I performed the lockloss investigation for the lockloss which happened between 2025/10/04~05. The previous lockloss investigation was posted in klog35237.
During this period, there were 43 lockloss from the INCREASING_LAS_POWER state.  The plots are listed in DAC wiki and DAC wiki.

This time, I focus on the classification based on this klog. The template for the ndscope was prepared by Ushiba-san and stoped in /users/yuzu/lockloss/etc/lockloss_LSC-CARM.yml .

Lockloss during increasing the laser power (3 lockloss)

• 1443593873.8125
• 1443682893.8125 (with breathing of IMC_SERVO_MIXER_DAQ)
• 1443743993.9375 (with breathing of IMC_SERVO_MIXER_DAQ)

Lockloss during changing CARM_SERVO_IN1GAIN (20 lockloss)

The gain -22 is magic number.

• 1443604934.4375 (gain: -23 to -22)
• 1443605707.6875 (gain: -23 to -22)
• 1443610641.5625 (gain: -23 to -22)
• 1443620018.4375 (gain: -23 to -22)
• 1443631621.8125 (gain: -5 to -6 )
• 1443640639.9375 (gain: -23 to -22)
• 1443657184.3125 (gain: -23 to -22)
• 1443658610.4375 (gain: -23 to -22)
• 1443666833.9375 (gain -23 to -22)
• 1443671764.3125 (gain -23 to -22)
• 1443679082.6875 (gain -23 to -22)
• 1443681280.0625 (gain -23 to -22)
• 1443684021.3125 (gain -23 to -22)
• 1443696168.4375 (gain -23 to -22)
• 1443697865.8125 (gain -23 to -22)
• 1443698562.1875 (gain -23 to -22)
• 1443699250.8125 (gain -23 to -22)
• 1443721521.4375 (gain -23 to -22)
• 1443741097.9375 (gain -23 to -22)
• 1443742363.3125 (gain -23 to -22)

Lockloss after finishing the process in INCREASING_LAS_POWER state and after breathing of IMC_SERVO_MIXER_DAQ (5 lockloss)

• 1443592229.0625
• 1443596856.0625
• 1443604190.4375
• 1443678158.8125
• 1443693511.5625

Lockloss after finishing the process in INCREASING_LAS_POWER state and after the glitches of IMC_SERVO_MIXER_DAQ (1 lockloss)

• 1443722483.9375 (but during process of increasing the laser power)

Lockloss after finishing the process in INCREASING_LAS_POWER state, but no special feature (4 lockloss)

We are calling this lockloss as the sudden lockloss... We can't find clue of these lockloss now.
For these lockloss, I checked the Q-spectrogram of PEM sensors in PSL room and channels shown in fig, by using Pastavi. But, there was no special fetures.

• 1443619163.1875
• 1443656380.3125
• 1443669748.9375
• 1443730826.4375

Oscillating of suspensions or alignment drift (2 lockloss)

• 1443712735.5625
• 1443728728.5625