A group of prominent scientists, including five Nobel Prize winners, wants the ``super collider'' built as originally envisioned even though the cost of the giant particle accelerator could rise by more than $1 billion. The Energy Department's High Energy Physics Advisory Panel agreed Friday with a subcommittee's findings that significantly reducing the size or power of the collider to contain costs would ``unacceptably increase the risk of missing important new physics.'' The panel said it was told that keeping the Texas project as originally envisioned, however, could increase the $5.9 billion pricetag by 20 percent to 30 percent. As designed, the super collider will smash beams of protons into each other in a 53-mile circular tunnel at 20 times the energy possible with the most powerful existing accelerators. It would take a reduction of beam energy of 25 percent to hold costs to the original figure, the advisory panel's report said. But it said the project's mission to learn more about ``such issues as the origin of mass,'' the best efforts of theoretical physicists indicate the original energy ``is about the minimum energy needed to have confidence that these phenomena, in whatever form they may take, will be seen.'' A 25 percent reduction in beam energy means ``broad agreement that this confidence would be lost,'' the report said. A decision on collider spending recommendations is expected from Energy Secretary James Watkins later this month, officials said. The collider is expected to be completed by 1998. Congress last year approved $225 million to begin initial construction and President Bush is expected to request about $393 million for the next fiscal year. The department is reviewing cost estimates by SSC Laboratory in DeSoto, Texas, on how various design changes would affect the price. Officials of the SSC Lab, which contracted to build the accelerator at a site south of Dallas, recommend an increase of about $1 billion to keep the project essentially as it was envisioned in 1986. Sen. Phil Gramm, R-Texas, said he believes a compromise would be reached but would not speculate on the new cost estimate. ``It's important that we try not to build a Cadillac,'' Gramm said. ``We don't have the money, and to attempt to do that would put us in a position where we would have no machine at all.'' The subpanel said the cost increases would give new ammunition to Capitol Hill opponents of the giant machine, which if completed will be the largest, most complicated scientific instrument ever built. Congressional opponents of the collider fear it will draw resources from other scientific projects that would deliver more immediate payouts benefitting the nation's economy and international competitive position. The additional costs would have to be absorbed by U.S. taxpayers or could come from foreign sources. While some members of Congress favor letting foreign sources provide in-kind equipment and services, others fear those countries would gain immediate technological benefits for their industries, at U.S. expense. James F. Decker, acting director of the department's office of energy research, said the collider should ``provide a substantial new physics capability when it comes on line. ``The United States should not spend this large amount of money for a facility that would be only marginally better than some other existing facility,'' Decker said.