The DEdicated MONitor of EXotransits and Transients (DEMONEXT): System Overview and Year One Results from a Low-Cost Robotic Telescope for Follow-Up of Exoplanetary Transits and Transients

Abstract

We report on the design and first year of operations of the DEdicated MONitor of EXotransits and Transients (DEMONEXT). DEMONEXT is a 20 inch (0.5-m) robotic telescope using a PlaneWave CDK20 telescope on a Mathis instruments MI-750/1000 fork mount. DEMONEXT is equipped with a $2048\times 2048$ pixel Finger Lakes Instruments (FLI) detector, a 10-position filter wheel with an electronic focuser and $B$, $V$, $R$, $I$, $g^{\prime }$, $r^{\prime }$, $i^{\prime }$, $z^{\prime }$, and clear filters. DEMONEXT operates in a continuous observing mode and achieves 2-4 mmag raw, unbinned, precision on bright $V<13$ targets with 20-120 second exposures, and 1 mmag precision achieved by binning on 5-6 minute timescales. DEMONEXT maintains sub-pixel ($<0.5$ pixels) target position stability on the CCD over 8 hours in good observing conditions, with degraded performance in poor weather ($<1$ pixel). DEMONEXT achieves 1-10% photometry on single-epoch targets with $V<17$ in 5 minute exposures, with detection thresholds of $V\approx 21$. The DEMONEXT automated software has produced 143 planetary candidate transit light curves for the KELT collaboration, and 48 supernovae and transient light curves for the ASAS-SN supernovae group in the first year of operation. DEMONEXT has also observed for a number of ancillary science projects including Galactic microlensing, active galactic nuclei, stellar variability, and stellar rotation.

References in corpus (17)

• The Transiting Exoplanet Survey Satellite
• The Man Behind the Curtain: X-rays Drive the UV through NIR Variability in the 2013 AGN Outburst in NGC 2617
• Las Cumbres Observatory Global Telescope Network
• Temperate Earth-sized planets transiting a nearby ultracool dwarf star
• The Transiting Exoplanet Survey Satellite: Simulations of planet detections and astrophysical false positives
• Design Considerations for a Ground-based Transit Search for Habitable Planets Orbiting M dwarfs
• The Kilodegree Extremely Little Telescope (KELT): A Small Robotic Telescope for Large-Area Synoptic Surveys
• KELT-1b: A Strongly Irradiated, Highly Inflated, Short Period, 27 Jupiter-mass Companion Transiting a mid-F Star
• Improved angular momentum evolution model for solar-like stars II. Exploring the mass dependence
• MOA-cam3: a wide-field mosaic CCD camera for a gravitational microlensing survey in New Zealand
• The KELT-South Telescope
• KELT-20b: A giant planet with a period of P~ 3.5 days transiting the V~ 7.6 early A star HD 185603
• Miniature Exoplanet Radial Velocity Array (MINERVA) I. Design, Commissioning, and First Science Results
• Time-Series Photometry of Stars in and around the Lagoon Nebula. I. Rotation Periods of 290 Low-Mass Pre-Main-Sequence Stars in NGC 6530
• WASP-167b/KELT-13b: Joint discovery of a hot Jupiter transiting a rapidly-rotating F1V star
• KELT-10b: The First Transiting Exoplanet from the KELT-South Survey -- A Hot Sub-Jupiter Transiting a V = 10.7 Early G-Star
• Pushing the Limits of Ground-Based Photometric Precision -- Sub-Millimagnitude Time-Series Photometry of the Open Cluster NGC 6791

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• On the Ca-strong 1991bg-like type Ia supernova 2016hnk: evidence for a Chandrasekhar-mass explosion
• SN 2016coi (ASASSN-16fp): an energetic H-stripped core-collapse supernova from a massive stellar progenitor with large mass loss
• Full orbital solution for the binary system in the northern Galactic disc microlensing event Gaia16aye
• Kojima-1Lb Is a Mildly Cold Neptune around the Brightest Microlensing Host Star
• Revisiting the HIP41378 system with K2 and Spitzer
• EPIC 246851721 b: A Tropical Jupiter Transiting a Rapidly Rotating Star in a Well-Aligned Orbit
• TESS Shines Light on the Origin of the Ambiguous Nuclear Transient ASASSN-18el
• K2 Optical Emission from OJ 287 and Other Gamma-Ray Blazars on Hours-to-Weeks Timescales from 2014-2018