Charge-coupled devices with fast timing for astrophysics and space physics research

摘要: ABSTRACT A charge coupled device is under development with fast timing capability (15 millisecond full frame readout, 30microsecond resolution for measuring the time of individual pixel bits). The Fast Timing CCD will be used in conjunctionwith a CsI microfiber array or segmented scintillator matrix detector to detect X-rays and gamma rays submillimeterposition resolution. initial application conjunction coded aperture hard X-ray/gamma ray astronomyinstrument. We describe concept readout architecture device.Key Words: Hard X-ray, ray, devices, resolution, 1. INTRODUCTION Charge devices (CCDs) are, many ways, ideal light detectors. They are high reliable analogsampled good quantum efficiency over wide range wavelengths from infrared X-ray regime.Typically, however, scanning limited video rates (30 frames/second). For applications requiring dynamicimage capture (e.g., high-speed automated inspection on manufacturing packaging lines, short-duration exposures rapidlymoving objects, surveillance moving vehicle aircraft, high-resolution microscope studies transient phenomenaunder conditions where mechanical shutter would induce unacceptable vibrations), presently available CCDs may tooslow. have numerous viewing images when either subject camera inmotion. spectroscopic (in non-destructive testing, medical imaging, fluorescence studies, astronomy,material science surface physics measurements) no more than single photon/pixel must detected each readoutin order measure photon energy, capable isolating photons extremelyuseful. In long-duration low intensity contrast objects (for example, radiological searches smalllesions presence motion induced by patient's breathing, extended satellite observations faint astronomicalobjects an ionizing cosmic background passing through detector), allowthe final image summed discrete, which blurring due can beremoved events vetoed. currently developing 10-30 sec timingresolution suitable such applications.In astronomy, observation highly variable sources like binaries AM Her stars requires timeresolution usually only photomultiplier tubes. Occultations require timing, wide-anglesearches optical counterparts bursts benefit as well. Althoughphotomultipliers nanosecond capability, they not simultaneous wide-field imaging. addition,photomultipliers rapidly becoming less at large telescope facilities being replaced CCDs.The case X-ray/y-ray astronomy (20-600 keV) offers interesting described Sec. 2. best angularresolution so far these energies has been 13' arc obtained SIGMA experiment'. Our groupis Minute Arc Resolution Gamma Imaging Experiment (MARGIE), apertureinstrument designed field view minute resolution2'3. MARGIE employs room-temperature cadmiumzinc telluride (CZT) readout45 energy 20-200 keY. At higher (50-600 keY) (Tl)microfibers2'6 detector7 serves active detector, scintillation theCsI crystal silicon array. Millisecond desirable observing pulsars