Voids@CPPM members¶
Team members¶
Alice Pisani¶
Alice Pisani is a cosmologist with expertise in large-scale structure analysis. She is a full member of the Euclid Consortium and is also involved in the Rubin LSST Dark Energy Science Collaboration (DESC) and in the DESI collaboration. After studying at Sapienza University of Rome, Alice obtained a PhD in Astrophysics from Université Pierre et Marie Curie (now Sorbonne Université). She then spent several years in the United States as a researcher and physics professor, at Princeton University, at the Flatiron Institute's Center for Computational Astrophysics and at the Cooper Union. In 2024, Alice was appointed Research Professor at the CNRS (Directrice de Recherche) and joined CPPM to lead the ERC project COSMOBEST as Principal Investigator. She also holds a Chaire d'Excellence A*MIDEX from Aix-Marseille Université. Alice is a member of the Roman Space Telescope Galaxy Redshift Survey Project Infrastructure Team (GRS PIT) and is involved in the Wide-field Spectroscopic Telescope (WST) and the Subaru Prime Focus Spectrograph (PFS). She built the Voids@CPPM team to work on data from modern surveys. Her goal is to place stringent constraints on the standard cosmological model by studying cosmic voids, the large underdense regions in the galaxy distribution, using data from the latest generation of ground-based and space telescopes.
Pauline Vielzeuf¶
Pauline Vielzeuf is a cosmologist whose research focuses on developing methods for optimal cosmological inference from large galaxy surveys. A central aim of her work is multi-probe analysis: combining galaxy survey data with cosmic microwave background observations from experiments including Planck, ACT, the Simons Observatory and CMB-S4. By bringing these complementary probes together, Pauline seeks to tighten constraints on cosmological models and deepen our understanding of the fundamental properties of the Universe.
Nico Schuster¶
Nico Schuster is a cosmologist who obtained his PhD in physics from Ludwig-Maximilians-Universität (LMU) Munich, Germany. He is now a postdoctoral researcher at CPPM (Fall 2024 – Fall 2027). His research focuses on the unique characteristics of voids compared with other structures in the Universe, their sensitivity to potential new physics, and the role of gravity in their formation, using state-of-the-art simulations. Nico also works on developing voids as cosmological probes of the physical nature of the Universe, its laws and its constituents, using current and upcoming observations from the Dark Energy Spectroscopic Instrument (DESI), the ESA Euclid mission and the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST).
Giulia Degni¶
Giulia Degni is a PostDoc at CPPM in Alice Pisani's group. She is a cosmologist specialising in the data analysis of large-scale surveys exploiting the power of void from a clustering perspective. Her expertise lies in modelling the void–galaxy cross-correlation function to extract cosmological constraints. Her interests involves also velocity reconstructions. She obtained her PhD in Roma Tre University in 2025. She co-leads the void working group in Wide-field Spectroscopic Telescope (WST), and co-leads the paper activities in Euclid. She is also part of DESI and is a member of the Roman Space Telescope Galaxy Redshift Survey Project Infrastructure Team (GRS PIT).
Pierre Boccard¶
Pierre Boccard is a PhD student at CPPM in Alice Pisani's team (expected completion Fall 2027). He joined the COSMOBEST project after earning his Bachelor's and Master's degrees at EPFL. Pierre has expertise in strong gravitational lensing, developed during his Master's thesis at the University of Chicago, as well as experience with cosmological simulations. His PhD research focuses on cosmic voids in Rubin LSST, concentrating on simulations in preparation for the first data release. He also studies cosmic voids in Euclid and DESI.
Katayoon Ghaemi¶
Katayoon Ghaemi is a PhD student (Fall 2024 - Fall 2027) at CPPM in Alice Pisani's team. She completed her Master's degree in Astrophysics and Cosmology at the University of Padua, carrying out her Master's thesis on large-scale structure at the Institute of Cosmos Sciences of the University of Barcelona (ICCUB). She works with spectroscopic data from DESI and Euclid to constrain cosmology with voids, focusing on measuring the void–galaxy cross-correlation function. She is also a member of LSST and WST.
Julien Zoubian¶
Julien Zoubian is a research engineer and permanent staff member at CPPM. He is a full member of the Euclid Consortium, where he serves as NISP Instrument Model Owner (IMO). He is an expert in slitless spectroscopy simulation and initiated the development of TIPS, the NISP sky simulator, now maintained by the Euclid Simulation Organisation Unit (OU-SIM). Julien also has expertise in modelling and machine learning, and in deploying these on computing facilities, from the CPPM GPU platform to national resources such as CC-IN2P3 and the Jean Zay supercomputer. He sits on the scientific committee of the CNRS AstroInfo thematic school and is a member of the ANR DISPERS project.
Marie-Claude Cousinou¶
Marie-Claude Cousinou is a Full Professor at Aix-Marseille Université whose expertise lies in large-scale structure. She is a pioneer in the treatment of spurious voids, work she began while producing void catalogues from BOSS data and now applies to modern surveys. Throughout her career, she has balanced teaching and research, with interests ranging from particle physics to cosmology in the Euclid and DESI projects.
Stéphanie Escoffier Martory¶
Stéphanie Escoffier Martory is a CNRS Research Professor at CPPM and a member of the eBOSS, DESI and Euclid collaborations, three major spectroscopic galaxy surveys. Her goal is to better understand the nature of dark energy, which drives the accelerated expansion of the Universe. Her work focuses on the galaxy distribution and cosmic voids, as well as cross-analyses with the cosmic microwave background and gravitational waves.