Abe, Marc, Matteo

This morning, we installed the 1cm thick SHINKOSHA sample.

We recentered the beam dump on the laser unit and covered back this unit.

Then, we increased the power to ~300 mW to check the sample center and inclinaison.

We checked its X,Y and Z centers :

X center = 398.195 mm

Y center = 121.5 mm

Z center = 51.4 mm

Then, we checked the z center at the left, right, bottom and top position of the sample with extremal positions separated by 13 cm.

We found a 0.8 mm vertical tilt of the mirror and a 0.4 mm horizontal tilt.

Finally, we increased the laser power to 3.46W and started the measurement of absorption map of this sample.

We also did a preliminary evaluation of the absorption as

AC = 3.6e-3 V;
DC = 4.71 V;
P_in = 3.46 W;
P_t = 2.94 W;
T_sample = P_t/P_in;
R_bulk =0.7414 W/cm;
mat_correction=3.34;

abs = AC/(DC*P_in*sqrt(T_sample)*R_bulk)*1e6*mat_correction ~1080 ppm/cm