The Extremely High Concentration of the Fossil Group NGC 6482

Although fossil systems are thought to be very old, only a few displayaboveaverage concentration parameters. Recently, using Chandra and Suzaku dataextending out to R2500 of the wellstudied fossil group NGC 6482, we measuredc200 that exceeds the mean LCDM cM relation by 6 sigma with respect to theintrinsic scatter and by 3.5 sigma with respect to the measurement error. Theextreme outlier status, if confirmed, would pose a challenge to LCDM galaxyformation, since the scatter in the cM relation is robust and insensitive tocosmological parameters. We propose a deep XMMNewton observation of NGC 6482 toobtain precise measurements of the gas properties out to R500, particularly thetemperature, to verify the high c200 and cement its status as the most extremely evolved fossil system known. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]