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Sergi Hildebrandt Rafels

Photo of Sergi Hildebrandt Rafels


4800 Oak Grove Drive
M/S 169-320

Pasadena, CA 91109





Member of:

Origin of the Universe


  • PhD in Theoretical Physics - University of Barcelona

Professional Experience

  • Jet Propulsion Laboratory, Pasadena, Calif., Research Scientist, Astrophysics Element (2013-Present)
  • California Institute of Technology, Pasadena, Calif. (2011-Present)
    • Visiting Faculty Associate (2014-Present). Lecturer in Physics (2014-Present)
    • Member of the BICEP ARRAY bolometer telescope collaboration, California Institute of Technology (2016-Present)
    • Member of the Bicep2 bolometer telescope collaboration, California Institute of Technology (2011-Present)
    • Member of the Keck array collaboration, California Institute of Technology (2011-Present)
    • Principal Investigator of The Ten MilliArcSecond (TMAS) camera, The Hale Telescope, at Palomar Observatory, California Institute of Technology (2012-Present)
    • Visitor (2013-2014)
    • Senior Research fellow (2011-2012)
  • Senior Research Fellow. Laboratoire Astrophysique et Cosmologie. (2010)
  • Core Team member of the HFI instrument in Planck (2010-2015)
  • Core Team member of the LFI Instrument in Planck (2007-2015)
    • Planck Scientist (2007-2017)
  • Project Scientist of FastCam, European Nothern Observatory (2006-2010)
  • Project Scientist of COSMOSOMAS, 11-19 GHz multiple radiometer. Instituto de Astrofisicade de Canarias (2003-2008)

Research Interests

  • CMB data analysis and cosmology. Polarization and Inflation
  • Direct imaging and characterization of exoplanets from space
  • Global Navigation Systems: real time positioning
  • Visible Adaptive Optics (Palomar)
  • Gravitational physics: Intermediate mass black holes, regularized black holes

Selected Awards

  • JPL Team award (2021). Roman Coronagraph Science Team. For engaging across functional and institutional boundaries to develop creative solutions for CGI observation calibrations.
  • JPL Team Award for the exceptional contribution to the data analysis of Planck 2018 data. (2019)
  • Giuseppe and Vanna Cocconi Prize of the European Physical Society's High Energy Energy and Particle Physics Division for the Planck team. (2019)
  • NASA Group Achievement Award (2019) "for the substantial and effective scientific, technical, and management work in developing the Large Mission Concept Studies for the 2020 Astrophysics Decadal Survey.
  • Voyager Award (2018, individual): For the creation of the first Starshade imaging simulation tool.
  • Gruber Cosmology Prize to the Planck Team. (2018)
  • Royal Academy Group Achievement Award for the Planck Satellite Team. (2018)
  • Group Achievement Award to BICEP2 and Planck Mission Joint Data Analysis Team. (2015)
  • Group Achievement Award to U.S. Planck Data Analysis Team. (2014)
  • Group Achievement Award to BICEP2 Data Analysis Team. (2014)

