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Single metal polluted white dwarfs with no dusty disks are believed to beactively accreting metals from a circumstellar disk of gas caused by thedestruction of asteroids perturbed by planetary systems. We report, for thefirst time, the detection of circumstellar Ca~II gas in absorption around theDAZ WD~1124-293, which lacks an infrared excess. We constrain the gas to $>$7$R_{\rm WD}$ and $<$32000~AU, and estimate it to be at $\sim$54~R$_{\rm WD}$,well within WD~1124-293's tidal disruption radius. This detection is based onseveral epochs of spectroscopy around the Ca~II H and K lines($\lambda$=3968\AA, 3933\AA) with the MIKE spectrograph on the Magellan/ClayTelescope at Las Campanas Observatory. We confirm the circumstellar nature ofthe gas by observing nearby sightlines and finding no evidence for gas from thelocal interstellar medium. Through archival data we have measured theequivalent width of the two photospheric Ca lines over a period of 11 years. Wesee $<$ 5-7\% epoch-to-epoch variation in equivalent widths over this timeperiod, and no evidence for long term trends. The presence of a circumstellargas implies a near edge-on inclination to the system, thus we place limits toshort period transiting planetary companions with R $>$ R$_{\rm \oplus}$ usingthe WASP survey. The presence of gas in orbit around WD~1124-293 implies thatmost DAZs could harbor planetary systems. Since 25-30\% of white dwarfs showmetal line absorption, the dynamical process for perturbing small bodies mustbe robust.

Detection of Weak Circumstellar Gas around the DAZ White Dwarf WD 1124-293: Evidence for the Accretion of Multiple Asteroids