Superhump and outburst activity of the cataclysmic variable RZ LMi in the U- and optical passbands

An analysis of the new U , B , V , R C , I C -photometry of the cataclysmic variable RZ LMi obtained in 2016–17 showed the largest ( U − B ) colour excess in quiescence as well as during the decline of brightness, associated with the outbursts activity. The smallest ( U − B ) colour excess was found during the brightness increase from the quiescence. In contrast to the ( U − B ) colour index, the ( B − V ) , ( V − R C ) , ( R C − I C ) colour indices exhibits the largest colour excesses near the maximum of the outburst and the smallest during the quiescence. The ( B − V ) colour index showed also a large excess 1–2 days before a minimum. The detailed study of superhumps during the maximum of activity reveals the largest ( U − B ) colour excess at the time of the minimum brightness of superhumps. The ( B − R C ) colour index exhibits a similar behaviour, but with a phase shift of + 0.1 – + 0.2 period of superhumps. The tracks in two-colour and colour-magnitude diagrams during superoutbursts are compared with the data for other cataclysmic variables during their outbursts as well as with published theoretical calculations.