The kernel is not a stationary object in memory that can be extracted. It's working, which means it's changing all the time with values being modified in accordance with its numerous processes mediating the hardware and software. The nearest one can get, I imagine, is a kernel core dump which is not a bootable or usable kernel but rather something available for analysis.
On thinking further about it, if you wanted to have the kernel, but were unable to get the vmlinuz-... file of it in /boot, the next best thing might be getting the kernel config file so that it could be used to compile the kernel that became the system's /boot/vmlinuz-...