United States participation in the Large Hadron Collider (LHC) program has focused Congressional attention on this major European activity, and the impact of such participation on domestic high-energy and nuclear physics research. The LHC is the next-generation proton accelerator that is being built at CERN, the European Laboratory for Particle Physics, in Geneva Switzerland. Prior to committing funds for the LHC, the House Appropriations Committee and the House Science Committee requested the Department of Energy and the National Science Foundation to provide information covering several areas of concern. The enclosed report provides a coordinated response from both agencies to specific questions raised by the various Committees. It also includes information on the Department's management of the U.S. LHC effort in view of the importance of this precedent setting collaboration as well as the need to serve as careful stewards of Federal resources.

The report concludes that U.S. involvement in the LHC will provide the best strategy for maintaining the excellence of the US high-energy physics program, and will have long-term benefits for the country. United States scientists and engineers cannot stay at the cutting edge of accelerator and detector technology -- which impacts many fields of science, not just particle physics -- unless they are involved in the Large Hadron Collider. Such involvement is also necessary to properly train the next generation of US physicists and can help pave the way for even larger scientific collaborations in the future.

A Report to the Congress:

Joint Participation by

the U.S. Department of Energy

and

The National Science Foundation

in the

Large Hadron Collider (LHC)

Program

Table of Contents

I. Introduction

II. CERN and the Large Hadron Collider (LHC) Project

1

2

III. The DOE/NSF Agreement with CERN on the LHC Project

3

IV. Response to the Congressional Request.....

V. Conclusion

Appendices

13

1. CERN Member States' Annual Contributions for 1996...
2. Background Information on CERN......

16

17

3. The DOE/NSF-CERN Agreement and Protocols
4. Contributions to ATLAS and CMS

6. Letter, CERN to DOE and NSF

7. U.S. Participation in Major Experiments at CERN: 1994 data

20

49

51

53

57

8. CERN's 1996 Estimate of the LHC Project Cost

9. Letter from Physics Today, August 1997.

58

60

10. August 8, 1997 letter by HEPAP chairman

63

I. INTRODUCTION

House Appropriations Report 105-190, dated July 21, 1997 stated:

No funds appropriated in this bill for high energy physics may be used for the Large Hadron Collider project unless the Secretary of Energy, in consultation with the Director of the National Science Foundation, has transmitted to the House and Senate Committees on Appropriations, the Committee on Science of the House of Representatives, and the Committee on Energy and Natural Resources of the Senate, a report containing:

(1) assurances that the project will provide for equal access for United
States participants and a significant management role for the United States;
(2) a list of other sources of non-United States funds used for the

project;
(3) an enumeration of the total costs of the project and potential
sources of contingency funding if the project runs over budget;
(4) a statement that the Member States of CERN-

(A) have agreed that future large accelerators and other scientific facilities are expected to be constructed, operated, and supported multinationally and may be located in any participating nation, including the United States;

(B) have agreed that the United States contribution to the construction of the Large Hadron Collider project represents an important step forward in international scientific collaboration; and

(C) will follow the United States' example in high energy physics accelerator construction with interregional contributions to future important scientific construction projects of mutual interest to the United States and the member states of CERN; and

(5) an assessment of the impact of the obligation of United States funds for the project on high energy and nuclear physics projects in the United States.

The April 1997 report of the House Science Committee on the National Science Foundation Authorization Act of 1997 stated:

The Committee is specifically concerned over the potential impacts on U.S. high energy and nuclear physics facilities of proposed U.S. funding for the Large Hadron Collider project at CERN. As a result, the Committee has not authorized any funds in FY 99 in the Major Research Equipment account for construction of the proposed ATLAS and CMS detectors until the Director, in consultation with the Secretary of Energy, has provided a report to the Committee on such impacts.