3rd prize of the Buchalter Cosmology Prize to Dr. Franciolini

The work “Footprints of the QCD Crossover on Cosmological Gravitational Waves at Pulsar Timing Arrays”, by Dr. Gabriele Franciolini and his collaborators Dr. Davide Racco and Dr. Fabrizio Rompineve, has been awarded with the third prize of the Buchalter Cosmology Prize. Dr. Franciolini completed this work while he was an ERC-funded Postdoctoral Fellow at Sapienza.


Pulsar Timing Arrays have recently reported evidence for a gravitational wave (GW) background, and the pending question is whether the signal originates from mergers of supermassive black holes or the early Universe. This paper provides a distinctive signature of the GW background sourced by a wide class of primordial phenomena: the low-frequency tail of the spectrum is modified by the occurrence of QCD confinement. The inclusion of these Standard Model effects has an important impact on model comparison in latest PTA datasets.


The winners of the 2023 Buchalter Cosmology Prize were announced on 11th January at the 243rd meeting of the American Astronomical Society in New Orleans, Louisiana. This annual prize, created by Dr. Ari Buchalter in 2014, seeks to reward new ideas or discoveries that have the potential to produce a breakthrough advance in our understanding of the origin, structure, and evolution of the Universe.


The work by Dr. Franciolini and collaborators has been recognized by the judging panel for “providing an interesting and timely test for a potential early universe contribution to the stochastic background of gravitational waves, arising from features imprinted by the QCD phase transition that could be detected by pulsar timing arrays.”



Gabriele Franciolini, Davide Racco, Fabrizio Rompineve





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