NGC4839
We propose to observe the inner part of the ram pressure stripped tail of the galaxy group NGC 4839, which is infalling into the Coma cluster, for 190ks with Resolve. A surface brightness fluctuation analysis of the inner tail with Chandra has revealed a turbulent Mach number of 0.5, which should result in a velocity dispersion of 320km/s. The low redshift of the system makes this the brightest stripped tail in X-rays and mitigates the complicating factor of XRISM's large PSF, which combined with its high metallicity of 0.8 Z_solar makes it the only tail whose velocity dispersion can be measured with a realistic exposure time with XRISM. This system therefore provides a unique opportunity to probe the generation of turbulence due to merging activity in galaxy clusters.
obsid = 202001010 / Unique Observation/Sequence Number
object = NGC4839 / Object name
pi_name = WALKER STEPHEN / Proposal Principal Investigator Name
ra = 194.300106375452 / Right Ascension (Pointing Position) (deg)
dec = 27.4887877613418 / Declination (Pointing Position) (deg)
roll_angle = 133.825069136872 / Roll Angle (deg)
start_time = 2025-12-01T16:11:04 / Start Time of the Observation
stop_time = 2025-12-04T19:24:04 / Stop Time of the Observation
exposure = 137095.24848 / Effective Total Observation Exposure (s)
public_date= 2099-12-31 / Public Date