X_PERSEI
Clumping is known to occur in the circumstellar environments of massive binaries and may also be present in Be discs. In this context, fluorescent Fe~K$\alpha$ emission can provide a sensitive probe of cold, dense structures embedded in a more tenuous medium. X Persei spectra are typically poor in emission lines, and to our knowledge no persistent narrow Fe~K$\alpha$ line has been reported. However, NS spin phase-resolved spectroscopy of \xmmnewton and \chandra\ data revealed transient Fe~K$\alpha$ signatures that are otherwise diluted in phase-averaged spectra. Over the same spin cycle, the continuum components vary consistently with emission from an accretion-powered hotspot on the NS surface, whereas the origin of the soft excess remains unclear. These studies are currently limited by
obsid = 203153010 / Unique Observation/Sequence Number
object = X_PERSEI / Object name
pi_name = SANJURJO GRACIELA / Proposal Principal Investigator Name
ra = 58.8440942440961 / Right Ascension (Pointing Position) (deg)
dec = 31.0455682589562 / Declination (Pointing Position) (deg)
roll_angle = 73.3279747026022 / Roll Angle (deg)
start_time = 2026-09-20T19:24:04 / Start Time of the Observation
stop_time = 2026-09-21T02:21:04 / Stop Time of the Observation
exposure = 11247.017814 / Effective Total Observation Exposure (s)
public_date= 2027-10-07 / Public Date