Paul I. Cristofari

Thesis manuscript

Below you will find the PhD manuscript as published in 2022. It can also be downloaded here:

Cool Stars 22 Poster

Here is the poster presented for the Cool Stars conference in 2022:

About me

I am an astrophysicist currently working at Leiden Observatory with Professor A. Vidotto. Previously, I was a post-doctoral fellow at the Harvard & Smithsonian Center for Astrophysics working with Professor A. Dupree. I completed my PhD in 2022 at the Institut de Recherche en Astrophysique et Planétologie, located at the Observatoire Midi Pyrénée (OMP) in Toulouse, France

Before starting my PhD, I obtained a master's degree in fundamental physics from the Aix-Marseille University, with a specialization in particles and astroparticles, and a bachelor's degree in Chemistry from the University Toulon, France.

When I am not doing science, you will find me playing music, reading, fixing my bike or running.

Research

My research leverages the last generation of high-resolution spectrometers and revolves around three main topics: the caracterization of M dwarfs, the study of stellar magnetic fields, and the study of stars in young globular clusters.

⬘ M dwarfs have become central to our understanding of the solar neighborhood and for the characterization of exoplanets: they are the most numerous stars around us, and ideal targets to search for habitable exoplanets.

⬗ Stellar magnetic fields play a crucial role in stellar formation, evolution, and on the habitability of the planets orbiting them. Their study is also essential to understand stellar magnetic cycles analogous to the Solar cycle, in particular for fully convective stars. My work addresses some fundamental questions: are magnetic cycles ubiquitous? What are at the processes at the origin of magnetic fields in fully convetive stars?

⬙ Photometric studies have revealed multiple populations of stars in young globular clusters. With spectroscopic observations of Be stars in these clusters, we try to provide constraints on the mechanism that lead to the population of fast rotating stars and answer the fundamental question: were they born this way or spun up?

Publications | Contributions | Teaching

• New Paper !
  P. I. Cristofari , J.-F. Donati, S. Bellotti, et al., Rotational modulation and long-term evolution of the small-scale magnetic fields of M dwarfs observed with SPIRou, 2025, accepted for publication in A&A
• New Paper !
  P. I. Cristofari , A. K. Dupree, A. P. Milone, et al., Spectroscopic Confirmation: Fast rotators in the young clusters NGC 1856 and NGC 1953, 2025, accepted for publication in ApJ
• P. I. Cristofari , A. K. Dupree, A. P. Milone, et al., Rotation and Hα emission in a young SMC cluster: a spectroscopic view of NGC 330 , 2024, ApJ, 972, 72
• P. I. Cristofari , J. -F. Donati , C. Moutou, et al., Measuring small-scale magnetic fields of 44 M dwarfs from SPIRou spectra with ZeeTurbo, 2023, MNRAS, 526, 5648
• P. I. Cristofari , J. -F. Donati , C. P. Folsom, et al., Constraining atmospheric parameters and surface magnetic fields with ZeeTurbo: an application to SPIRou spectra, 2023, MNRAS, 522, 1342
• P. I. Cristofari , J. -F. Donati , T. Masseron, et al., Estimating the atmospheric properties of 44 M dwarfs from SPIRou spectra, 2022, MNRAS, 516, 3802
• P. I. Cristofari , J. -F. Donati , T. Masseron, et al., Estimating fundamental parameters of nearby M dwarfs from SPIRou spectra, 2022, MNRAS, 511, 1893
• E. Martioli, G. Hébrard, P. Fouqué, et al., TOI-1759 b: a transiting sub-Neptune around a low mass star characterized with SPIRou and TESS, 2022 A&A, 660, A86
• G. P. P. L. Otten, A. Vigan, et al., Direct characterization of young giant exoplanets at high spectral resolution by coupling SPHERE and CRIRES+, 2021, A&A, 646, A150

Publications | Contributions | Teaching

• Bfields conference, Constraining magnetic fields of M dwarfs from high resolution spectra [Talk]
• AAS meeting, A spectroscopic view of NGC 330 [Poster]
• PLATO PSM WP12 meeting, Characterizing atmospheric parameters from high-resolution spectra [Talk]
• ExoSystèmes III, Constraining atmospehric parameters and magnetic fields with ZeeTurbo [Talk]
• International SPIRou Science Meeting, Using ZeeTurbo to constrain magnetic fields and atmospheric parameters from SPIRou spectra [Talk]
• Cool Stars 21 conference, Deriving atmospheric parameters of M dwarfs with SPIRou [poster]
• PhD days 2022, Modeling SPIRou spectra of M dwarfs: status and challenges [Talk + Poster]
• PS2E group meeting 2021, Deriving fundamental parameters of M dwarfs from SPIRou spectra [Talk]
• ExoSystèmes II conference, On the characterization of 12 M dwarfs observed in the context of the SLS [Talk]
• International SPIRou Science Meeting 2021, Advances on the characterization of M dwarfs observed in the context of the SLS [Talk]
• International SPIRou Science Meeting 2020, Telluric line correction and analysis of Gl 699 [Talk]

Publications | Contributions | Teaching

© Picture from Pixabay.

Contact

cristofari@strw.leidenuniv.nl

• Email
• Linkedin
• Twitter
• ORCID

© Picture from Pixabay.

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