MuCap: From first results to final precision on determining $g_P$

The MuCap collaboration recently reported the muon capture rate from the hyperfine singlet ground state of the $\mu p$ atom to be $\Lambda_S=725\pm17.4$ s$^{-1}$. The extracted nucleon induced pseudoscalar form factor, $g_P$, is $7.3\pm 1.1$. Subsequent runs contain 10 times more data and significant improvements have been made to the experimental apparatus. The aim is to reduce the final uncertainty of $\Lambda_S$ by a factor of three. The isotopic and chemical impurities in the protium target have been greatly reduced and an electrostatic kicker has been used to increase the effective data rate threefold. The experiment was upgraded with neutron detectors and full analog recording using custom built FADC modules for several critical detectors. I will present a description of the experimental upgrades and the status of the analysis, which with new data will reduce the overall uncertainty of $g_P$ to 7\%.