HRC Instrument Information

Diagram of HRC-I and HRC-S chips

The High Resolution Camera (HRC) is a microchannel plate (MCP) instrument with two detectors, the HRC-I optimized for imaging and the HRC-S for spectroscopy. The HRC-I has the largest field of view aboard Chandra. The HRC energy range (0.06-10 keV) extends below that of ACIS, (0.08-10 keV) but with less intrinsic spectral resolution (ΔE/E~1). The HRC-S is well-suited to serve as the readout for the Low Energy Transmission Grating (LETG). It can also be used in a very fast timing mode.

The instrument layout is shown to the right. At 30x30 arc min, the HRC-I FOV is the largest aboard Chandra, larger than the ACIS wide field imaging FOV of 16.9x16.9 arc min. The HRC-I aim point is situated in the middle of the detector for the best image quality. The HRC-S FOV is 6x99 arc min and the aim point is slightly offset to accomodate different wavelengths of the grating dispersed spectrum. For high-precision timing observations, only the center MCP segment is used to generate triggers, lowering the effective area to 6x30 arc min.

A complete description of HRC is given in the Proposers' Observatory Guide.

The table below summarizes the three most common HRC operating modes.

Common HRC Configurations
Science Mode Detector FOV (arcmin) Energy Resolution Time Resolution
High-Resolution and Wide-Area Imaging HRC-I 30x30 ΔE/E=1 over energy range 0.08-10.0 keV
High-Resolution Spectroscopy with Wide Wavelength Coverage HRC-S/LETG 3.4x991 see LETG 10 ms
Timing Mode HRC-S 6x30 16 µs
Notes:1. Due to the high background exceeding the telemetry limit, a spectroscopy region has been defined by implementing an edge blanking feature.