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You can use the search function as a "guest" without logging in. All data that TCIA returns without being logged in is public. As a guest, you can add data to the data basket. For more information, see Working with the Data Basket.
If you are not logged into the application, some functions are unavailable; these are saving a search query, viewing saved queries, viewing query histories, and managing saved queries. You also cannot download more than 3 gigabytes of data at one time.
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