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MINERVA-Australis Time Through NN-Explore

Proposing for the Call

The MINERVA Australis team held an information session on September 21, 2022.

Proposals should be submitted to the NN-Explore Program through the NOIRLab proposal process. Information about the current NOIRLab call can be found at the NOIRLab proposal pages.

Background

As part of the NN-EXPLORE program, NASA has entered into a partnership with the MINERVA-Australis consortium. Starting in 2020B, 300 hours of shared-risk observing time per semster with the facility on MINERVA-Australis are available to researchers based at US institutions. MINERVA-Australis is a dedicated exoplanet observatory operated by the University of Southern Queensland (USQ) in Queensland, Australia. The MINERVA-Australis facility is suitable for observation programs requiring precision radial velocities such as individual measurements to constrain orbits and masses, RM-effect, or Doppler tomography, precision photometric observations such as transit observations, and spectroscopic stellar characterization.

The facility is located at USQ's Mt. Kent Observatory, and saw first light in 2018; commissioning of the facility was completed in mid-2019. MINERVA-Australis consists of 4 (0.7m) PlaneWave CDK700 telescopes; these telescopes have two ports, allowing each to be used for either spectroscopic or photometric observations.

The shared risk time can be used to apply for spectroscopic and/or photometric observations. A summary of the facility and its capabilities can be found in the commissioning paper by Addison et al. 2019.

Spectroscopy

The spectroscopic observations cover 480 - 630nm at R>80000 with no order overlap and some small wavelength gaps between the orders. Spectroscopically the telescope array can observe targets with V<11.5 magnitude. Very bright targets (V<8) should be close to the spectrograph noise floor and RV precision better than 5m/s (depending on the project rotational velocity, V sini ). Targets with V>8 will be photon limited in their RV precision (again, this RV precision is reduced by higher stellar projected rotation, V sini ). Indicative precision can be seen in the following examples.

  • Typical Minvera-Australis target: HD 222237, Teff=4700K, V sini=5.2km/s, Vmag=7.0, median uncertainty = 10m/s, tint=20 min (per individual telescope)
  • Typical hotter star: TOI 3460, Teff=6500K, V sini=7km/s, Vmag=9.4, median uncertainty = 18m/s, tint=60 min (per individual telescope)
  • Typical fainter star: TOI 2420, Teff=5700K, V sini=6km/s, Vmag=11.5, median uncertainty = 33m/s, tint=45 min (per individual telescope)

The allocated observations are queue scheduled and data is reduced within a few days of each observation and a summary with preliminary RV results are sent through via email to the requesting astronomer. For spectroscopy, all telescopes available will observe the same target individually for each observation. The individual telescope observations can be combined as independent measurements to produce a more precise result (i.e. all four telescopes combined will provide an uncertainty approximately half the size of that from one telescope). In addition, the project provides a spectroscopic diagnoistic plot for each observation:



Spectroscopic diagnostic plot show the spectrum and model fit with stellar parameter output values, the correlation profile associated with the radial velocity, the derived line profile, and an zoomed in view of the Na-D doublet. Click here to download higher res version.

Photometry

The photometric observations can be requested to use only a specified number of telescopes (e.g. only 1 telescope for a simple ephemeris check on an easy to detect transit, or 4 telescopes on a faint target or small transit). The photometric observations are going through a process of automation at the moment, so requests may be manually or automatically managed. Our testing has shown the best photometric precision with white light observations (i.e. no filter), but full Sloan and some Bessell filters are available. As an example of the capability of our photometric precision we include a plot showing a comparison to LCO 1m observations of TOI824. TOI824 is a V=11.3mag star with a transiting planet of size 2.9 Earth Radii, and a transit depth of 1.5ppt.



Photometric comparison plot showing the transit of TOI824 as observed by LCO in z and B with their 1m telescopes and with Minerve-Australis utilizing two(2) 0.7m telescopes. The diagnostic on the right shows decrease in the point-to-point scatter as a function of binning in minutes. Click here to download higher res version.

The allocated photometric observations will be scheduled, and the photometric data will be reduced within a few days. The requesting astronomer will be provided a summary of the data via email. Similar to spectroscopy, the individual telescope observations can be combined as independent measurements to produce a more precise result.


Restrictions of the Call

NASA has made available to researchers based at US institutions, 300 hours on the Minerva-Australis facility per semester. The time is intended for exoplanet research, primarily of TESS targets but other exoplanet science will be considered. Proposed observing time will be allocated in hours and must include all science and calibration observations necessary to accomplish the science. More information can be requested by contacting David Ciardi at NExScI or Rob Wittenmyer at USQ.

As MINERVA-Australis is a scientific consortium, proposers must abide by the following restrictions:

  • The MINERVA-Australis has listed a set of "Collaboration Targets," which are a set of targets that the collaboration is observing (see LIST HERE ). "Collaboration Targets" can be proposed for observation through the NASA time if the proposal principal investigator forms a collaboration with the appropriate MINERVA-Australis collaboration or the proposer and the MINERVA-Australis collaboration member come to a mutual agreement regarding the proposed observations.
  • Observations will be made, on behalf of the NASA observers, in queue-mode by the MINERVA-Australis team.
  • The MINERVA-Australis team will deliver the proposer's raw data, 1D extracted spectra, and radial velocities (if desired by the proposer).
  • Data obtained for US community observers will be archived at NExScI, through the ExoFOP service. Archived data will have the option to have a maximum 12-month proprietary period or of making the data public with no proprietary period.
  • Any publications arising from the use of NASA time on MINERVA-Australis are subject to the main MINERVA-Australis publication policy regarding the inclusion of the listed Architects and Builders [to be provided by the Collaboration] and should acknowledge the NN-EXPLORE Program [see below].

Acknowledgments for Selected Programs

Publications resulting from data collected as part of the selected programs are requested to include the following acknowledgement:

"Data presented herein were obtained with the MINERVA-Australis facility at the Mt. Kent Observatory from telescope time allocated through the NN-EXPLORE program. NN-EXPLORE is a scientific partnership of the National Aeronautics and Space Administration and the National Science Foundation."

(last updated April 4th, 2023 09:58:08)