OPHIUCHUS_CLUSTER_NW
Recent XRISM observations of the Ophiuchus galaxy cluster revealed a puzzling contradiction: despite morphological evidence of core disruption including cold fronts, the velocity structure is remarkably quiescent (\sigma_v ~ 115 km s^-1). Two scenarios have been proposed: (1) sloshing motion approaching a turning point with minimal velocities, or (2) core motion nearly parallel to the sky plane. We propose a 300ks XRISM observation of the western core regions, where preliminary analysis suggests elevated velocity dispersions. This will distinguish between the scenarios and offer a full understanding of the dynamics and evolution of this unique, high-temperature, cool-core cluster.
obsid = 203008010 / Unique Observation/Sequence Number
object = OPHIUCHUS_CLUSTER_NW / Object name
pi_name = FUJITA YUTAKA / Proposal Principal Investigator Name
ra = 258.062209208587 / Right Ascension (Pointing Position) (deg)
dec = -23.3392666444877 / Declination (Pointing Position) (deg)
roll_angle = 274.83997423179 / Roll Angle (deg)
start_time = 2026-09-07T12:26:04 / Start Time of the Observation
stop_time = 2026-09-08T10:31:04 / Stop Time of the Observation
exposure = 43576.259833 / Effective Total Observation Exposure (s)
public_date= 2099-12-31 / Public Date