  This paper presents a detailed analysis of supernova remnant (SNR) N103B
located in the Large Magellanic Cloud (LMC), based on Suzaku and Chandra
observations. The spectrum of the entire SNR was reproduced using 3 ISM
components with the kT of 0.32, 0.56, and 0.92keV and one ejecta component of
3.96keV, based on spectral analysis of the Suzaku/XIS data. The ejecta was
overabundant in heavy elements, such as Mg, Si, S, Ca, Fe, and Ni. The
unprecedentedly high quality of data obtained by XIS, allowed us to correctly
distinguish between the emissions from the ISM and the ejecta for the first
time. Combining XIS spectral analysis with Chandra/ACIS image analysis, we
verified that the ejecta distributions for elements from Si to Fe-K were
similar to one another, although Fe-K emission was located slightly inward
compared with that of lighter elements such as Si, S, Ar, and Ca. The
onion-like structure of the ejecta was maintained after the SN. In addition,
the ISM emission represented by O and Fe-L was located inside the ejecta
emission. We compared hydrogen-rich ejecta plasma, which is indicative of Type
II SNRs, with plasma rich in heavy elements and poor in hydrogen, which is
mainly observed in Type Ia. In the case of N103B, we could not determine
whether the origin of the continuum emission in the 4.0-6.0keV band was from
ejecta or high-temperature ISM only based on the spectral modeling of XIS data.
High-energy continuum images in the 5.2-6.0keV band obtained by ACIS were
extremely similar to those of ejecta, implying that the origin of the
high-energy continuum might indeed be the ejecta. By combining spectral
analysis with high-energy continuum images, we found some indications for
H-dominated plasma, and as a result, that the progenitor of N103B might have
been a Type II. The progenitor mass was estimated to be 13 Msun based on the
abundance patterns of Mg, Fe, and Ni relative to Si.
