In 1955 the Track Chamber Group (TC) was attached to the Scientific and Technical Services Division (STS) directed by Dr L. Kowarski.

In 1958 Track Chamber Group moved to the Proton Synchrotron Division, PS.

In 1961 TC Hydrogen Bubble Chamber Group (PS-BC-H) became Track Chambers Division (TC) and was directed by Charles Peyrou. Its mandate included :

• design, construction and operation of hydrogen bubble chambers
• prepare jointly with outside laboratories the experimental programme for hydrogen bubble chambers
• analyse the photographs jointly with Data Handling Division (DD)

In 1966 new Departments were formed by regrouping the existing Divisions; these departments existed until 1976. TC remained a Division and was integrated into the Physics II Department.

In 1969 the Nuclear Physics Apparatus (NPA) Division, directed by C. Ramm and responsibie for Heavy Liquid Bubble Chambers, disappeared, and TC Division became the division responsible for the high energy physics program at the PS by means of bubble chambers (Hydrogen Bubble Chambers + Heavy Liquid Bubble Chamber).

In 1976, the departmental structure ceased. With the advent of the large bubble chambers, expert groups of designers and costructors grew-up. Finally, the distinction between those people who design, build and operate the big detectors and those who use them for research was recognized by the setting-up of two new CERN Divisions :

• Experimental Physics Facilities Division (EF) formed from parts of the former Nuclear Physics (NP) and Track Chamber (TC) Divisions
• Experimental Physics Division (EP)