235 research outputs found
The design and characterization of a 300 channel, optimized full-band millimeter filterbank for science with SuperSpec
SuperSpec is an integrated, on-chip spectrometer for millimeter and sub-millimeter astronomy. We report the approach, design optimization, and partial characterization of a 300 channel filterbank covering the 185 to 315 GHz frequency band that targets a resolving power R ~ 310, and fits on a 3.5Ă5.5 cm chip. SuperSpec uses a lens and broadband antenna to couple radiation into a niobium microstrip that feeds a bank of niobium microstrip half-wave resonators for frequency selectivity. Each half-wave resonator is coupled to the inductor of a titanium nitride lumped-element kinetic inductance detector (LEKID) that detects the incident radiation. The device was designed for use in a demonstration instrument at the Large Millimeter Telescope (LMT)
The incidence of human papillomavirus infection following treatment for cervical neoplasia: A systematic review
To systematically review the published literature in order to estimate the incidence and describe the variability of human papillomavirus (HPV) infection in women following treatment for cervical neoplasia
Full-Array Noise Performance of Deployment-Grade SuperSpec mm-Wave On-Chip Spectrometers
SuperSpec is an on-chip filter bank spectrometer designed for wideband moderate-resolution spectroscopy at millimeter wavelengths, employing TiN kinetic inductance detectors. SuperSpec technology will enable large-format spectroscopic integral field units suitable for high-redshift line intensity mapping and multi-object spectrographs. In previous results, we have demonstrated noise performance in individual detectors suitable for photon noise-limited ground-based observations at excellent mm-wave sites. In these proceedings, we present the noise performance of a full RâŒ275 spectrometer measured using deployment-ready RF hardware and software. We report typical noise equivalent powers through the full device of âŒ3Ă10â»ÂčⶠW Hz^(â1/2) at expected sky loadings, which are photon noise dominated. Based on these results, we plan to deploy a six-spectrometer demonstration instrument to the Large Millimeter Telescope in early 2020
SuperSpec: On-chip spectrometer design, characterization, and performance
SuperSpec is an integrated, on-chip spectrometer for millimeter and sub-millimeter astronomy. SuperSpec is demonstrating a proof-of-principle multi-beam spectrometer on the sky at the Large Millimeter Telescope (LMT) in Mexico covering the 200 - 300 GHz frequency range with moderate resolution (R ~ 270 - 290). The dual-polarization, three-pixel instrument will consist of 6 SuperSpec spectrometer chips. We present the design and characterization of the devices being used in the first SuperSpec demonstration along with lab testing of the instrument performance
Low Noise Titanium Nitride KIDs for SuperSpec: A Millimeter-Wave On-Chip Spectrometer
SuperSpec is a novel on-chip spectrometer we are developing for multi-object, moderate resolution (R= 100â500), large bandwidth (âŒ1.65:1), submillimeter and millimeter survey spectroscopy of high-redshift galaxies. The spectrometer employs a filter bank architecture, and consists of a series of half-wave resonators formed by lithographically-patterned superconducting transmission lines. The signal power admitted by each resonator is detected by a lumped element titanium nitride (TiN) kinetic inductance detector operating at 100â200 MHz. We have tested a new prototype device that achieves the targeted R=100R=100 resolving power, and has better detector sensitivity and optical efficiency than previous devices. We employ a new method for measuring photon noise using both coherent and thermal sources of radiation to cleanly separate the contributions of shot and wave noise. We report an upper limit to the detector NEP of 1.4Ă10^(â17) W Hz^(â1/2), within 10 % of the photon noise-limited NEP for a ground-based R=100R=100 spectrometer
SuperSpec: development towards a full-scale filter bank
SuperSpec is a new spectrometer-on-a-chip technology for submm/mm-wave spectroscopy. SuperSpec stands out from other direct-detection submm spectrometer technologies in that the detectors are coupled to a series of resonant filters along a single microwave feedline instead of using dispersive optics. SuperSpec makes use of kinetic inductance detectors (KIDs) to detect radiation in this filter bank. The small profile of this design makes SuperSpec a natural choice to produce a multi-object spectrometer for tomographic mapping or galaxy redshift surveys. We have recently fabricated a device that is a 50 channel subset of a full 280 channel filter bank, which would cover the 190 - 310 GHz range at R = 275. Analysis of the data from this device informs us of the potential design modifications to enable a high-yield background-limited SuperSpec spectrometer. The results indicate that this subset filter bank can scale up to a full filter bank with only a few collisions in readout space and less than 20% variation in responsivity for the detectors. Additionally, the characterization of this and other prototype devices suggests that the noise performance is limited by generation-recombination noise. Finally, we find that the detectors are sufficiently sensitive for ground-based spectroscopy at R = 100, appropriate for tomographic mapping experiments. Further modifications are required to reach the background limit for R = 400, ideal for spectroscopy of individual galaxies
Placing the library at the heart of plagiarism prevention: The University of Bradford experience.
yesPlagiarism is a vexed issue for Higher Education, affecting student transition, retention and attainment. This paper reports on two initiatives from the University of Bradford library aimed at reducing student plagiarism. The first initiative is an intensive course for students who have contravened plagiarism regulations. The second course introduces new students to the concepts surrounding plagiarism with the aim to prevent plagiarism breaches. Since the Plagiarism Avoidance for New Students course was introduced there has been a significant drop in students referred to the disciplinary programme. This paper discusses the background to both courses and the challenges of implementation
The design and characterization of a 300 channel, optimized full-band millimeter filterbank for science with SuperSpec
SuperSpec is an integrated, on-chip spectrometer for millimeter and sub-millimeter astronomy. We report the approach, design optimization, and partial characterization of a 300 channel filterbank covering the 185 to 315 GHz frequency band that targets a resolving power R ~ 310, and fits on a 3.5Ă5.5 cm chip. SuperSpec uses a lens and broadband antenna to couple radiation into a niobium microstrip that feeds a bank of niobium microstrip half-wave resonators for frequency selectivity. Each half-wave resonator is coupled to the inductor of a titanium nitride lumped-element kinetic inductance detector (LEKID) that detects the incident radiation. The device was designed for use in a demonstration instrument at the Large Millimeter Telescope (LMT)
Full-array noise performance of deployment-grade SuperSpec mm-wave on-chip spectrometers
SuperSpec is an on-chip filter bank spectrometer designed for wideband moderate-resolution spectroscopy at millimeter wavelengths, employing TiN kinetic inductance detectors. SuperSpec technology will enable large-format spectroscopic integral field units suitable for high-redshift line intensity mapping and multi-object spectrographs. In previous results, we have demonstrated noise performance in individual detectors suitable for photon noise-limited ground-based observations at excellent mm-wave sites. In these proceedings, we present the noise performance of a full
RâŒ275
RâŒ275
spectrometer measured using deployment-ready RF hardware and software. We report typical noise equivalent powers through the full device of
âŒ3Ă
10
â16
âŒ3Ă10â16
W Hz
â1/2
W Hzâ1/2
at expected sky loadings, which are photon noise dominated. Based on these results, we plan to deploy a six-spectrometer demonstration instrument to the Large Millimeter Telescope in early 2020
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