TITLE:   GCN CIRCULAR
NUMBER:  37618
SUBJECT: EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
DATE:    24/09/27 20:49:52 GMT
FROM:    Weikang Zheng at UC Berkeley <weikang@berkeley.edu>

WeiKang Zheng (UCB), Jing Wang, Xuhui Han, Pinpin Zhang (NAOC),

Ryan Chornock, Natalie LeBaron, Erica Hammerstein, Thomas G. Brink

and Alexei V. Filippenko (UCB) report on behalf of the KAIT GRB team:


We observed the star 2MASS J18351416+2435115, which was within the

EP-FXT error circle from EP-WXT trigger (ID 01709059262; Liu et al.,

GCN 37593, 37594), with the Kast spectrograph on the 3 m Shane

telescope at Lick Observatory. Observations was performed about

0.793 days after the trigger, covering the 3500-10,000 A wavelength

range, with an exposure time of 900s. The spectrum shows a red

continuum flux overlapped with strong Balmer emission lines as well

as Ca II H&K and TiO emission lines, consistent with a typical dMe star

spectrum.


Additional B, V, R, and I-band photometry was obtained with the 0.76 m

Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory,

0.71 and 1.71 days after trigger. We measure B = 16.0, V = 14.4, R = 13.3,

and I = 11.7 mag. No variability was found within 0.1 mag accuracy between

the two epochs.


Since no photometric variability was found and based on one spectrum

alone, we cannot accept nor reject the possibility that this star

is associated with the EP trigger.


We thank the Lick Observatory staff, especially Elinor Gates and Paul

Canton for supporting the ToO observation at the Shane telescope.