# P2: The weak charge of the proton

### Research areas

• Experimental particle and hadron physics
• Theoretical particle and hadron physics
• Accelerator physics

The main objective of project P2 is the extraction of a precise value of the weak mixing angle, $$\sin^2 \theta_W$$, from a measurement of the parity violating (PV) asymmetry in elastic electron proton scattering, with an accuracy comparable to that of the existing LEP measurements of $$\Delta \sin^2 \theta_W = 0.00037$$ corresponding to a 0.16% relative uncertainty.
1. Design and construction of an integrating spectrometer for the measurement of the parity violating asymmetry in elastic electron-proton scattering based on integrating readout of quartz Cherenkov detectors, including a tracking system for the measurement of the average momentum transfer $$Q^2$$based on thin silicon pixel detectors, see the figure on the right.