Soft muon tagging and Dstar/mu correlations in 7 TeV collisions with ATLAS

Muons from the semi-leptonic decay of bottom quarks offer several opportunities to study b-tagging in jets. We describe a tagging algorithm which identifies muons in jets and compare its performance on real data to Monte Carlo simulation: results are found to be in good agreement with the expectations. A fairly pure sample of bottom jets can be also selected by reconstructing the semi-leptonic decay of bottom quarks in the $D^{\star}\mu$ final state. This sample can be used to cross-check ``lifetime'' tagging algorithms or to measure their efficiency; the general method is outlined.