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GCN Circular 21610

LIGO/VIRGO G298048: SALT optical spectra of the candidate optical/NIR counterpart of the gravitational wave G298048 in NGC4993.
2017-08-20T06:14:37Z (6 years ago)
Stephen Potter at SAAO <>
M. Shara (AMNH), T. Williams (SAAO), P. Vaisanen (SAAO/SALT), S. Potter
(SAAO), E. Romero Colmenero (SAAO/SALT), S. Crawford (SAAO), D. Buckley
(SAAO), J Cooke (Swinburne), Igor Andreoni (Swinburne), Tyler Pritchard
(Swinburne), Jirong Mao (YNAO)

Spectra of an unresolved source at coordinates RA=197.4504, DEC=-23.3815
near the galaxy NGC 4993, obtained with the Robert Stobie Spectrograph on
the Southern African Large Telescope at UT 17:07:19.703 on 18 August 2017
and at UT 16:58:32.764 on 19 August 2017 during early twilight.   The
spectra extends between 3600-8000 Angstroms with a resolution of ~300.  The
spectra is heavily blended with the host galaxy.  After subtraction of the
host galaxy spectra from the 18 August, the source shows a spectra
increasing in flux from 8000 A to 5000 A, which then decreases in flux
after 4500 A.   The spectra from the 19 August 2017 was taken early
twilight and too noisy to say anything definitive.
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