Extensive photometry of V1838 Aql during the 2013 superoutburst

We present an in-depth photometric study of the 2013 superoutburst of the recently discovered cataclysmic variable V1838 Aql and subsequent photometry near its quiescent state. A careful examination of the development of the superhumps is presented. Our best determination ofthe orbital period is P_orb = 0.05698(9) days, based on the periodicity of early superhumps. Comparing the superhump periods at stages A and B with the early superhump value we derive a period excess of ɛ=0.024(2) and a mass ratio of q=0.10(1). We suggest that V1838 Aql is approaching the orbital period minimum and thus has a low-mass star as a donor instead of a substellar object.