W49B_West
The Suzaku's discovery of recombining plasma in supernova remnants (SNRs) was a surprise because it is never expected in the fiducial Sedov model. We propose to observe the brightest recombining SNR W49B to reveal the origin of this new class of SNRs based on the high-resolution spectroscopy using XRISM/Resolve. We will identify the cooling process that formed the recombining state based on measurements of the electron temperature, ion temperature, and charge-state distribution. We will also constrain the progenitor type that regulates the SN environment, by bias-free measurements of the ejecta mass ratios of the Fe-group elements. Additionally, as an ideal goal, we will search for the signature of interaction with supra-thermal electrons and constrain the injection efficiency.
obsid = 300056010 / Unique Observation/Sequence Number
object = W49B_West / Object name
pi_name = Collaboration XRISM / Proposal Principal Investigator Name
ra = 287.779376253502 / Right Ascension (Pointing Position) (deg)
dec = 9.11004019004261 / Declination (Pointing Position) (deg)
roll_angle = 67.9997878929557 / Roll Angle (deg)
start_time = 2024-04-30T22:58:04 / Start Time of the Observation
stop_time = 2024-05-08T08:43:04 / Stop Time of the Observation
exposure = 323190.56251362 / Effective Total Observation Exposure (s)
public_date= 2025-08-31 / Public Date