In this paper we will present characterization of our Microwave Kinetic Inductance Detectors (MKIDs). The design process involved using Sonnet and LEdit 8.3. In this design, we employed a structure consisting of TiN (3nm)/Ti (10nm)/TiN(3nm) layers covered by a 100nm aluminum layer. This structure provides a kinetic inductance of 100 pH/Sqcm and a critical temperature of 1.1 Kelvin. The MKIDs were fabricated on 5-inch silicon wafers with a resistivity exceeding 15000 ohm cm. The designs cover three frequency regimes: 1-2 GHz, 2-4 GHz, and 3-6 GHz. This variation in frequency ranges allows us to study the improvement of quality factors and provides a range of frequencies for testing our electronics.
Modern scientific complementary metal-oxide semiconductor (sCMOS) detectors provide a highly competitive alternative to charge-coupled devices (CCDs), the latter of which have historically been dominant in optical imaging. sCMOS boast comparable performances to CCDs with faster frame rates, lower read noise, and a higher dynamic range. Furthermore, their lower production costs are shifting the industry to abandon CCD support and production in favour of CMOS, making their characterization urgent. In this work, we characterized a variety of high-end commercially available sCMOS detectors to gauge the state of this technology in the context of applications in optical astronomy. We evaluated a range of sCMOS detectors, including larger pixel models such as the Teledyne Prime 95B and the Andor Sona-11, which are similar to CCDs in pixel size and suitable for wide-field astronomy. Additionally, we assessed smaller pixel detectors like the Ximea xiJ and Andor Sona-6, which are better suited for deep-sky imaging. Furthermore, high-sensitivity quantitative sCMOS detectors such as the Hamamatsu Orca-Quest C15550-20UP, capable of resolving individual photoelectrons, were also tested. In-lab testing showed low levels of dark current, read noise, faulty pixels, and fixed pattern noise, as well as linearity levels above 98% across all detectors. The Orca-Quest had particularly low noise levels with a dark current of 0.0067 ± 0.0003 e−/s (at −20◦C with air cooling) and a read noise of 0.37 ± 0.09 e− using its standard readout mode. Our tests revealed that the latest generation of sCMOS detectors excels in optical imaging performance, offering a more accessible alternative to CCDs for future optical astronomy instruments.
KEYWORDS: Radio over Fiber, Reflection, Relative intensity noise, Analog electronics, Radio telescopes, Radio astronomy, Optical transmission, Connectors, Semiconductor lasers, Signal attenuation, Interference (communication)
Optical fibers, known for their immunity to electromagnetic interference, present a promising alternative to coaxial cables for long-range signal transmission in radio telescopes. This study introduces a cost-effective solution for analog signal transmission over fiber, specifically designed for radio astronomy applications. By modifying Small Form-factor Pluggable (SFP) modules, we developed a dual-channel Radio-over-Fiber (RFoF) system with a total cost under $100 USD. Our measurements indicate that the system meets the performance requirements of most radio telescope configurations and has reached technology readiness level 6. This manuscript details the design, modifications, and testing of the SFP modules, showcasing their potential benefits for radio astronomy.
Traditional optical astronomy is limited to the measurement of transient signals at time scales greater than ∼ 1ms due to the readout speed of detectors and read noise limitations to sensitivity in short exposures. The Ultra-Fast Astronomy Project (UFA)1, 2 explores much faster events in the sub-millisecond domain. We designed a single-photon imaging camera based on position-sensitive silicon photomultiplier (PS-SiPM) with a low-cost FPGA readout system to observe such events. The sensor operates in a photon-counting mode with time resolution on the order of 10ns and a spatial resolution of around 200μm. We present our camera’s electronic and mechanical design, the algorithm for data handling, and testing and calibration data.
In our Ultra-Fast Astronomy (UFA) program, we aim to improve measurements of variability of astronomical targets on millisecond and shorter time scales. In this work, we present initial on-sky measurements of the performance of silicon photomultiplier detectors (SiPMs) for UFA. We mounted two different SiPMs at the focal plane of the 0.7-m aperture Nazarbayev University Transient Telescope at the Assy-Turgen Astrophysical Observatory, with no filter in front of the detector. The 3 mm × 3 mm SiPM single-channel detectors have a field of view of 2.2716 ′ × 2.2716 ′ . During the nights of October 28–29, 2019, we measured sky background, bright stars, and an artificial source with a 100-Hz flashing frequency. We compared detected SiPM counts with Gaia satellite G-band flux values to show that our SiPMs have a linear response. With our two SiPMs (models S14520-3050VS and S14160-3050HS), we measured a dark current of ∼130 and ∼85 kilo counts per second (kcps), and a sky background of ∼201 and ∼203 kcps, respectively. We measured an intrinsic crosstalk of 10.34% and 10.52% and derived a 5σ sensitivity of 13.9 and 14 Gaia G-band magnitude for 200-ms exposures, for the two detectors, respectively. For a 10-μs window, and allowing a false alarm rate of once per 100 nights, we derived a sensitivity of 22 detected photons, or six Gaia G-band magnitudes. For nanosecond timescales, our detection is limited by crosstalk to 12 detected photons, which corresponds to a fluence of ∼155 photons per square meter.
We present program objectives and specifications for the first generation Ultra-Fast Astronomy (UFA) observatory which will explore a new astrophysical phase space by characterizing the variability of the optical (320 nm - 650 nm) sky in the millisecond to nanosecond timescales. One of the first objectives of the UFA observatory will be to search for optical counterparts to fast radio bursts (FRB) that can be used to identify the origins of FRB and probe the epoch of reionization and baryonic matter in the interstellar and intergalactic mediums. The UFA camera will consist of two single-photon resolution fast-response detector 16x16 arrays operated in coincidence mounted on the 0.7 meter Nazarbayev University Transient Telescope at the Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) located near Almaty, Kazakhstan. We are currently developing two readout systems that can measure down to the microsecond and nanosecond timescales and characterizing two silicon photomultipliers (SiPM) and one photomultiplier tube (PMT) to compare the detectors for the UFA observatory and astrophysical observations in general.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.