Portal to Los Alamos Opacity Codes


This is your gateway to the set of opacity codes developed at the Los Alamos National Laboratory.

The TOPS code has been developed to calculate multigroup opacities that can be written in a variety of formats for use in radiation transport codes. Arbitrary mixture of any elements for which OPLIB data exist is supported. Opacities of special mixtures that are important in astrophysical applications are also available as a separate option.


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Comments, suggestions and questions are welcome.

Click here to access the TOPS opacity calculation

Click here to access the ASTRO opacity calculation

Click here to go to the T-1 group home page

Click here to access the atomic structure and cross section portal

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