This afternoon, in agreement with Michal, we spent approximately 3 hours working on IPATSiA.
With the ITF in LN3, we carried out the following tasks:
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Completed the electronic cabling for the switching on of the CO₂ laser, two power meters, and the flip mirror, without unlocking the ITF.
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Verified that the chiller can effectively cool down the laser --> test passed.
Below is the list of actions performed in chronological order, with approximate timings:
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14:25 UTC: Chiller ON
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14:25 UTC: Laser electronics ON
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14:33 UTC: ITF unlocked from LN3
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14:40 UTC: CO₂ laser ON
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15:20 UTC: ITF locked in LN3
We started shining the mirror with the CO2-PA at around 15:32UTC with the minimal power (estimated at less than 10 mW on the TM). As shown in Fig. 1, the thermo-camera revealed a spot initially located on the external baffle.
By tuning the position of the last mirror (MX) and slightly increasing the power (~30 mW), at 15:55:13 UTC we managed to observe the spot on the edge of the TM (see Fig. 2).
We kept the laser on the TM for about 10 minutes, then moved to a more centered point (Fig. 3). At 16:11:00 UTC we closed the flip mirror for 5 minutes to allow the mirror to cool down.
At 16:17:26 UTC, we opened the flip mirror again for 10 minutes (see Fig. 4).
We moved further toward the center and, after another thermalization period (CO2-PA off at 16:30:41 for 5 minutes), we projected the PA again onto the TM for 20 minutes (see Figs. 5–7).
We stopped at 16:56:46 UTC and completely switched off IPATSiA:
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16:58 UTC: CO₂ laser OFF
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16:59 UTC: Chiller OFF
See Figure 8 for a summary of the actions performed.
