Historical Content Note: The following material is reprinted from publications from throughout Fermilab's history. It should be read in its original historical context.

Second Colliding Area

In 1978, Fermilab commissioned the Colliding Detector Facility (CDF) group to design a major detector for antiproton-proton collisions at 2 TeV. This collaboration, under the leadership of Alvin Tollestrup and Roy Schwitters, is close to completion of the design of a large solenoid-calorimetric detector to be installed in the B0 interaction region.

The Laboratory is now considering the second area devoted to colliding proton-antiproton beams. The area available is D0, normally assigned to extraction from the Tevatron during fixed-target running. Constraints of both time and funding place serious limitations on the size of the interaction and staging area around D0. For these and other reasons we are interested in user reactions to the following plan. The Laboratory proposes to construct a second area which will have overall dimensions of 7m x 7m centered on the Tevatron beam pipe. The dimension parallel to the pipe will be 10m long. Any detector designed for this region would have to be removed during fixed-target operation and will have the Main Ring vacuum pipe (21 in. above the Tevatron) as an additional obstruction. Removal of the detector could be by rolling sideways and then disassembly to 20-ton units for crane removal to a staging laboratory or by direct disassembly and lift. The outer dimensions of the detector would have to fit comfortably into the interaction hall with space for access all around. Our present understanding of the collider mode indicates a somewhat lower luminosity for D0 than for B0.

The purpose of this note is to stimulate reactions from the user community in order to refine the area drawings. Thus, preliminary input is sought from all interested parties before April 10. This could be in the form of a comment, a letter of intent, or a criticism, constructive or otherwise. These letters would be useful feedback, but would not be treated as proposals. Proposals for a D0 colliding-beam detector will be called for by a date to be set by the PAC. The Laboratory wishes to stress the fact that the small D0 area calls for a modest detector built by a modestly sized group. Stress should be placed on ease of installation, minimum debugging time, and maximum innovation. The effort would be modest enough to be discontinued after one or two runs (or 3 to 4 months) to be replaced by a newer device or (eventually) by an e-p adventure.

Proposers should also consider the virtue of being ready for possible low-luminosity measurements of approximately 2 TeV collisions by the end of 1983.

This area represents a challenge to the community to propose an imaginative detector that is complementary to or competitive with the major detector.