The X-ray emission from the young supernova remnant ( SNR ) SNR N 103B is measured and analysed using the high-resolution cameras and spectrometers on board XMM-Newton and Chandra .
The spectrum from the entire remnant is reproduced very well with three plasma components of kT _ { e } = 0.55 , 0.65 , and 3.5 keV , corresponding roughly to line emission by the O-K , Fe-L , and Fe-K species , respectively .
Narrow band images reveal different morphologies for each component .
The kT _ { e } = 0.65 keV component , which dominates the emission measure ( 4.5 \times 10 ^ { 65 } m ^ { -3 } ) , is in ionisation equilibrium .
This provides a lower limit of 3000 yrs to the age of the remnant , which is considerably older than the previously assumed age of the remnant ( 1500 yrs ) .
Based on the measured energy of the Fe-K feature at 6.5 keV , the hot ( 3.5 keV ) component is found to be recently shocked ( \sim 200 yrs ) and still ionising .
The high elemental abundances of O and Ne and the low abundance of Fe could imply that SNR N 103B originated from a type II supernova ( SN ) rather than a type Ia SN as previously thought .