Position-Sensitive Transition-Edge Sensors (PoSTs)
A Position-Sensitive Transition-Edge Sensor (PoST) is a novel
microcalorimeter we are developing for large format imaging
spectrometers. The idea is very simple: several absorbers are
strung together thermally with a thermal conductance Ga
between each. TES thermometers are placed at either end of the
absorber chain and connected to a cold bath at temperature Tb
through a thermal conductance G. When a photon hits the PoST,
heat flows to either end and is readout by the TESs. The
position of the photon is inferred from difference in pulse
heights between the two TESs. The energy of the X-ray is
determined from the sum of the two pulses. A PoST with 10
absorbers and two TESs would provide 5 times more pixels than
a single-pixel TES.
