CYG_X-2
Cyg X-2 was observed as part of the XRISM in-flight calibration campaign for the Resolve point spread function. Although these data were not originally intended for spectroscopy---resulting in low signal-to-noise and several analytic uncertainties---we have nonetheless succeeded in resolving the complex Fe K-band emission-line components likely coming from the accretion disk corona. In this proposal, by achieving substantially higher S/N with an on-axis observation, we aim to reject models that remain viable with the current data, the disk line model. We also will compare it with other already-observed Z-track sources and establish a comprehensive picture of mass inflow and outflow in neutron star low-mass X-ray binaries, including Fe-K absorption lines by the ultrafast outflow (v/c=0.29).
obsid = 202054010 / Unique Observation/Sequence Number
object = CYG_X-2 / Object name
pi_name = MIZUMOTO MISAKI / Proposal Principal Investigator Name
ra = 326.171648082891 / Right Ascension (Pointing Position) (deg)
dec = 38.3213969088932 / Declination (Pointing Position) (deg)
roll_angle = 251.761070104212 / Roll Angle (deg)
start_time = 2025-11-23T00:49:04 / Start Time of the Observation
stop_time = 2025-11-24T01:20:04 / Stop Time of the Observation
exposure = 46019.940784 / Effective Total Observation Exposure (s)
public_date= 2099-12-31 / Public Date