Rubin-LSST

Abstract:

We present early results regarding the morphological and structural properties of galaxies seen with the James Webb Space Telescope (JWST) at z > 3 in the Early Release Observations toward the SMACS 0723 cluster field. Using JWST we investigate, for the first time, the optical morphologies of a significant number of z > 3 galaxies with accurate photometric redshifts in this field to determine the form of galaxy structure in the relatively early universe. We use visual morphologies and Morfometryka measures to perform quantitative morphology measurements, both parametric with light profile fitting (Sérsic indices) and nonparametric (concentration, asymmetry, and smoothness (CAS) values). Using these, we measure the relative fraction of disk, spheroidal, and peculiar galaxies at 3 1.5 disk galaxies dominate the overall fraction of morphologies, with a factor of ∼10 relative higher number of disk galaxies than seen by the Hubble Space Telescope at these redshifts. Our visual morphological estimates of galaxies align closely with their locations in CAS parameter space and their Sérsic indices. © 2022. The Author(s). Published by the American Astronomical Society.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu

Abstract:

This paper presents initial testing of the first batch of LGAD sensors fabricated by Teledyne e2v in collaboration with the University of Birmingham, University of Oxford, Rutherford Appleton Laboratory and the Open University. Wafers with different energy and dose of the gain layer implant have been characterised with IV, CV and gain measurements. The same set of measurements were made using PiN diodes fabricated on the same wafer as a reference. Results are in-line with expectations and with LGADs produced at more established vendors. Preliminary results suggests Te2v LGADs have a moderate gain in the order of 10 to 50 before irradiation at operational voltages well below breakdown, as required for optimal timing resolution