For reasons that are relatively unimportant at this point, I wound up running sgdisk --zap on all 3 drives of my raid5 array, which I had created some time ago via the bios intel raid interface, without realizing that this would completely destroy the raid array. The data is still there, and I can still see the partitions if I examine the disks in gparted, however I cannot access any of the data, and I'm unsure how to proceed. Can anyone tell me how I might safely rebuild the raid array? For reference, here is the info on the drives as reported by mdadm --examine
/dev/sdb:
MBR Magic : aa55
Partition[0] : 2883020800 sectors at 2048 (type 07)
Partition[1] : 1024002050 sectors at 2883024894 (type 05)
/dev/sdc:
MBR Magic : aa55
Partition[0] : 4294967295 sectors at 1 (type ee)
/dev/sdd:
MBR Magic : aa55
/dev/sdb:
MBR Magic : aa55
Partition[0] : 2883020800 sectors at 2048 (type 07)
Partition[1] : 1024002050 sectors at 2883024894 (type 05)
/dev/sdc:
MBR Magic : aa55
Partition[0] : 4294967295 sectors at 1 (type ee)
/dev/sdd:
MBR Magic : aa55