Speaker
Description
We recently demonstrated the generation of ~10 GeV electron beams using only ~20 J of laser energy in a 30 cm long laser plasma accelerator (LPA) utilizing hydrodynamic optically field ionized (HOFI) plasma channels. However, shot-to-shot fluctuations in the output electron beam parameters were much larger than desired. For channel-guided LPAs, transverse focal position fluctuations at the entrance of the LPA significantly affect output electron beam parameters due to tight acceptance of the plasma channel. In this poster, we present results from an experiment at the BELLA PW laser system, where we correlated electron beam performance with the transverse pointing offset of the laser at the entrance of the plasma channel for a ~10 GeV LPA using a 40 cm long plasma target [1]. We investigated the sensitivity of HOFI plasma channels with respect to plasma channel size. We measured decreased laser red shifting and electron beam energy due to mispointed drive laser pulses. We show that a mispointed drive laser causes excitation and leakage of higher order modes, which reduces the energy available to drive a wakefield. Our results show that decreasing drive beam transverse pointing jitter, possible with active stabilization, could significantly improve the shot-to-shot stability of channel-guided LPAs.
[1] H. Tang et. al. https://doi.org/10.48550/arXiv.2604.25823
| Working group | WG1 |
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