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 carrying out a Humboldt Research Fellowship at Institute for Astrophysics and Geophysics (IAG) in Göttingen.

Previously, I was at a post-doctoral researcher at Leiden Observatory after having completed a fellowship at the Harvard & Smithsonian Center for Astrophysics. 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

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 to study stars. I develop models and analyses for their characterization, and to study their magnetic fields.

⬘ I have relied on near-infrared spectroscopy to derive the properties of M dwarfs. These stars are the most numerous around us, and are key targets to study our local Universe and to search for habitable exoplanets.

⬗ I have developed new models to study magnetic fields in low-mass stars. Their study is essential to understand the processes at the origin of stellar magnetic fields and constrain stellar cycles.

⬙ I have leveraged multi-fiber spectroscopic observations, allowing us to record simultaneous spectra for dozens of stars in young globular clusters to study the properties of Be stars.

Publications | Contributions | Teaching

• New Paper !
  P. I. Cristofari, S. H. Saar, A. A. Vidotto, et al., A fast method for deriving relative small-scale magnetic field variations from high-resolution spectroscopy, 2026, accepted for publication in A&A
• A. K. Dupree, P. I. Cristofari, M. MacLeod, et al., Betelgeuse: Detection of the Expanding Wake of the Companion Star, 2026, ApJ, 998, 50
• S. Bellotti, P. I. Cristofari, J. R. Callingham, et al., A magnetic field study of two fast-rotating, radio-bright M dwarfs: StKM 1-1262 and V374 Peg, 2025, A&A, 704, A298
• 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, A&A, 702, A111
• 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, ApJ, 991, 165
• 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

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
• ORCID

© Picture from Pixabay.

External links

• Full list of publications on NASA ADS
  Public NASA ADS library where I will try to keep a full list of publications (as coresponding author or co-author)


• My PhD manuscript
  The manuscript is written in English, with a foreword, introduction and conclusion in French


• Videos for the "Fil Ballon" with Astrojeunes 2020 [YouTube]
  Because of covid-19, we revisited the format of this annual event and recorded a series of videos to describe the conception of the payload module attached to a stratospheric balloon.

© Picture from Pixabay.

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