macOS boot issue loops on attached error - logs: panic(cpu 1 caller 0xffffff8005f29998)

Hello,

• iMac (21,5 inch, end 2013),
• 8 GB RAM,
• Intel i5 + Iris graphical card,
• Boot on external SSD (dual boot macOS Catalina),
• Latest macOS updated

Error:

At boot, it loops (re-boot) with attached error.

Logs errors:

I get messages such as :

• panic(cpu 1 caller 0xffffff8005f29998)...
• panic(cpu 3 caller ....

Partitions:

On the same SSD, there are 2 partitions :

This happens only on one of the macOS Catalina partition, on the other one (only for test, small amount of disk space) this never happens.

If this iMac works fine with the test macOS Catalina partition (no boot issues) I assume PRAM test will not help in this case.

Thank you in advance for your help

Kind Regards,

Pet.