Preparation of the green light reference for IR injection in the FC
This morning we continued the alignment of the IR beam on the filter cavity.
Moving SQB1_M21, we observed the IR beam impinging on the lower edge of the filter cavity input mirror (FCIM). The beam was centered in the horizontal degree of freedom (reference positions of the actuators: M21_H: -108100, M21_V: -18200 ), then we moved only the vertical. The idea was to center the FCIM using SQB1_M21 and overlap the beam with the green on SQB2, using SQB1_M22.
We improved the green beam centering with fine tilt of GM11 and SQB1_M1 (referece position of the actuators: GM11_H: 550, GM11_V: 6540, SQB2_M1_H: 19788, SQB2_M1_V -11908). Then we optimized the position of the green camera on FCEB (GCam) and of the photodiode (GPD) on the same bench.
On GPD we where able to see the peaks and we optimized them by moving the input mirror (reference positions: MAR_TX=21.82, MAR_TY=-3300.16, TX_set: 30, TY_set: -3300). We will add a comment with relative figures.
Moreover we positioned the camera and the photodiode on FCEB also for the IR, using the residual reflection of the green beam from the dichroic mirror.
garaventa - 21:57 Thursday 10 June 2021 (52115)
Print this report
Optimization of peaks in transmission to the FCEM (photodiode FCEB_GR_PD_DC).
Images attached to this comment