Archives of AR and ISR Divisions - Archives of ISR Committee (ISRC)

Identity Statement [Top]

Reference code(s)



Archives of Accelerator Research Division, AR
Archives of Intersecting Storage Rings Division and committee, ISR and ISRC


1961 - 1983

Level of description


Extent of the unit of description

371 boxes, 906 items, 41 linear metres

Context [Top]

Name of creator

CERN. Accelerator Research, AR Division
CERN. Intersecting Storage Rings, ISR Division

Administrative history

AR Division
The Accelerator Research group was established in December 1956, as part of the PS (Proton Synchrotron) Division, in order to undertake research on the design of future machines. It remained quite small until the end of 1959, when the PS entered into operation, after which more resources were transferred to this area. At first only a small number of members were CERN staff, but this changed in 1958. In 1961 the AR group became the AR division, which existed until 1966.

ISR Division
On 1st January 1967 the groups in AR Division were transferred to the Intersecting Storage Rings Division in the Department ISR Construction.

Proposals for new accelerators at CERN were under consideration from the late 1950s (see AR group above), with the main contenders being Intersecting Storage Rings (ISR) for the existing PS and construction of a new larger synchrotron. A new study group on accelerators, ECFA (European Committee for Future Accelerators), was set up at CERN following meetings in December 1962. In 1963 a Working Party of ECFA, comprising nine people, was set up under the chairmanship of Eduardo Amaldi. In its report the group recommended the construction of both the ISR and the 300 GeV proton synchrotron. In December 1965 the CERN Council approved the ISR project and continued study of the 300 GeV project (which was finally approved, as the SPS (Super Proton Synchrotron) in 1971).

In September 1965 France signed an agreement to provide about forty hectares of land, adjacent to the CERN site located on the Swiss border, for the construction of the ISR. In January 1966 the ISR Division was created and work started on ISR construction. In January 1969 the ISR Committee was set up and twelve experiments were accepted during this year. The ISR was inaugurated on 16 October 1971 and closed on 26 June 1984. The ISR division existed until 1983, when most of its staff moved to the new LEP division.

Immediate source of acquisition or transfer

Collections were received from the following people:
Keith Potter, 1985 Roger Calder, July 1993
Kjell Johnsen, Director of the ISR Department from 1966 to 1975, August 1993
Richard Keyser, November 1993

Content & Structure [Top]

Scope and content

The collection contains reports, correspondence, handbooks and official documents concerning the AR Group, the AR Division and the ISR Division.

The Intersecting Storage Rings at CERN provided head-on collisions between protons in two counter-rotating beams. Protons supplied by CERN's Proton Synchrotron were injected clockwise into one of the rings and counterclockwise into the other, where they could be maintained in a stable orbit for many hours. The two identical rings, 300m in diameter, were interlaced and intersected at 8 points where the proton beams collided head on, with an impact equivalent to that made with a normal type of accelerator of a much higher energy. For example, two 26-GeV colliding beams correspond to a 1500-GeV beam hitting a stationary target, because no recoil energy is wasted. When the ISR began to operate on 27 January 1971, with two proton beams of energy up to 27 GeV each, it was the only proton storage ring machine in the world.

In 1973 the first important discoveries from the experiments at the ISR showed that protons grow in size as their energy is increased; and particles emerging at wide angles revealed scattering between the constituent particles deep inside the protons.

In order to transfer so many particles from the synchrotron and stack them in tight bunches, many technological challenges had to be overcome. New high vacuum techniques had to be developed and new methods for controlling particle beams mastered. The knowledge and expertise gained were helpful to CERN in its subsequent colliding beam projects. In particular, the invention of 'stochastic cooling' by Simon van der Meer (which was successfully tested in the ISR in 1965) enabled unruly beams to be tightly controlled. In 1979 CERN capitalized on its ISR investment by deciding to convert its new SPS proton synchrotron into the world's first proton-antiproton collider. Van der Meer's beam cooling scheme was the key to its success.

Appraisal, destruction and scheduling information

All items have been kept in order in which they were received. Nothing was destroyed


Further accruals may be received.

System of arrangement

Accelerator Research (AR) Group

1 Administration and General CERN-ARCH-AR-1-1-001 to 1-5-010
2 Reports and notes CERN-ARCH-AR-2-001 to 2-003
3 AR/SG (Study Group) CERN-ARCH-AR-3-1-001 to 3-5-031
4 Internal reports CERN-ARCH-AR-4-1-001 to 4-1-004


Intersecting Storage Rings (ISR) Division


Administration and general

01. Group leader meetings
02. Financial
03. Personnel
04. Correspondence
05. ISR Direction
06. Administrative Committee
07. Public relation
08. Reports and publications
09. Conferences
10. ISRU meetings
11. European Accelerator Group
12. ECFA


CERN-ARCH-ISR-01-01-001 to 017
CERN-ARCH-ISR-01-02-001 to 014
CERN-ARCH-ISR-01-03-001 to 034
CERN-ARCH-ISR-01-04-001 to 004
CERN-ARCH-ISR-01-05-001 to 040
CERN-ARCH-ISR-01-06-001 to 022
CERN-ARCH-ISR-01-08-001 to 006
CERN-ARCH-ISR-01-09-001 to 007
CERN-ARCH-ISR-01-10-001 to 004
CERN-ARCH-ISR-01-11-001 to 005
CERN-ARCH-ISR-01-12-001 to 010

