Backscattering of secondary particles into the ILC detectors from beam losses along the extraction lines

At the International Linear Collider (ILC) the beams will be focused to extremely small spot sizes in order to achieve the desired luminosity. After the collision the beams must be brought to the dump with minimal losses. In spite of all the attention put into the design of the extraction line, the loss of some disrupted beam particles, beamstrahlung or synchrotron radiation photons is unavoidable. These losses will generate low-energy secondary particles, such as photons, electrons and neutron, a fraction of which can be back-scattered towards the Interaction Point (IP) and generate backgrounds into the detector. In this paper we present an evaluation of such backgrounds, using the BDSIM [1] and Mokka [2] simulations. The event reconstruction in the detector is made with the Mar- linReco package from the Marlin tool [3].