Tree rings in Large Synoptic Survey Telescope production sensors: its dependence on radius, wavelength, and back bias voltage

Journal Article · 08 January 2020 · Journal of Astronomical Telescopes, Instruments, and Systems

DOI: https://doi.org/10.1117/1.jatis.6.1.011005 · OSTI ID:1762763

Park, Hye Yun ^[1]; Karpov, Sergey ^[2]; Nomerotski, Andrei ^[3]; Tsybychev, Dmitri ^[4]

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1. Stony Brook Univ., NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
2. Czech Academy of Sciences, Praha (Czech Republic)
3. Brookhaven National Lab. (BNL), Upton, NY (United States)
4. Stony Brook Univ., NY (United States)

Tree rings are one of the sensor effects that may affect precise measurements in the Large Synoptic Survey Telescope (LSST). The effect is caused by silicon wafer manufacturing process, resulting in formation of circular patterns due to variations of the silicon dopant concentration. In this work, we have analyzed flat-field images taken at Brookhaven National Laboratory and SLAC for all production sensors used to build the LSST camera in order to measure the amplitudes and periods of the tree ring patterns as a function of the radius, illumination wavelength, and sensor back bias voltage. With nominal back bias voltage settings, the tree ring amplitudes and periods for both ITL and e2v sensors are considered to have small impact on the galaxy shear measurement in LSST.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: Czech Ministry of Education, Youth, and Sports; European Structural and Investment Fund; USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: SC0012704
• OSTI ID: 1762763
• Report Number(s): BNL--220816-2021-JAAM
• Journal Information: Journal of Astronomical Telescopes, Instruments, and Systems, Journal Name: Journal of Astronomical Telescopes, Instruments, and Systems Journal Issue: 01 Vol. 6; ISSN 2329-4124
• Publisher: SPIECopyright Statement
• Country of Publication: United States
• Language: English