The evaluated value {HEAD ~ Smn=Mm×} is calculated from a plurality of different write power compensated values Pcn , the write power Pwm, and {TAIL ~ the modulation} Mm 
The evaluated value { HEAD ~ Smn = Mm× } is calculated from a plurality of different write power compensated values Pcn , the write power Pwm , and { TAIL ~ the modulation } Mm
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH