This work package will evaluate the inherent constraints on beampipe design for various options for the high luminosity insertions at HL-LHC. It will take into account physics requirements at the interaction point and in the forward region along with LHC machine constraints. Mechanical, electromagnetic and vacuum calculations will be performed to verify the viability of various design options. It will also evaluate via simulations the fluence, dose rate, integrated dose and activation to be expected in various regions of the experimental cavern, for the principal HL-LHC design options being considered and for various shielding configurations. The backgrounds and particle fluences induced in triggering, monitoring and physics detectors for various modes of HL-LHC operation will be evaluated, taking into account both routine operations and various pathological conditions.
For the luminosities expected at HL-LHC, the effect of beam-induced radiation upon the detectors and materials which may be deployed in the experimental areas will be determined to inform the choice of detector technologies, and the design of shielding. Magnetic fields and forces affecting various parts of the experiment structure, detectors and ancillary systems, will be calculated based on various designs of the HL-LHC experimental insertion and on various compatible mechanical and shielding structures for the experiments. Practical shielding configurations will be designed and analysed based upon radiation calculations, and taking into account the radiation tolerance of equipment and the calculated magnetic fields and forces. Instrumentation suitable for monitoring beam conditions in experiments at HL-LHC, including instantaneous backgrounds, fluences, dose-rates and luminosity, along with integrated doses and integrated luminosity will be designed and prototyped.