Example of a low-mass cluster (group), mJPC 2241−16656, detected by all three cluster finder algorithms in the miniJPAS/Chandra AEGIS field. The system, dominated by the galaxy SDSS J141719.86+523537.6 is at RA = 14:17:20 Dec = +52:35:38 and has photo-z = 0.238. Overlaid on the i-band image, white circles mark the position of galaxy members (within a window of ±4σ_l.o.s. – or 840 km s⁻¹) within R₂₀₀ (507 kpc; Evrard et al. 1996). These galaxies have membership probability larger than 88% as provided by the AMICO code. The contours in cyan show the extended X-ray emission in the 0.5–2 keV range obtained by the analysis of Chandra data in 0.5 dex surface brightness levels (for details refer to Erfanianfar et al. 2013). In the bottom right we show a zoom-in of the BCG surroundings for illustration. 1 arcmin corresponds to ≈230 kpc at the clusters redshift.