Authors or signatories?

Over recent years, the traditional author list has been joined by a new kid on the block: a signatory list, used by projects ranging from TESLA to SuperB, and soon to be joined by CLIC. What’s the difference?


Next week, the Conceptual Design Report (CDR) for CLIC Physics and Detectors will be published, and it will be fronted by a signatory list of over 1000 people. A volume describing the CLIC accelerator will follow soon after. CLIC, the Compact Linear Collider, is an international study for a possible future particle physics research facility, and one of several options on the table for the post-LHC era. Keeping future options open has been part of the normal run of things since particle-physics-time-immemorial: several technologies are studied and developed in parallel so that when the physics results from operating facilities point the way forward, the community can choose the best option for the physics, and for the available resources.

“Long-term R&D is essential in particle physics,” explains Steinar Stapnes, Linear Collider Study Leader at CERN, “and the CLIC project is part of a broad global effort to develop options for the future. These include energy upgrades to the LHC and a superconducting linear collider as well as CLIC. We believe very strongly that having these options available as real implementation possibilities is very important.”

Like many formal documents, a Conceptual Design Report is usually authored and signed by a group of people. But it’s not always obvious who should be on the author list. Sometimes formal collaborations prepare the various types of design reports. This was the case, for example, with the LHC experiments. But for TESLA, SuperB and now CLIC Physics and Detectors, there’s no formal collaboration structure, which makes the author list less obvious. Furthermore, the work has been carried out over a long timescale, and sometimes jointly with other projects worldwide that have common technical challenges, making it virtually impossible to define an up-to-date and representative author list.

The solution adopted by the TESLA linear collider study, spearheaded by DESY, was to invite anyone who supports the project to sign, and this is the approach that the CLIC study has adopted for its Physics and Detectors CDR, a document drawn from a very diverse range of sources and building on the work of scientists from all over the world over a period of decades. The process was initiated for the CLIC CDR in September 2011 and presented at the Linear Collider workshop in Grenada last October. Signing it shows support for CLIC as one of a range of possible options for the future of particle physics.

The approach is not without difficulties, however. Responsibilities are harder to identify, major contributions must be also published elsewhere to ensure recognition, and it’s important to avoid the perception that signatory lists equate to competition between projects.

“Signatory lists should only be used when other options are not well suited, as in the case of very long-term, global projects that overlap with others,” explains Lucie Linssen, leader of CERN's Linear Collider Detector project. “Signing up should be seen as an inclusive action, and doesn’t exclude support for other options as well. It’s a vote for developing options for pursuing the high-energy frontier.”

by James Gillies