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Metadata Updated: December 6, 2023

The Cassini Magnetospheric Imaging Instrument(MIMI) Charge Energy Mass Spectrometer (CHEMS) contains a deflection system and an overall field of view of 159 x 4 deg. that is comprised of three distinct energetic particle telescopes each having a field of view of 53 x 4. All telescopes share the same deflection mechanism, but each has its own start and stop microchannel plate (MCP) and its own solid-state detector (SSD). Much of the data returned by CHEMS is separated by telescope. The deflection plate power supply (DPPS) has 32 different voltages that can be applied across the deflection plates. For any single DPPS step, the electrostatic analyzer only transmits incoming ions within a narrow range of energy per charge (a 3% pass band). The CHEMS calibrated data set includes the Pulse Height Analysis (PHA) data collected during the Saturn tour. CHEMS PHA provides a list of individually detected particles, with specific detection parameters for each event, including TOF, energy deposited in the SSD, and telescope number. The energy per charge data for six ion species (H+, He+, H2+, He++, O++, W+) are presented in two forms. (The W+ water ion group includes O+, OH+, H20+ and H30+). One form is a set of tables which are of variable length and use a comma to separate various fields, and the other is a PDF file containing the energy per charge spectrograms and are based on CHEMS PHA data. The original data has been decommutated and decoded by software at the Applied Physics Laboratory (APL) and calibrated and further processed by software at the University of Maryland. This data set should be among the first used by a user of any of the MIMI CHEMS archive as it will lead one to information required to search for more detailed or highly specialized features in the original data.

Access & Use Information

Public: This dataset is intended for public access and use. License: us-pd

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Metadata Created Date January 31, 2023
Metadata Updated Date December 6, 2023
Data Update Frequency irregular

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date January 31, 2023
Metadata Updated Date December 6, 2023
Publisher National Aeronautics and Space Administration
Data First Published 2021-05-21
Data Last Modified 2023-01-26
Category Earth Science
Public Access Level public
Data Update Frequency irregular
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 712d1d52-a394-461b-8376-29335ecd5aa9
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL
Program Code 026:005
Related Documents
Source Datajson Identifier True
Source Hash 921a523790d4a960f00cb3dc115e8ebcf24e8814dc27d9a1e33a838f44acdbb0
Source Schema Version 1.1

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