02 ISR Projects CERN-ARCH-ISR-02-001 to 005
03 Long term development CERN-ARCH-ISR-03-1-001 to 03-3-001
04 ISR Experiments CERN-ARCH-ISR-04-1-001 to 04-7-002
05 TT2 CERN-ARCH-ISR-05-1-001 to 05-3-001
06 Committees CERN-ARCH-ISR-06-1-001 to 06-8-003
07 ISR Running-in + performance CERN-ARCH-ISR-07-01-001 to 07-15-001
08 MOC (Machine Operation Committee) CERN-ARCH-ISR-08-1-001 to 08-4-001
09 BEIC (Beam Equipment Interaction Committee) CERN-ARCH-ISR-09-1-001 to 09-3-001
10 ISR Drawings CERN-ARCH-ISR-10-1-001
11 ISR Decommissioning CERN-ARCH-ISR-11-1-001 to 11-2-001

ISR-Experimental Support Group (ES)

01. Administration and general
02. ES Committee
03. ES Section
04. Experiments
05. Vacuum Machine
06. Survey
07. Radiation damage
08. SCISR (Superconducting conversion of the ISR)
09. ISR - TH discussions
10. ISR Working party
11. MOC (Machine Operation Committee)
12. Experiments and drawings
13. RF Technical and Internal notes


CERN-ARCH-ISR-12-01-001 to 028
CERN-ARCH-ISR-12-02-001 to 011
CERN-ARCH-ISR-12-03-001 to 020
CERN-ARCH-ISR-12-04-001 to 020
CERN-ARCH-ISR-12-05-001 to 002
CERN-ARCH-ISR-12-06-001 to 002
CERN-ARCH-ISR-12-07-001 to 002
CERN-ARCH-ISR-12-09-001 to 002
CERN-ARCH-ISR-12-10-001 to 003
CERN-ARCH-ISR-12-12-001 to 007



ISR-Computer Group (CO)

01. General
02. General documentation
03. Hardware Descriptions
04. System software
05. Beam Transfer Software
06. Main Ring Software
08. Logbooks


CERN-ARCH-ISR-13-01-001 to 008
CERN-ARCH-ISR-13-02-001 to 008
CERN-ARCH-ISR-13-03-001 to 020
CERN-ARCH-ISR-13-04-001 to 007
CERN-ARCH-ISR-13-05-001 to 007
CERN-ARCH-ISR-13-06-001 to 020
CERN-ARCH-ISR-13-07-001 to 004
CERN-ARCH-ISR-13-08-001 to 002


ISR-Control Room

01. Performance reports
02. Physics Run Data
03. Picture files
04. Index and index ISRC
05. Computer programs
06. Miscellaneous
07. ISR Logbooks


CERN-ARCH-ISR-14-01-001 to 002
CERN-ARCH-ISR-14-03-001 to 008
CERN-ARCH-ISR-14-04-001 to 013
CERN-ARCH-ISR-14-05-001 to 005
CERN-ARCH-ISR-14-06-001 to 053
CERN-ARCH-ISR-14-07-001 to 047


ISR-Control Room

  • Divisional reports from 1966 to 1983


CERN-ARCH-ISR-15-001 to 023


ISR-Control Room

  • Slides and photos construction of the ISR


CERN-ARCH-ISR-16-001 to 007



  • Workshop documents 14-21/09/1977



18 ISR First test slected collection of historical pictures CERN-ARCH-ISR-18-001 to 004
19 Montague's correspondence in connection with the Veksler connective accelerator CERN-ARCH-ISR-19-001 


Intersecting Storage Rings Committee (ISRC)

01 ISRC Documents CERN-ARCH-ISRC-1-01-001 to 006
02 ISRC Documents: working files CERN-ARCH-ISRC-1-02-001 to 009
03 Meetings: minutes CERN-ARCH-ISRC-1-03-001 to 005
04 Meetings: notes CERN-ARCH-ISRC-1-04-001 to 002
05 ISRC Correspondence CERN-ARCH-ISRC-1-05-001 to 013
06 ISRC General documents CERN-ARCH-ISRC-1-06-001 to 006
07 Proposals CERN-ARCH-ISRC-1-07-001 to 006
08 Technical specifications CERN-ARCH-ISRC-1-08-001
09 ISR experiments by intersection CERN-ARCH-ISRC-1-09-001 to 006
10 ISR experiments by year and by number CERN-ARCH-ISRC-1-10-001 to 069

Conditions of access and use [Top]

Conditions governing access

See file level description and the CERN operational circular No 3: rules applicable to archival material and archiving at CERN. In general, records on any subject that are over 30 years old, and all records of a purely scientific nature, may be consulted.

Conditions governing reproduction

Copyright is retained by CERN, no reproduction without permission.

Language / scripts of material

Most of the material is written in English and French.

Finding aids

Listed to file level in the CERN Archives Database.

Description control [Top]

Archivist's note

Description prepared by Maryse Moskofian.

Date(s) of description

Geneva, the 7 January 2002, Revised 2007.