GCN Circular 21684
Subject
LIGO/Virgo G298048: Near-infrared fading from Gemini-South
Event
Date
2017-08-25T04:04:17Z (9 years ago)
From
Ryan Chornock at Ohio U <chornock@ohio.edu>
R. Chornock (Ohio University) and E. Berger (Harvard) report on behalf of a
larger collaboration:
Further to our previous report (LVC GCN 21638), we have continued near-infrared
observations of the optical counterpart (Coulter et al., LVC GCN 21529; Allam et
al., LVC GCN 21530; Yang et al., LVC GCN 21531) to the LIGO/Virgo source G298048
(GCNs 21509, 21513) using FLAMINGOS2 on Gemini-South (PI: Chornock).
Over the course of our initial observations, obtained during the first 4.5 days
after the GW trigger, the H-band flux from the near-infrared source was not
strongly variable. However, in H-band acquisition images obtained tonight
(20170824 at 23:47 UT, t~7.5 d after the GW trigger), the NIR counterpart
appears substantially fainter (by >1 magnitude) compared to our previous
observations three nights earlier. A phase of more rapid NIR fading may have begun.
We thank the entire Gemini-South staff, but particularly H. Kim, G. Diaz, J.
Chavez, P. Candia, and the director, Laura Ferrarese, for their support of these
observations.