Efficient scheduling of astronomical observations. Application to the CARMENES radial-velocity survey

Abstract

Targeted spectroscopic exoplanet surveys face the challenge of maximizing their planet detection rates by means of careful planning. The number of possible observation combinations for a large exoplanet survey, i.e., the sequence of observations night after night, both in total time and amount of targets, is enormous. Sophisticated scheduling tools and the improved understanding of the exoplanet population are employed to investigate an efficient and optimal way to plan the execution of observations. This is applied to the CARMENES instrument, which is an optical and infrared high-resolution spectrograph that has started a survey of about 300 M-dwarf stars in search for terrestrial exoplanets. We use evolutionary computation techniques to create an automatic scheduler that minimizes the idle periods of the telescope and that distributes the observations among all the targets using configurable criteria. We simulate the case of the CARMENES survey with a realistic sample of targets, and we estimate the efficiency of the planning tool both in terms of telescope operations and planet detection. Our scheduling simulations produce plans that use about 99$\%$ of the available telescope time (including overheads) and optimally distribute the observations among the different targets. Under such conditions, and using current planet statistics, the optimized plan using this tool should allow the CARMENES survey to discover about 65$\%$ of the planets with radial-velocity semi-amplitudes greater than 1$m{s}^{-1}$ when considering only photon noise. The simulations using our scheduling tool show that it is possible to optimize the survey planning by minimizing idle instrument periods and fulfilling the science objectives in an efficient manner to maximize the scientific return.

18 pages, 8 figures, 6 tables

References in corpus (23)

• The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms
• Las Cumbres Observatory Global Telescope Network
• The false positive rate of Kepler and the occurrence of planets
• Habitable Zones Around Main-Sequence Stars: Dependence on Planetary Mass
• The Occurrence Rate of Small Planets around Small Stars
• The HARPS search for southern extra-solar planets XXXIV. Occurrence, mass distribution and orbital properties of super-Earths and Neptune-mass planets
• A New Planet Around an M Dwarf: Revealing a Correlation Between Exoplanets and Stellar Mass
• Parametrizing the exoplanet eccentricity distribution with the Beta distribution
• Trumpeting M Dwarfs with CONCH-SHELL: a Catalog of Nearby Cool Host-Stars for Habitable ExopLanets and Life
• Planetary detection limits taking into account stellar noise. I. Observational strategies to reduce stellar oscillation and granulation effects
• Detecting Planets Around Very Low Mass Stars with the Radial Velocity Method
• CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOS
• Bayesian search for low-mass planets around nearby M dwarfs. Estimates for occurrence rate based on global detectability statistics
• Planetary detection limits taking into account stellar noise. II. Effect of stellar spot groups on radial-velocities
• The night-sky at the Calar Alto Observatory
• Radial velocity signatures of Zeeman broadening
• The HARPS search for southern extra-solar planets XXXV. Planetary systems and stellar activity of the M dwarfs GJ 3293, GJ 3341, and GJ 3543
• The HARPS search for southern extra-solar planets XXXV. Super-Earths around the M-dwarf neighbors Gl433 and Gl667C
• A Young Planet Search in Visible and IR Light: DN Tau, V836 Tau, and V827 Tau
• The HARPS search for southern extra-solar planets. XXXIV. A planetary system around the nearby M dwarf GJ163, with a super-Earth possibly in the habitable zone
• A multiwavelength radial velocity search for planets around the brown dwarf LP 944-20
• The HADES RV Programme with HARPS-N@TNG II. Data treatment and simulations
• The night-sky at the Calar Alto Observatory II: The sky at the near infrared

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• The CARMENES search for exoplanets around M dwarfs. Three temperate to warm super-Earths
• Radial velocity photon limits for the dwarf stars of spectral classes F--M
• The CARMENES search for exoplanets around M dwarfs. Telluric absorption corrected high S/N optical and near-infrared template spectra of 382 M dwarf stars
• Gliese 12 b: A temperate Earth-sized planet at 12 pc ideal for atmospheric transmission spectroscopy
• The CARMENES search for exoplanets around M dwarfs. A super-Earth planet orbiting HD 79211 (GJ 338 B)
• Deep Learning and LLM-based Methods Applied to Stellar Lightcurve Classification
• $\mathtt{KOBEsim}$: a Bayesian observing strategy algorithm for planet detection in radial velocity blind-search surveys