I did my thesis on X-ray observations of a large sample of supernova remnants using recent X-ray Space
Observatories of ASCA and ROSAT, and defined a group of supernova remnants with X-ray
center-filled, thermal emission and a radio shell as a new class of supernova remnants, termed
"Mixed-morphology supernova remnants", because they share unique X-ray and environmental
properties of ISM and they often are interacting with molecular clouds (Rho & Petre 1998). Using ISO we
found that these remnants are very bright in infrared light due to rapid cooling when interacting with
dense molecular clouds (Reach & Rho 1996, 1998). Currently I am working on these SNR using 2MASS
data; they are also bright in 2MASS bands due to shocked molecular hydrogen and [Fe II] lines as shown
in the case of IC 443 (Rho et al. 2000). Surprisingly, there are very limited number of SNRs observed in
near-infrared in the past, and thus 2MASS will reveal new near-infrared emitting supernova remnants,
which would often emit mid-, far- infrared emission. These remnants could have easily missed by IRAS
because of their small angular sizes or small area of infrared emitting regions (often thin filaments)
and/or lack of sensitivity. High resolution 2MASS images that cover each entire remnant and are
covering entire sky, are beautifully revealing infrared emission from supernova remnants (see 2MASS
web page for image gallery). Up to the date, we have detected more than 15 supernova remnants using
2MASS and plan to make a complete catalog available, eventually with mosaiced images in fits format.

1)   Near-infrared Imaging and [O I] Spectroscopy of IC 443 using 2MASS and ISO 
2)   RCW 103 :   2MASS Near-infrared images of RCW 103: a young SNR in a dense medium
3)  Cas A : work in progress