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Title: Giga-z: A 100,000 OBJECT SUPERCONDUCTING SPECTROPHOTOMETER FOR LSST FOLLOW-UP

Journal Article · · Astrophysical Journal, Supplement Series
;  [1];  [2];  [3]
  1. Department of Physics, University of California, Santa Barbara, CA 93106 (United States)
  2. Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom)
  3. Department of Astrophysics, California Institute of Technology, 1216 East California Boulevard, Pasadena, CA 91106 (United States)

We simulate the performance of a new type of instrument, a Superconducting Multi-Object Spectrograph (SuperMOS), that uses microwave kinetic inductance detectors (MKIDs). MKIDs, a new detector technology, feature good quantum efficiency in the UVOIR, can count individual photons with microsecond timing accuracy, and, like X-ray calorimeters, determine their energy to several percent. The performance of Giga-z, a SuperMOS designed for wide field imaging follow-up observations, is evaluated using simulated observations of the COSMOS mock catalog with an array of 100,000 R{sub 423{sub nm}} = E/{Delta}E = 30 MKID pixels. We compare our results against a simultaneous simulation of LSST observations. In 3 yr on a dedicated 4 m class telescope, Giga-z could observe Almost-Equal-To 2 billion galaxies, yielding a low-resolution spectral energy distribution spanning 350-1350 nm for each; 1000 times the number measured with any currently proposed LSST spectroscopic follow-up, at a fraction of the cost and time. Giga-z would provide redshifts for galaxies up to z Almost-Equal-To 6 with magnitudes m{sub i} {approx}< 25, with accuracy {sigma}{sub {Delta}z/(1+z)} Almost-Equal-To 0.03 for the whole sample, and {sigma}{sub {Delta}z/(1+z)} Almost-Equal-To 0.007 for a select subset. We also find catastrophic failure rates and biases that are consistently lower than for LSST. The added constraint on dark energy parameters for WL + CMB by Giga-z using the FoMSWG default model is equivalent to multiplying the LSST Fisher matrix by a factor of {alpha} = 1.27 (w{sub p} ), 1.53 (w{sub a} ), or 1.98 ({Delta}{gamma}). This is equivalent to multiplying both the LSST coverage area and the training sets by {alpha} and reducing all systematics by a factor of 1/{radical}({alpha}), advantages that are robust to even more extreme models of intrinsic alignment.

OSTI ID:
22136497
Journal Information:
Astrophysical Journal, Supplement Series, Vol. 208, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0067-0049
Country of Publication:
United States
Language:
English