Deriving an X-ray luminosity function of dwarf novae based on parallax measurements

We have derived an X-ray luminosity function using parallax-based distance measurements of a set of 12 dwarf novae, consisting of Suzaku, XMM-Newton and ASCA observations. The shape of the X-ray luminosity function obtained is the most accurate to date, and the luminosities of our sample are concentrated between similar to 10(30) and 10(31) erg s(-1), lower than previous measurements of X-ray luminosity functions of dwarf novae. Based on the integrated X-ray luminosity function, the sample becomes more incomplete below similar to 3 x 10(30) erg s(-1) than it is above this luminosity limit, and the sample is dominated by X-ray bright dwarf novae. The total integrated luminosity within a radius of 200 pc is 1.48 x 10(32) erg s(-1) over the luminosity range of 1 x 10(28) erg s(-1) and the maximum luminosity of the sample (1.50 x 10(32) erg s(-1)). The total absolute lower limit for the normalized luminosity per solar mass is 1.81 x 10(26) erg s(-1) M-circle dot(-1) which accounts for similar to 16 per cent of the total X-ray emissivity of cataclysmic variables as estimated by Sazonov et al.