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Title: STRONG LENS TIME DELAY CHALLENGE. I. EXPERIMENTAL DESIGN

The time delays between point-like images in gravitational lens systems can be used to measure cosmological parameters. The number of lenses with measured time delays is growing rapidly; the upcoming Large Synoptic Survey Telescope (LSST) will monitor ∼10{sup 3} strongly lensed quasars. In an effort to assess the present capabilities of the community, to accurately measure the time delays, and to provide input to dedicated monitoring campaigns and future LSST cosmology feasibility studies, we have invited the community to take part in a ''Time Delay Challenge'' (TDC). The challenge is organized as a set of ''ladders'', each containing a group of simulated data sets to be analyzed blindly by participating teams. Each rung on a ladder consists of a set of realistic mock observed lensed quasar light curves, with the rungs' data sets increasing in complexity and realism. The initial challenge described here has two ladders, TDC0 and TDC1. TDC0 has a small number of data sets, and is designed to be used as a practice set by the participating teams. The (non-mandatory) deadline for completion of TDC0 was the TDC1 launch date, 2013 December 1. The TDC1 deadline was 2014 July 1. Here we give an overview of themore » challenge, we introduce a set of metrics that will be used to quantify the goodness of fit, efficiency, precision, and accuracy of the algorithms, and we present the results of TDC0. Thirteen teams participated in TDC0 using 47 different methods. Seven of those teams qualified for TDC1, which is described in the companion paper.« less
Authors:
 [1] ; ;  [2] ; ;  [3] ;  [4] ;  [5] ;  [6]
  1. Kavli Institute for Theoretical Physics, University of California Santa Barbara, Santa Barbara, CA 93106 (United States)
  2. Department of Physics, University of California, 1 Shields Avenue, Davis, CA 95616 (United States)
  3. Department of Physics, University of California, Santa Barbara, CA 93106 (United States)
  4. Kavli Institute for Particle Astrophysics and Cosmology, P.O. Box 20450, MS29, Stanford, CA 94309 (United States)
  5. Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, B.C. V6T 1Z1 (Canada)
  6. Lawrence Berkeley National Laboratory and University of California, Berkeley, CA 94720 (United States)
Publication Date:
OSTI Identifier:
22364373
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 799; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; COMPUTERIZED SIMULATION; COSMOLOGY; DATA ANALYSIS; DIAGRAMS; GRAVITATIONAL LENSES; IMAGES; METRICS; QUASARS; TELESCOPES; TIME DELAY; VISIBLE RADIATION