A detailed analysis of the most relevant sources of phase noise in an atomic interferometer is carried out, both theoretically and experimentally. Even a short interrogation time of 100 ms allows our cold atom gravimeter to reach an excellent short term sensitivity to acceleration of $1.4\times 10^{-8}$g at 1s. This result relies on the combination of a low phase noise laser system, efficient detection scheme and good shielding from vibrations. In particular, we describe a simple and robust technique of vibration compensation, which is based on correcting the interferometer signal by using the AC acceleration signal measured by a low noise seismometer.Comment: 30 pages, 14 figure

We present here an analysis of the sensitivity of a time-domain atomic interferometer to the phase noise of the lasers used to manipulate the atomic wave-packets. The sensitivity function is calculated in the case of a three pulse Mach-Zehnder interferometer, which is the configuration of the two inertial sensors we are building at BNM-SYRTE. We successfully compare this calculation to experimental measurements. The sensitivity of the interferometer is limited by the phase noise of the lasers, as well as by residual vibrations. We evaluate the performance that could be obtained with state of the art quartz oscillators, as well as the impact of the residual phase noise of the phase-lock loop. Requirements on the level of vibrations is derived from the same formalism.