Program: GN-2024B-Q-314

We propose using MAROON-X to measure the masses of the four transiting temperate Jupiters, two in the TOI-4600 system and two in the TOI-1847 (NGTS-11) system. Gas giants with an equilibrium temperature between 200 and 600 K are important objects bridging hot Jupiters and our own Jupiter. However, they are relatively poorly understood as a population or via individual atmospheric characterizations, and there are very few systems amenable for or already scheduled for JWST observations. TOI-4600 and TOI-1847 are among the handful of systems with two transiting temperate Jupiters that might be suitable for JWST observations. Masses are important for assessing the feasibility of JWST transmission spectroscopic observations, as well as for supporting precise and accurate atmospheric modeling. MAROON-X on Gemini-N is the best instrument to pursue these systems, thanks to its high radial velocity precision coupled with the large aperture. TOI-4600c will have a transit window observable in JWST Cycle 4, but none in Cycle 5, making this a timely and synergistic program with JWST.