About LET; all are false except (NOT RELATED TO PHARMACOLOGY)

LET (linear energy transfer)- it is the amount of energy deposited per unit length. Given as Kev/ micrometre. It is highest for alpha paicle (high LET), low for beta paicles and gamma emissions (Low LET). It is a propey of the radiation. OER (oxygen enhancement ratio )is the ratio of quantity of radiation required to kill tumour cells in the absence of oxygen to the quantity of radiation required to kill same amount of tumour cells in the presence of oxygen. OER is low for high LET radiations (OER= 1) and high for low LET radiations(OER= 2-3).