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Documentation and Links  

Welcome to OLTARIS, the On- Line Tool for the Assessment of Radiation in Space. OLTARIS is an integrated tool set utilizing HZETRN (High Charge and Energy Transport). These tools are intended to help scientists and engineers study the effects of space radiation on shielding materials, electronics, and biological systems. This site is intended for users knowledgeable about space radiation and shielding concepts. A users guide and some reference documentation can be found under the Documentation and Links page linked above.

Newest Features


There are no charges associated with the use of OLTARIS, but users must register and get approval from the site administrators before accessing the site contents. New users should click the Sign up link above and complete the OLTARIS Sign Up page. After registration is complete, one of the site administrators will activate your account when approved, and confirmation will be sent to the supplied email address.

System Requirements

OLTARIS requires a standard browser with JavaScript.

Current Capabilities

This is an evolving tool set; new capabilities can and will be added. Please contact the site administrator with comments and suggestions.

Known Issues

The OLTARIS development team is always in the process of making improvements and additions to the site. If you encounter an issue you feel is a bug in the product, please let us know about it. You can use the links which are posted at the top of each page or those here: Report a Bug / Send a Comment for reporting bugs and submitting comments. The OLTARIS development team appreciates your feedback!

Here is a list of known issues:

  1. Help documents and user guides may not be up to date. If it doesn't agree with what's on the page, it probably just needs to be updated. Please let us know.
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