Selected Publications

  1. BICEP / Keck XVI: Characterizing Dust Polarization Through Correlations with Neutral Hydrogen. BICEP/Keck Collaboration. Accepted for publication in ApJ. 2023.
  2. Nancy Grace Roman Space Telescope Coronagraph Instrument Observation Calibration Plan. R. Zellem et al (including Sergi Hildebrandt)., Roman Coronagraph Public Report,, 2022.
  3. BICEP / Keck XV: The BICEP3 CMB Polarimeter and the First Three Year Data Set. BICEP/Keck Collaboration. Accepted for publication, Phys. Rev. D, 2022.
  4. BICEP / Keck XIV: Improved constraints on axion-like polarization oscillations in the cosmic microwave background. BICEP/Keck Collaboration. Phys. Rev. D. 105, 2, 2022.
  5. BICEP/Keck XIII: Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season. BICEP/Keck Collaboration. Phys. Rev. Letter, 127, 151301, 2021.
  6. S.R. Hildebrandt, S. Shaklan, E. Cady, M. Turnbull, SISTER: Starshade Imaging Software Toolkit fir Exoplanet Reconneisance. J. Astron. Telesc. Instrum. Syst. 7 (2), 021217, 2021.
  7. M. Turnbull, N. Zimmerman, S.R. Hildebrandt et al. A Community Exoplanet Imaging Data Challenge for Roman CGI and Starshade Rendezvous. J. Astron. Telesc. Instrum. Syst. 7 (2), 021218, 2021.
  8. Z. Li, S.R. Hildebrandt et al. Direct Imaging of Exoplanets Beyond the Radial Velocity Limit. AJ, 162, 9, 2021.
  9. Andrew Romero-Wolf, Geoffrey Bryden, Sara Seager, et al. (including S.R. Hildebrandt) (2021), Starshade rendezvous: exoplanet sensitivity and observing strategy. J. Astron. Telesc. Instrum. Syst. 7(2) 021210, 2021.
  10. Eliad Peretz, Kevin Hall, John C. Mather, Stuart Shaklan, Sergi Hildebrandt, Exoplanet imaging performance envelopes for starshade-based missions. J. Astron. Telesc. Instrum. Syst. 7(2), 021215, 2021.
  11. Eliad Peretz, John C. Mather, Lucas Pabarcius, et al. (including S.R. Hildebrandt) Mapping the observable sky for a Remote Occulter working with ground-based telescopes. J. Astron. Telesc. Instrum. Syst. 7(2), 021212, 2021.
  12. Renyu Hu, Sergi R. Hildebrandt, Mario Damiano, et al. Starshade exoplanet data challenge. J. Astron. Telesc. Instrum. Syst. 7(2), 021216, 2021
  13. BICEP2/Keck Array XII: Constraints on axionlike polarization oscillations in the cosmic microwave background. BICEP2/Keck Array collaboration. Phys. Rev. D, 103, 042002, 2021.
  14. Mario Damiano and Renyu Hu and Sergi R. Hildebrandt Multi-orbital-phase and Multiband Characterization of Exoplanetary Atmospheres with Reflected Light Spectra, AJ, 160, 206, 2020,
  15. Planck intermediate results - LVII. Joint Planck LFI and HFI data processing, A&A, 643, A42, 2020
  16. HabEx collaboration: The Habitable Exoplanet Observatory (HabEx) Mission Concept Study Final Report.
  17. BICEP2/Keck Array XI: Beam Characterization and Temperature-to-Polarization Leakage in the BK15 Dataset. ApJ 844, 114, 2019.
  18. Publications with the BICEP/Keck Collaboration:
  19. BK-X: Constraints on Primordial Gravitational Waves Using Planck, WMAP, and New BICEP2/Keck Observations through the 2015 Season. The Keck Array and BICEP2 Collaborations, Phys. Rev. Lett. 121, 221301, 2018.
  20. SISTER Handbook 2019
  21. BK-V: Measurements of B-mode Polarization at Degree Angular Scales and 150 GHz by Keck Array The BICEP2 and Keck Array Collaborations, ApJ 811, 126, 2015.
  22. A Joint Analysis of BICEP2/Keck Array and Planck Data The BICEP2/Keck and Planck Collaborations, Phys. Rev. Lett. 114, 101301, 2015.
  23. BK-IV: Optical Characterization and Performance of the BICEP2 and Keck Array Experiments The BICEP2 and Keck Array Collaborations, ApJ 806, 206, 2015.
  24. Antenna-coupled TES Bolometers used in BICEP2, Keck Array, and SPIDER The BICEP2, Keck Array, and SPIDER Collaborations, 2015.
  25. BICEP2 Collaboration: BICEP2 II: Experiment and Three-Year Data Set. URL BICEP2 Collaboration: BICEP2 I: Detection Of B-mode Polarization at Degree Angular Scale (2014) URL0
  26. Planck Collaboration Papers (over 100 papers with some most cited papers in astrophysics).
  27. Planck 2013 results. XVI. Cosmological parameters. Planck Collaboration (>3,500 cites).
  28. Palm-3000: Exoplanet Adaptive Optics for the 5 m Hale Telescope", Richard Dekany, et al., The Astrophysical Journal, Volume 776, Number 2 (2013).
  29. "Detection of Anomalous Microwave Emission in the Pleiades Reflection Nebula with Wilkinson Microwave Anisotropy Probe and the COSMOSOMAS Experiment." G'enova-Santos, R.; Rebolo, R.; Rubiño-Mart'in, J. A.; L'opez-Caraballo, C. H.; Hildebrandt, S. R. (2011), ApJ 743 67G.
  30. "COSMOSOMAS observations of the cosmic microwave background and Galactic foregrounds at 11 GHz: evidence for anomalous microwave emission at high Galactic latitude" Hildebrandt, S. R.; Rebolo, R.; Rubiño-Martín, J. A.; Watson, R. A.; Gutiérrez, C. M.; Hoyland, R. J.; Battistelli, E. S., (2007), MNRAS 382 594H.
  31. "New type of regular black holes and particlelike solutions from nonlinear electrodynamics", Burinskii, A., Hildebrandt, S.R., Phys. Rev. D 65, 104017 (2002)
  32. "Kerr-Schild and generalized metric motions" Hildebrandt, S. R., Gen. Rel. Grav., vol. 34 (2002) 65118.