Astronomy & Astrophysics

Table 1: Comparison of countrates $\Lambda$ obtained from RASS-3 and as given in the 2RXP catalogue. Column 1: minimum countrate (RASS-3). Column 2: number of X-ray sources. Column 3: average difference $({\rm ctr(RASS3)}$ minus ${\rm ctr(2RXP)})$ . Column 4: standard deviation of the countrate differences. See also Fig. 8.