Continuum-subtracted IRAM-PdBI spectra, maps, and position–velocity diagram of the CO(1–0) emission line of IRAS F10565+2448. Panels a) and b) show the spectra extracted from a circular aperture with a diameter of 10 arcsec and from the central pixel, respectively. For display purposes, the spectra are re-binned in channels of 27 km s^-1. In both panels the narrow core of the line is fitted with a single Gaussian function (red dashed line). Note the appearance, in both spectra, of broad CO wings up to ±600 km s^-1. c), d) Cleaned map of the emission integrated in the blue- and red-shifted CO(1–0) wings. Contours correspond to 1σ (1σ rms level of the two maps is 0.2 mJy beam^-1). The cross indicates the peak of the radio (VLBI) emission. The physical scale at the redshift of the source is 0.846 kpc arcsec^-1. e),f) Position–velocity diagram along the major axis of rotation. Inset f) highlights the rotation pattern traced by the narrow component of the CO(1–0) line. Contours are in steps of 1σ (up to 10σ) in panel e), and 5σ in panel f) (starting from 10σ in panel f)); negative contours are in steps of 1σ (magenta dashed lines). Each pixel corresponds to 1.3 arcsec × 53 km s^-1 in diagram e), and to 0.6 arcsec × 26 km s^-1 in the inset f).