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Ming Liang

Publications and source records attributed to Ming Liang.

2 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2022

The NEID Port Adapter at WIYN: On-Sky Fast Guiding Performance

NEID (NN-explore Exoplanet Investigations with Doppler spectroscopy) is an optical, fiber-fed spectrometer installed on the WIYN 3.5m Telescope. The radial velocity precision that NEID is expected to reach requires the stellar jitter (i.e., the slight irregular movement of the stellar image induced by atmospheric turbulence, wind-shake, etc.) to be controlled within 0.05 arc-seconds 90% of the time in nominal observing conditions (i.e., 0.8-arcsecond seeing and mild winds). To achieve that, the NEID Port Adapter incorporates a fast, first-order wavefront correction system, which implements an Electron-Multiplying CCD camera and a tip/tilt piezo stage to capture and stabilize the stellar image. Here, we use on-sky data to demonstrate the performance of this system under various observing conditions.

Dan Li↗
NASA NTRS2022

The NEID Port Adapter on-Sky Performance

Here we detail the on-sky performance of the NEID Port Adapter one year into full science operation at the WIYN 3.5m Telescope at Kitt Peak National Observatory. NEID is an optical (380-930 nm), fiber-fed, precision Doppler radial velocity system developed as part of the NASA-NSF Exoplanet Observational Research (NN-EXPLORE) partnership. The NEID Port Adapter mounts directly to a bent-Cassegrain port on the WIYN Telescope and is responsible for precisely and stably placing target light on the science fibers. Precision acquisition and guiding is a critical component of such extreme precision spectrographs. In this work, we describe key on-sky performance results compared to initial design requirements and error budgets. While the current Port Adapter performance is more than sufficient for the NEID system to achieve and indeed exceed its formal instrumental radial velocity precision requirements, we continue to characterize and further optimize its performance and efficiency. This enables us to obtain better NEID datasets and in some cases, improve the performance of key terms in the error budget needed for future extreme precision spectrographs with the goal of observing ExoEarths, requiring ∼ 10 cm/s radial velocity measurements.

Sarah E. Logsdon↗