EXFOR Formats Description for Users
(EXFOR Basics)

edited by Otto Schwerer *,
IAEA Nuclear Data Section, Vienna, Austria
on behalf of the Nuclear Reaction Data Centres Network
IAEA-NDS-206, June 2008 (pdf version)

Abstract: EXFOR is the exchange format for the transmission of experimental nuclear reaction data between national and international nuclear data centres for the benefit of nuclear data users in all countries. This report contains a general introduction to EXFOR, a detailed description of the exchange format, a brief description of the computational format C4, and tables of the dictionaries of most important abbreviations used in EXFOR.

Table of Contents

(in new window)
  1. A Quick Guide to EXFOR
  2. Overview of the EXFOR Exchange Format
  3. User Output Formats
  4. Appendix: Tables of Dictionaries


EXFOR is the database for experimental nuclear reaction data maintained by the international Network of Nuclear Reaction Data Centres (NRDC) co-ordinated by the IAEA Nuclear Data Section. This manual describes the main principles of the database and the most important features of the EXFOR exchange format of interest to database users. A description of the computational format C4 and brief examples of other output formats are also included.

This manual is not intended as a complete guide to the EXFOR system. NRDC staff and other experts involved in database input (compilation) and/or related software development should consult the following relevant manuals:

Name Report code Topics Intended readership
EXFOR Exchange Formats Manual IAEA-NDS-207 Description of EXFOR exchange formats Compilers, software developers
LEXFOR IAEA-NDS-208 Quantity definitions and compilation guidelines Compilers
EXFOR/CINDA Dictionary Manual IAEA-NDS-213 Description of dictionary formats Compilers, software developers
NRDC Protocol INDC(NDS)-401 Procedures for EXFOR exchange between NRDC centres Compilers, centre heads
NRDC Network document INDC(NDS)-401 Scope of activities and cooperation of NRDC centres Centre heads

How to use this manual

Chapter I (A Quick Guide to EXFOR) explains the basic ideas of EXFOR; it can also be used as a stand-alone introduction which may be sufficient as a guide for the occasional user.

Chapter II gives a detailed overview of the exchange format, containing all details which may be important for users, but excluding technical details which are of significance only for data centre staff and external EXFOR compilers.

Chapter III describes the computational format C4 in some detail and also shows several examples of other user output formats.

The appendix lists the most important codes (abbreviations) from the EXFOR dictionaries which users may need to interpret EXFOR retrievals.


This manual is partly based on earlier work by former NRDC staff. In particular the contributions of V. McLane (National Nuclear Data Center, Brookhaven National Laboratory, USA) and H.D. Lemmel (IAEA Nuclear Data Section, Vienna, Austria) to earlier versions of this manual and other documents related to EXFOR are gratefully acknowledged.

O.S., June 2008

* Minor reivisions by N.Otsuka (IAEA-NDS): Editorial correction for creation the html version (November 2008); Minor correction for "Special conventions" of Computational Format C4 (September 2010); Update of links to manuals (June 2010); Update of data centre list (October 2014).

Citation guideline: When quoting EXFOR data in a publication this should be done in the following way:

"A.B. Author et al.: Data file EXFOR-12345.002 dated 1980-04-05, compare J. Nucl. Phys. 12,345, (1979). EXFOR data retrieved from the IAEA Nuclear Data Section, Vienna."