Luminosity Measurement at an Electron Ion Collider*

The physics program of a  future Electron Ion Collider (EIC) requires high precision measurement of the instantaneous and integrated luminosity.  For polarized light ions, the luminosity must be measured independently for each polarization combination of the two beams.  Also, the polarization dependence of the luminosity measure must be understood.  The luminosity measurement techniques must  be applicable with stable precision across the entire periodic chart of possible ion beam species.  Relative luminosity, tagged to the individual stored bunches, is also required.

I will review some possible techniques to measure the luminosity, and discuss the associated detector requirements.  Possible techniques include: Van der Meer scans (V. Balagura, NIM A 654 (2011) 634); QED Compton (E. Aaron,H1 collaboration, Eur. Phys. J. C 72 (2012) 2163); Bremsstrahlung total absorption Calorimetry and Pair-Spectrometer (L. Adamczyk et al.,Nucl.Instrum.Meth. A744 (2014) 80).