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Phase-resolved Crab Studies with a Cryogenic Transition-Edge Sensor Spectrophotometer



R. W. Romani, Aaron J. Miller, B. Cabrera, Sae Woo Nam, John M. Martinis


We are developing time- and energy-resolved near-IR/optical/UV photon detectors based on sharp superconducting-normal transition edges in thin films. We report observations of the Crab pulsar made during prototype testing at the McDonald 2.7 m with a fiber-coupled transition-edge sensor (TES) system. These data show substantial (δα 0.3), rapid variations in the spectral index through the pulse profile, with a strong phase-varying IR break across our energy band. These variations correlate with X-ray spectral variations, but no single synchrotron population can account for the full spectral energy distribution. We also describe test spectrophotopolarimetry observations probing the energy dependence of the polarization sweep; this may provide a new key to understanding the radiating particle population.
Astrophysical Journal


detectors, instrumentation, pulsars


Romani, R. , Miller, A. , Cabrera, B. , Nam, S. and Martinis, J. (2001), Phase-resolved Crab Studies with a Cryogenic Transition-Edge Sensor Spectrophotometer, Astrophysical Journal (Accessed February 25, 2024)
Created December 9, 2001, Updated October 12, 2021