Lunch talk on Nov. 2, 2026

Decoding the Lensing Profile of a “Rotating” Cluster with Deep CFHT Imaging

Speaker: Yicheng Li (SAO)

Venue: SWIFAR Building 2111

Time: 12:45 PM, Monday, Nov. 2, 2026

Abstract: 

Galaxy kinematics provide insights into the dynamical structure of galaxy clusters, but apparent rotation can be difficult to interpret. In this talk, we present a multi-waveDecoding the Lensing Profile of a “Rotating” Cluster withlength study of RXCJ0110.0+1358 (z=0.058), a rotating cluster candidate, combining deep CFHT imaging, SDSS photometry, spectroscopic redshifts, and XMM-Newton observations. The catalog-selected galaxies form two pronounced concentrations in the southeast (SE) and northwest (NW), whereas the X-ray emission exhibits a single, smoothly extended component centered near the SE brightest cluster galaxy. Weak lensing identifies SE as the main detected mass concentration, with $M_{200}\sim10^{14},M_\odot$, spatially associated with the extended X-ray emission. No significant weak-lensing peak is detected at the NW optical center. The combined galaxy sample exhibits spatially correlated kinematic substructure and a rotation-like signal. Our results favor an interpretation in which this signal arises from jointly analyzing two galaxy populations that are separated on the sky and differ in mean redshift, highlighting the value of multi-wavelength observations in interpreting apparent cluster rotation.