. D'Elia(ASDC), P. A. Evans (U. Leicester), P. Giommi (ASI), D. Hartmann 
(Clemson U.), J. A. Kennea (PSU), H. A. Krimm (NSF), A. Y. Lien (GSFC/UMBC), D. B. Malesani 
(DARK/NBI), A. Melandri (INAF-OAB), J. A. Nousek (PSU), P. T. O'Brien (U. Leicester), J. P. Osborne 
(U. Leicester), C. Pagani (U. Leicester), K. L. Page (U.Leicester), D.M. Palmer (LANL), M. Perri 
(ASDC), J. L. Racusin (NASA/GSFC), T. Sakamoto (AGU), B. Sbarufatti (INAF-OAB/PSU), G. Tagliaferri 
(INAF-OAB), A. Tohuvavohu (PSU), and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift team:

The Swift UVOT instrument started follow up observations of the LIGO-Virgo event S190814bv (LVC GCN 
Circ. 25324) 11ks after the trigger following the tiling programme described in Evans et al. (GNC 
Circ. 25400).

The UVOT approach for searching for the ultraviolet-optical counterpart has been described in Kuin 
et al. (GCN Circ. 24767). The limiting magnitude can vary but typically is 18.6th magnitude (Vega) 
in the U filter. In the 352 fields that were observed, UVOT detected 98 counterpart candidates and 
2257 catalogued galaxies. None of the candidates from the automated processing proved to be a viable 
candidates. Neither did the additional inspection of all 2257 imaged galaxies lead to a candidate 
missed by the automated processing.