This is the case with studies conducted as broad international cooperation. The studies are long, extensive and expensive, and the research consortia comprise hundreds or even thousands of researchers.
In such major projects, typically all members of the study can sign all publications that are produced by the study.
“Setting up the experiment can take 20 years and then another 20 years of experiments are conducted. Everyone does their part, so it is only fair that everyone gets to sign the discoveries,” says Paula Eerola, programme director at the Helsinki Institute of Physics and professor of experimental elementary particle physics.
“Problems arise if citations are used to rank researchers or to determine which topics are most important to an individual researcher’s work.”
For all of her research career, Eerola has participated in the development of equipment for the European Organization for Nuclear Research (CERN), with the result that her name was associated with the discovery of the uncharged Higgs boson in 2012.
Eerola’s own Higgs research, however, has focused on the discovery of the charged Higgs boson – an as-yet undiscovered particle – and her main research topic at CERN has been the bottom quark.
According to Eerola, citation numbers are also misleading in particle physics, as during the period when experiments are being planned, there is often a lengthy dry spell during which the researcher produces no publications. When the experiment finally launches, it may seem that the researcher has suddenly become unprecedentedly productive.
“I’m no better or worse as a researcher now than I was ten years ago, when my experiment was in the planning stage.”
Mika Juvela, university lecturer in observational astronomy, is in a similar situation.
Most of Juvela’s citations come from his participation in the European Space Agency's famous Planck satellite project, particularly the all-sky map of the cosmic microwave background published in 2013.
“After I had been in the consortium for long enough, I was granted Planck scientist status, which means that I can participate in all publications produced by the consortium," Juvela explains.
“I’ve signed most cosmology papers as well as other publications that were close to my own research field, but not all of the consortium’s publications."
Juvela’s core expertise is interstellar dust and how stars are created in interstellar clouds. His favourite publication from the Planck mission is a list of 13,000 cold objects in space which could be in the process of producing a star, a publication relatively unknown to the general public.
Highly cited researchers: physics, chemistry and astronomy