Physics PhD student in Berkeley, working with Pr. U. Seljak. My areas of research revolve around spectroscopic experiments and the connections to weak lensing. I have experience in spectrometric and photometric redshift inference, as well as machine learning techniques (UMAP, SOM, Contrastive learning, data augmentation). I also am interested in primordial He measurements. I like to develop games and stories, cook, play video games and listening to music ! I am currently the co-founder of Overthought games, a 3-person game studio aiming to commercially release a metroidvania game !
Jean Choppin de Janvry
PhD student at Berkeley
Profile
Who am I ?
GitHub
Repositories
Research
Papers
2025 · Submitted to arXiv
Cosmic Shear constraints from HSC Year 3 with clustering calibration of the tomographic redshift distributions from DESI
A reanalysis of HSC Year 3 shear data using new DESI-based clustering-redshift calibration. The updated redshift priors lift the central S8 value toward the Planck result while tightening the uncertainty substantially.
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2025 · Submitted to arXiv
Full calibration of the tomographic redshift distribution from the HSC PDR3 Shape Catalog with DESI
This paper performs a full DESI-based clustering-redshift calibration of all four HSC weak-lensing tomographic bins, including the high-redshift sources that previous calibrations could not fully constrain.
Read abstract2025 · Accepted by ApJ
The SPHEREx Satellite Mission
The mission overview paper describes SPHEREx as the first all-sky near-infrared spectral survey, detailing the instrument, mission design, public data products, and the science cases driving the survey strategy.
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Co-founder
Overthought Games
Independent game studio working on a 2D pixel-art metroidvania.
Open
Projects
Rockets
Mechanical integration, recovery, and telemetry support
PheniCS
PheniCS is a one-year student-led supersonic rocket project that broke Mach 1 at the 2023 C'Space competition. The work combined parachute deployment, mechanical integration, and telemetry software for a record-setting flight campaign.
Open
Mechanical integration, recovery, and avionics support
Sirius
Sirius is a 3.3 m two-stage student rocket program built around pneumatic stage separation. The project combined mechanical design, deployment architecture, and avionics integration for a technically ambitious multi-stage flight.
Open
Project member working on slingshot design and prototyping
KTP
Experimental rocket aiming to deploy a controlled glider through a longitudinal slingshot at the rocket's apogee point.
Open
Projects
Websites
Projects
Other
Co-builder and maintainer
Homemade metal foundry
Student-built aluminum foundry for small casting projects.
Open
Co-founder and early propulsion program lead
HyMir
HyMir is a student-led hybrid rocket engine project supported by the EM2C laboratory. The program focused on building propulsion competence inside the club and structuring a credible experimental engine effort.
Open