Very high-resolution spectroscopy for extremely large telescopes using pupil slicing and adaptive optics

Area of Science:

• Astronomy and Astrophysics
• Optical Engineering

Background:

• Extremely Large Telescopes (ELTs) face significant challenges in achieving high-resolution spectroscopy due to seeing limitations.
• Current adaptive optics (AO) systems for ELTs require large, complex deformable mirrors that are not yet technologically feasible for visible wavelengths.

Purpose of the Study:

• To propose a novel adaptive optics technique, Pupil Slicing Adaptive Optics (PSAO), to overcome limitations in high-resolution spectroscopy for ELTs.
• To enable spectrograph resolution that is independent of the telescope diameter.

Main Methods:

• The proposed PSAO technique divides the telescope's pupil into multiple sub-pupils.
• Each sub-pupil is equipped with its own deformable mirror, simplifying the optical requirements.
• Images from these sub-pupils are combined incoherently, achieving a resolution limited by the sub-pupil's diffraction limit.

Main Results:

• PSAO circumvents the need for extremely large, multi-element deformable mirrors.
• This technique allows for spectrograph optics and resolution to be independent of the overall telescope diameter.
• It offers a viable path towards high-resolution spectroscopy with ELTs in the visible spectrum.

Conclusions:

• Pupil Slicing Adaptive Optics (PSAO) presents a practical solution for high-resolution spectroscopy with ELTs.
• This method addresses current technological limitations in AO for large telescopes.
• PSAO facilitates the advancement of astronomical observation capabilities with future ELTs.