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

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

Identity Statement | Context | Content and Structure | Conditions of access and use | Description control | Database |

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 and 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: CERN-ARCH-AR

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


Intersecting Storage Rings (ISR) Division: CERN-ARCH-ISR

A - Administration and General
  Group Leaders meetings

01-01-001 to 01-01-017


01-02-001 to 01-02-014


01-03-001 to 01-03-034


01-04-001 to 01-04-004

  ISR Direction

01-05-001 to 01-05-040

  Administrative Committee

01-06-001 to 01-06-022

  Public relation


  Reports and publications

01-08-001 to 01-08-006


01-09-001 to 01-09-007

  ISRU meetings

01-10-001 to 01-10-004


01-12-001 to 01-12-010

B - ISR projects 02-001 to 02-005
C - Long term development 03-1-001 to 03-3-001
D - ISR Experiments 04-1-001 to 04-6
E - TT2 05-1-001 to 05-3-001
F - Committees 06-1-001 to 06-8-003
G - ISR Running-in + performance 07-01-001 to 07-15-001
H - MOC (Machine Operation Committee) 08-1-001 to 08-4-001
I - BEIC (Beam Equipment Interaction Committee) 09-1-001 to 09-3-001
J - ISR Drawings 10-1-001
K - ISR Decommissioning 11-1-001 to 11-2-001


Intersecting Storage Rings (ISR) - Experimental Support Group (ES)

A - Administration and general 12-01-001 to 12-01-028
B - ES Committee 12-02-001 to 12-02-011
C - ES Section 12-03-001 to 12-03-020
D - Experiments 12-04-001 to 12-04-020
E - Vacuum Machine 12-05-001 to 12-05-002
F - Survey 12-06-001 to 12-06-002
G - Radiation damage 12-07-001 to 12-07-002
H - SCISR (Superconducting conversion of the ISR) 12-08-001
I - ISR - TH discussions 12-09-001 to 12-09-002
J - ISR Working party 12-10-001 to 12-10-003
K - MOC (Machine Operation Committee) - ES 12-11-001
L - Experiments and drawings 12-12-001 to 12-12-007


Intersecting Storage Rings (ISR) - Computer Group (CO)



A - General 13-1-001 to 13-1-008
B - General documentation 13-2-001 to 13-2-008
C - Hardware Descriptions 13-3-001 to 13-3-020
D - System software 13-4-001 to 13-4-007
E - Beam Transfer Software 13-5-001 to 13-5-007
F - Main Ring Software 13-6-001 to 13-6-020
G - Miscellaneous 13-7-001 to 13-7-004
H - Logbooks 13-8-001 to 13-8-002


Intersecting Storage Rings (ISR) - Control Room

A - Performance reports 14-1-001 to 14-1-002
B - Physics Run Data 14-2-001
C - Picture files 14-3-001 to 14-3-008
D - Index and index SRC 14-4-001 to 14-4-013
E - Computer programs 14-5-001 to 14-5-005
F - Miscellaneous 14-6-001 to 14-6-053
G - ISR Logbooks 14-7-001 to 14-7-047
H - Divisional reports from 1966 to 1983 15-001 to 15-023
I - Slides and photos construction of the ISR 16-001 to 16-007


Intersecting Storage Rings (ISR) - Workshop

A - Workshop documents 14-21/09/77 17-001


Intersecting Storage Rings Committee (ISRC): CERN-ARCH-ISRC

A - ISRC Documents 1-01-001 to 1-01-006
B - ISRC Documents: working files 1-02-001 to 1-02-009
C - Meetings: minutes 1-03-001 to 1-03-005
D - Meetings: notes 1-04-001 to 1-04-002
E - ISRC Correspondence 1-05-001 to 1-05-013
F - ISRC General documents 1-06-001 to 1-06-006
G - Proposals 1-07-001 to 1-07-006
H - Technical specifications 1-08-001
I - ISR experiments by intersection 1-09-001 to 1-09-006
J - ISR experiments by year and by number 1-10-001 to 1-10-069

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

The ISR collection is being listed to item level in the CERN Archive Database.

Description control [Top]

Archivist's note

Description prepared by Maryse Moskofian

Date(s) of description: Geneva, the 7 January 2002, Revised 2007

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