Advanced Composition Explorer (ACE) Particle Composition and Flux Browse Data

This pace data is at L1 (approx. 1.5 million km upstream along earth-sun line). ACE browse data are designed for monitoring large scale particle and field behavior and for selecting interesting time periods. The data are automatically generated from the spacecraft data stream using simple algorithms provided by the instrument investigators.

They are not routinely checked for accuracy and are subject to revision. Use these data at your own risk, and consult with the appropriate instrument investigators about citing them. Browse parameters are a subset of measurements by the ACE instruments which are created at the Science Center during level one processing.

They are delivered to the public domain as soon as possible. Their purpose is to allow monitoring of the solar wind and large-scale particle and magnetic field behavior, and selection of interesting time periods for more intensive study. Interesting time periods might include solar energetic particle events, or the passage of an interplanetary shock.

An additional use of the browse parameters is to investigate relationships between the data from the various ACE instruments, and between ACE data and data from other sources. The browse parameters include unsectored fluxes of ions at many different energies and electrons at a few energies. They also include the interplanetary magnetic field, and solar wind parameters such as proton speed and temperature.

They therefore furnish a very abbreviated description of what is being observed by the ACE instruments, without the relatively high cost of storing and analyzing all the level one data. Eventually they may be supplemented with event data from the particle detectors, but experience with the flight data is a prerequisite for delivering useful products of that type. See: srl.caltech.edu/ACE/ASC/browse/browse_info.html for more information.