GCN Circular 9634

K. Aoki, M. Ishii (Subaru Telescope), M. Kuzuhara (Univ. of Tokyo), 
Y. Takahashi (Univ. of Advanced Study) and N. Kawai (Tokyo Tech) 
report on behalf of the Subaru GRB team:

We observed the field of GRB 090709A (Morris et al. GCN 9625
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with MOIRCS on Subaru Telescope in J and K bands under a
cirrus condition, starting at ~9:30 UT on July 9, approximately
2 hours after the burst.
We detected following two objects near the XRT error circle.
Their preliminary magnitudes based on a nearby 2MASS star are following.

object A:  J(Vega)=19.0, K(Vega)=18.2
object B:  J undetected, K(Vega)=18.6

We placed the K band finding chart at

http://www.hp.phys.titech.ac.jp/nkawai/grb/090709/GRB090709.jpg

We further performed spectroscopy for them with the following results:

Object A: zJH spectroscopy, a flat spectrum with no break detected.

Object B: HK and zJH spectroscopy, a continuum detected in K-band,
   no continuum detected in J band, 
   possibly no continuum in H-band but with high background.

Lack of H band continuum could suggest that the object B is at high 
redshift (z~10), though its poor SNR does not allow us to confirm it.
Fading is not confirmed for either of them.

Further NIR/optical observations are strongly encouraged.