  AX J1843.8-0352 is a new X-ray SNR identified to the radio complex G28.6-0.1
with the ASCA satellite. Chandra discovered two distinct components from this
SNR: non-thermal and thin thermal X-ray emissions. The non-thermal component is
fitted with a power-law spectrum of photon index 2.0. The morphology is
complicated, but roughly an elliptical shape with a mean diameter of about
7'-10'. The east to south rims of the ellipse are associated with the
non-thermal radio sources C, F and G (Helfand et al. 1989). The power-law slope
of the radio spectrum can be smoothly connected to that of X-rays with a break
at around the optical-IR band, hence would be due to synchrotron X-rays
accelerated probably to > 1 TeV at the shell of the SNR. The thermal component
near the southeast rim is a thin plasma of about 0.8 keV temperature. It has
the appearance of a "Tadpole" figure with a head of 30"x 40"-size and a tail of
30"-long. Although this emission is associated with the west part of the radio
source F, the absorption is about two times larger than that of the non-thermal
X-rays, the bulk of the SNR emission. Therefore, together with the peculiar
morphology, whether the thermal plasma is a part of the SNR or a background
object is unclear.
