An exoplanet mission based on a high-altitude balloon is a next logical step in humanity’s quest to explore Earthlike planets in Earthlike orbits orbiting Sunlike stars. The mission described here is capable of spectrally imaging debris disks and exozodiacal light around a number of stars spanning a range of infrared excesses, stellar types, and ages. The mission is designed to characterize the background near those stars, to study the disks themselves, and to look for planets in those systems. The background light scattered and emitted from the disk is a key uncertainty in the mission design of any exoplanet direct imaging mission, thus, its characterization is critically important for future imaging of exoplanets.
Microwave Kinetic Inductance Detectors, or MKIDs, have proven to be a powerful cryogenic detector technology
due to their sensitivity and the ease with which they can be multiplexed into large arrays. An MKID is an energy
sensor based on a photon-variable superconducting inductance in a lithographed microresonator. It is capable
of functioning as both a photon detector across the electromagnetic spectrum and a particle detector. We have
recently demonstrated the world's first photon-counting, energy-resolving, ultraviolet, optical, and near infrared
MKID focal plane array in the ARCONS camera at the Palomar 200" telescope. Optical Lumped Element (OLE)
MKID arrays have significant advantages over semiconductor detectors such as charge coupled devices (CCDs).
They can count individual photons with essentially no false counts and determine the energy (to a few percent)
and arrival time (to ≈1μs) of every photon, with good quantum efficiency. Initial devices were degraded by
substrate events from photons passing through the Titanium Nitride (TiN) material of the resonator and being
absorbed in the substrate. Recent work has eliminated this issue, with a solution found to be increasing the
thickness of the TiN resonator from 20 to 60 nm.
ARCONS, the Array Camera for Optical to Near-infrared Spectrophotometry, was recently commissioned at the
Coude focus of the 200-inch Hale Telescope at the Palomar Observatory. At the heart of this unique instrument
is a 1024-pixel Microwave Kinetic Inductance Detector (MKID), exploiting the Kinetic Inductance effect to
measure the energy of the incoming photon to better than several percent. The ground-breaking instrument is
lens coupled with a pixel scale of 0.23"/pixel, with each pixel recording the arrival time (< 2 _μsec) and energy of
a photon (~10%) in the optical to near-IR (0.4-1.1 microns) range. The scientific objectives of the instrument
include the rapid follow-up and classi_cation of the transient phenomena