Release Notes for ETC 21.1

New Features

Welcome to ETC 21.1. This version of the ETC implements several new features, notably:

General

• New normalization option: normalize to ABmag in observation band
• Improved sun angle coverage for zodiacal light: now consistent with APT

Under the hood

• Instrument data values have been updated for Cycle 21.1.

Resolved Issues

This version resolves the following issues for ACS and COS:

ACS

• Spectroscopic ETC calculations for extended targets now correctly estimate the background rate and counts. (This Known Issue was incorrectly reported as a general, rather than ACS specific, issue.)

COS

• The wavelength range over which the global countrate calculation is performed is no longer truncated at 3500A for COS NUV imaging; it now extends to 12000A.
• The COS NUV spectroscopic calculations now correctly take into account the circular shape of the COS apertures.

Known Issues

Please see the News and Known Issues page for known issues with this release.