RA3. Experimental Equipment - New Dual MCP Fast Timing Detector
(K. Schmitt, Spokesperson)
A variation of the foil+MCP base timing detector has been developed to address the lower efficiencies for detecting ions with low specific energy loss (DE/DX) . The system features two micro-channel plate (MCP) detectors viewing the opposing surfaces of a single foil. This allows for monitoring the detection efficiency in-beam as well as extracting a fast timing signal with significantly increased efficiency.
In this detector secondary electrons are ejected as ions pass through a thin carbon or aluminized Mylar foil. Electric fields guide the electrons emitted from the foils toward the surface of a micro-channel plate detector assembly where fast multiplication of the electron current takes place. The amplified electron current is collected at a metal anode and used to provide a fast timing signal.
Efficiency is measured using the count rates from the individual anodes and the count rate of signals that are coincident in time. Since the probability that signals coincide is the product of the efficiencies of the individual detectors, the efficiency of one detector is the coincident count rate divided by the count rate of the other detector.
The first experiment to take advantage of this detector will be
10Be(d,p) as part of a long-lived RIB campaign scheduled for this fall at HRIBF. A
position-sensitive Dual MCP will be constructed in the coming months.