TNG u′-band image and MEGARA spectroscopy of the blue stellar stream in the NGC 7241 halo. Top: zoom-in on the region in the position of the stream taken from the TNG u′-band image. It is centered in the compact object targeted in our campaign as the possible progenitor of the stream. The image also shows a second fainter overdensity at ∼5 arcsec northwest (top right) labeled as the stream core. Middle: heliocentric radial velocity obtained from the emission in Hβ line detected in the MEGARA LR-B data. Two emission sources are observed, a compact one in the center and the second in the top right corner. The g-band DESI Imaging Legacy data contours are overplotted. The g-band contours shown correspond to the range between 28 and 31 AB mag arcsec⁻² and are equally spaced in linear (flux) scale. Bottom: continuum image of the stream nucleus candidate obtained after averaging the flux from the MEGARA LR-B datacube in the (rest-frame) wavelength range between 480–484 nm and 487–495 nm. The same g-band contours as those used for panel b, except for those brighter than 28.7 AB mag, are plotted here.