CHARA/SPICA: The six-telescope visible combiner and near-infrared fringe tracker for the CHARA Array

@article{mourard2026charaspica,
  title = {{CHARA/SPICA: The six-telescope visible combiner and near-infrared fringe tracker for the CHARA Array}},
  author = {D Mourard and P Bério and C Bailet and A Caci and J Dejonghe and P Geneslay and S Lagarde and D Lecron and A Meilland and F Morand and N Nardetto and C Pannetier and K Perraut and S Rousseau and D Salabert and N Ebrahimkutty and R.V. Ibañez Bustos and J Jonák and R Ligi and H Nowacki and F Patru and M Vrard and L Bourgés and G Mella and N Anugu and T. Ten Brummelaar and C Farrington and D Gies and J Jones and R Koehler and K Kubiak and C Lanthermann and R Ligon and G Schaefer and N Scott and N Turner and J Monnier and S Kraus and J.B Le Bouquin and T Gardner and M Gutierrez and N Ibrahim and E Aristidi and Y Caujolle and C Giordano and A Ziad},
  journal = {Astron.Astrophys.},
  year = {2026},
  month = sep,
  doi = {10.1051/0004-6361/202660905},
  eprint = {2609.02406},
  archivePrefix = {arXiv},
  url = {https://hal.science/hal-05759077v1},
}

TY  - JOUR
TI  - CHARA/SPICA: The six-telescope visible combiner and near-infrared fringe tracker for the CHARA Array
AU  - D Mourard
AU  - P Bério
AU  - C Bailet
AU  - A Caci
AU  - J Dejonghe
AU  - P Geneslay
AU  - S Lagarde
AU  - D Lecron
AU  - A Meilland
AU  - F Morand
AU  - N Nardetto
AU  - C Pannetier
AU  - K Perraut
AU  - S Rousseau
AU  - D Salabert
AU  - N Ebrahimkutty
AU  - R.V. Ibañez Bustos
AU  - J Jonák
AU  - R Ligi
AU  - H Nowacki
AU  - F Patru
AU  - M Vrard
AU  - L Bourgés
AU  - G Mella
AU  - N Anugu
AU  - T. Ten Brummelaar
AU  - C Farrington
AU  - D Gies
AU  - J Jones
AU  - R Koehler
AU  - K Kubiak
AU  - C Lanthermann
AU  - R Ligon
AU  - G Schaefer
AU  - N Scott
AU  - N Turner
AU  - J Monnier
AU  - S Kraus
AU  - J.B Le Bouquin
AU  - T Gardner
AU  - M Gutierrez
AU  - N Ibrahim
AU  - E Aristidi
AU  - Y Caujolle
AU  - C Giordano
AU  - A Ziad
PY  - 2026
DA  - 2026/09/02
JO  - Astron.Astrophys.
DO  - 10.1051/0004-6361/202660905
UR  - https://hal.science/hal-05759077v1
AB  - The suite called Stellar Parameters and Images with a Cophased Array (SPICA) has two interferometric instruments installed at the focus of the CHARA Array located at Mount Wilson, CA. SPICA is made of SPICA-VIS, a fiber-fed six-beam visible spectrograph with three spectral resolutions, and SPICA-FT, a six-beam near-infrared fringe tracker for the fast stabilization of the fringes. SPICA is opening access to imaging in the visible domain with an unprecedented angular resolution down to 0.2 milliarcseconds. It has been designed around a large survey of fundamental parameters of stars over the Hertzsprung- Russell diagram, aiming at understanding the deviations from the standard empirical relations of stellar physics as a function of activity: limb darkening, multiplicity, rotation, winds, and environments. SPICA makes use of the advanced technologies in electron multiplying detectors in the visible and electron- avalanche photodiode arrays in the near-infrared. It benefits from the newly commissioned adaptive optics on the one-meter telescopes of the array. The modules of the visible instrument, SPICA-VIS, optimize the injection of light into single-mode fibers for spatial filtering before spectral dispersion in the image plane. The fringe tracker, SPICA-FT, performs group-delay and phase-delay tracking for six beams in the H band. SPICA-FT can use an all-in-one or ABCD encoding of the fringe signals. SPICA is operational on sky and is close to reaching the expected performance in low spectral resolution, in particular, for the Interferometric Survey of Stellar Parameters (ISSP). More work is still needed to achieve the ultimate performance in terms of sensitivity and to allow operations with higher spectral resolutions.
ER  -