... Archives . ... It refers to the spread in the measured energy of an incoming photon, and even astronomers often stumble over what it is and what it contains. ... The R edistribution M atrix F ile (RMF) is, at its most basic, a description of how the detector responds to incoming photons. ... The process of measuring the energy introduces a measurement error, which is encoded as the probability that incoming photons at energy E are read out in detector channels i . ... Comment ( RSS ) | ...