Tp is typically {HEAD ~ between 20 and 300 seconds} and {TAIL ~ αt} between 0 and 5 
Tp is typically { HEAD ~ between 20 and 300 seconds } and { TAIL ~ αt } between 0 and 5
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH