Atomic Masses, Q-values, and Threshold Energies

The program QCALC has been produced by the National Nuclear Data Center of the Brookhaven National Laboratory, Upton, NY, USA, with funding from the U.S. Department of Energy.
The accompanying data base was produced by the Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, Orsay Campus, France and the National Institute of Nuclear Physics and High-Energy Physics, Amsterdam, The Netherlands.

Neither the BNL nor the USDOE nor the CSNSM nor the NIKHEF-K make any warranty or assume any legal responsibility for the contents of the data base or the results of the program.

Quality LevelExplanation of Terms

• Authoritative: All information in the resource has been verified by authorities as indicated.
• Quality-checked: All information in the resource has been quality-checked as indicated.
• Not quality-checked: Although the information in the resource may come from peer-reviewed journals or other high-quality sources, it has not undergone subsequent quality checking before incorporation in the resource.

: Quality-checked by the IAEA Secretariat
CompletenessExplanation of Terms

• Comprehensive:The resource includes all items in the category for which the resource was created.
• Selective: The resource includes only selected items in the category for which the resource was created, with the process or basis for the selection as indicated.

: Comprehensive
Update FrequencyExplanation of Terms

• Updated continually: A conscientious effort is made to add new information immediately and keep the resource up-to-date on a day-by-day basis.
• Updated periodically: The resource is updated on a schedule. Common values are monthly, quarterly, annually or biennially, but others are also used.
• Updated occasionally: The resource is updated now and then, but not on a schedule.
• Static: The resource is a one-off creation with no plans for updates, or a resource that was updated in the past but has now been frozen with no new input planned.

: Static