Soft $b$-hadron tagging for compressed SUSY scenarios

$b$-hadrons with transverse momenta too low to yield a calorimeter jet that can be efficiently identified by $b$-tagging techniques are ubiquitous in scenarios of compressed spectra of supersymmetric third generation particles. Three different techniques to tag low transverse momentum $b$-hadrons are described and characterised. One of them makes use of jets reconstructed only from tracks, while the other two explore the feasibility and performance of a vertex reconstruction not relying on any jet finding. The approaches are found to be complementary, with the latter two yielding better sensitivity to $b$-hadron transverse momenta in the 5-15 GeV range, and the former providing the best performance above 15 GeV.