JEDI Mission Concept:

JEDI is a 2m aperture space telescope capable of simultaneous wide-field imaging and multiple object spectroscopy with a field of view of 1 square degree. Supernova spectroscopy is the ``bottle-neck'' for obtaining a large number of type Ia supernova (SN Ia) events usable for cosmology; slits are needed to obtain sufficient signal-to-noise for SN Ia spectra. JEDI has the unique ability of simultaneously obtaining slit spectra for all objects in the wide field of view.

The JEDI focal plane is centered by an imaging array consisting of five strips of NIR imaging detectors, covering the wavelength range of 0.8-4.2 microns. The spectrograph fields are adjacent to the imaging fields, allowing simultaneously imaging and spectroscopy in adjacent fields. The wavelength coverage of the spectrograph fields is 1-2 or 0.8-3.2 microns.

JEDI uses the microshutter arrays (already developed for the JWST) as the programmable spectroscopic multi-slit mask, and HAWAII-2 2048x2048 HgCdTe detectors from Rockwell. JEDI will have an Earth-trailing or L2 orbit, with sunshields to achieve passive cooling.

JEDI science goals will be achieved through the JEDI Deep (mission year 1) and the JEDI Wide (mission years 2 & 3) campaigns, both with simultaneous imaging and spectroscopy in adjacent fields. JEDI Deep will cover 4-12 square degrees, while JEDI Wide will cover 1000-10,000 square degrees.