In this paper we explore the effect of $delta$-ray emission, fluctuations in th e signal deposition on the detection of charged particles in silicon-based detec tors. We show that these two effects ultimately limit the resolution that can be achieved
by interpolation of the signal in finely segmented position-sensitive solid-state devices.
This report of the BOOST2012 workshop presents the results of four working groups that studied key aspects of jet substructure. We discuss the potential of the description of jet substructure in first-principle QCD calculations and study the accuracy
of state-of-the-art Monte Carlo tools. Experimental limitations of the ability to resolve substructure are evaluated, with a focus on the impact of additional proton proton collisions on jet substructure performance in future LHC operating scenarios. A final section summarizes the lessons learnt during the deployment of substructure analyses in searches for new physics in the production of boosted top quarks.
The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the
integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $mathrm{mathbf{mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $mathbf{e^+ e^-}$ collider.
