We present here new observations of the eccentric debris ring surrounding the Gyr-old solar-type star HD 202628: at millimeter wavelengths with ALMA, at far-infrared wavelengths with textit{Herschel}, and in scattered light with textit{HST}. The ring inner edge is found to be consistent between ALMA and textit{HST} data. As radiation pressure affects small grains seen in scattered-light, the ring appears broader at optical than at millimeter wavelengths. The best fit to the ring seen with ALMA has inner and outer edges at $143.1 pm 1.7$ AU and $165.5 pm 1.4$, respectively, and an inclination of $57.4^circ pm 0.4$ from face-on. The offset of the ring centre of symmetry from the star allows us to quantify its eccentricity to be $e=0.09_{-0.01}^{+0.02}$. This eccentric feature is also detected in low resolution textit{Herschel}/PACS observations, under the form of a pericenter-glow. Combining the infrared and millimeter photometry, we retrieve a disk grain size distribution index of $sim -3.4$, and therefore exclude in-situ formation of the inferred belt-shaping perturber, for which we provide new dynamical constraints. Finally, ALMA images show four point-like sources that exceed 100$,mu$Jy, one of them being just interior to the ring. Although the presence of a background object cannot be excluded, we cannot exclude either that this source is circumplanetary material surrounding the belt-shaper, in which case degeneracies between its mass and orbital parameters could be lifted, allowing us to fully characterize such a distant planet in this mass and age regime for the very first time.
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