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.|