7 research outputs found
Lethal and sublethal effects of dinotefuran and thiamethoxam on the population growth parameters of the green lacewing, Chrysoperla carnea (Neu.: Chrysopidae), under laboratory conditions
The green lacewing, Chrysoperla carnea (Stephens), is a common natural enemy of various agricultural pestsand widely used as a biocontrol agent in integrated pest management (IPM) programs. The lethal and sublethal effects of the insecticides dinotefuran and thiamethoxam on the first instar larvae of C. carnea was assessed in the laboratory conditions at 25 ± 1°C, 60 ± 5% RH and a photoperiod of 16: 8 (L: D). The LC50 values for dinotefuran and thiamethoxam were 19.382 and 9.880 mg ai/l, respectively, that showed the high toxicity of thiamethoxam on the first instar larvae of C. carnea. To assess the sublethal effects, the first instar larvae were treated with the LC30 for dinotefuran and thiamethoxam at 3.532 and 1.692 mg ai/l, respectively. The estimated rm values in the control, dinotefuran and thiamethoxam were 0.185, 0.186 and 0.143 day-1, respectively. Finite rate of increase (λ) in the control, dinotefuran and thiamethoxam were 1.204, 1.204 and 1.154 day-1. Generation time and doubling time values in the control, dinotefuran and thiamethoxam were 30.77, 30.46 and 35.14 as well as 3.73, 3.72 and 4.82 days, respectively. The gross and net reproductive rates in the control, dinotefuran and thiamethoxam were 459.89, 439.08 and 309.42, and also 298.01, 278.45 and 155.03 (female/female/generation), respectively. Dinotefuran caused no significant adverse effects on the population growth parameters of C. carnea. If similar results are obtained for dinotefuran in the field, it might be an insecticide with low toxicity to C. carnea by using the reduced doses of the insecticide in IPM context. Studies under the laboratory conditions can help us to select some insecticides for additional studies under more natural conditions and for application of suitable insecticides along with natural enemies in pest management
Detectors for the James Webb Space Telescope Near-Infrared Spectrograph I: Readout Mode, Noise Model, and Calibration Considerations
We describe how the James Webb Space Telescope (JWST) Near-Infrared
Spectrograph's (NIRSpec's) detectors will be read out, and present a model of
how noise scales with the number of multiple non-destructive reads
sampling-up-the-ramp. We believe that this noise model, which is validated
using real and simulated test data, is applicable to most astronomical
near-infrared instruments. We describe some non-ideal behaviors that have been
observed in engineering grade NIRSpec detectors, and demonstrate that they are
unlikely to affect NIRSpec sensitivity, operations, or calibration. These
include a HAWAII-2RG reset anomaly and random telegraph noise (RTN). Using real
test data, we show that the reset anomaly is: (1) very nearly noiseless and (2)
can be easily calibrated out. Likewise, we show that large-amplitude RTN
affects only a small and fixed population of pixels. It can therefore be
tracked using standard pixel operability maps.Comment: 55 pages, 10 figure
The Infrared Array Camera (IRAC) for the Spitzer Space Telescope
The Infrared Array Camera (IRAC) is one of three focal plane instruments in
the Spitzer Space Telescope. IRAC is a four-channel camera that obtains
simultaneous broad-band images at 3.6, 4.5, 5.8, and 8.0 microns. Two nearly
adjacent 5.2x5.2 arcmin fields of view in the focal plane are viewed by the
four channels in pairs (3.6 and 5.8 microns; 4.5 and 8 microns). All four
detector arrays in the camera are 256x256 pixels in size, with the two shorter
wavelength channels using InSb and the two longer wavelength channels using
Si:As IBC detectors. IRAC is a powerful survey instrument because of its high
sensitivity, large field of view, and four-color imaging. This paper summarizes
the in-flight scientific, technical, and operational performance of IRAC.Comment: 7 pages, 3 figures. Accepted for publication in the ApJS. A higher
resolution version is at http://cfa-www.harvard.edu/irac/publication
JWST Near-Infrared Detectors: Latest Test Results
The James Webb Space Telescope, an infrared-optimized space telescope being developed by NASA for launch in 2013, will utilize cutting-edge detector technology in its investigation of fundamental questions in astrophysics. JWST's near infrared spectrograph, NIRSpec utilizes two 2048 x 2048 HdCdTe arrays with Sidecar ASIC readout electronics developed by Teledyne to provide spectral coverage from 0.6 microns to 5 microns. We present recent test and calibration results for the NIRSpec flight arrays as well as data processing routines for noise reduction and cosmic ray rejection
Detector Arrays for the James Webb Space Telescope Near-Infrared Spectrograph
The James Webb Space Telescope's (JWST) Near Infrared Spectrograph (NIRSpec) incorporates two 5 micron cutoff (lambda(sub co) = 5 microns) 2048x2048 pixel Teledyne HgCdTe HAWAII-2RG sensor chip assemblies. These detector arrays, and the two Teledyne SIDECAR application specific integrated circuits that control them, are operated in space at T approx. 37 K. In this article, we provide a brief introduction to NIRSpec, its detector subsystem (DS), detector readout in the space radiation environment, and present a snapshot of the developmental status of the NIRSpec DS as integration and testing of the engineering test unit begins
Detectors for the James Webb Space Telescope Near-Infrared Spectrograph I: Readout Mode, Noise Model, and Calibration Considerations
We describe how the James Webb Space Telescope (JWST) Near-Infrared Spectrograph's (NIRSpec's) detectors will be read out, and present a model of how noise scales with the number of multiple non-destructive reads sampling-up-the-ramp. We believe that this noise model, which is validated using real and simulated test data, is applicable to most astronomical near-infrared instruments. We describe some non-ideal behaviors that have been observed in engineering grade NIRSpec detectors, and demonstrate that they are unlikely to affect NIRSpec sensitivity, operations, or calibration. These include a HAWAII-2RG reset anomaly and random telegraph noise (RTN). Using real test data, we show that the reset anomaly is: (1) very nearly noiseless and (2) can be easily calibrated out. Likewise, we show that RTN affects only a small and fixed population of pixels. It can therefore be tracked using standard pixel operability maps
James Webb Space Telescope Near-Infrared Spectrograph: Dark Performance of the First Flight Candidate Detector Arrays
The James Webb Space Telescope (JWST) Near Infrared Spectrograph (NIRSpec) incorporates two 5 micron cutoff (lambda(sub co) = 5 micron) 2048x2048 pixel Teledyne HgCdTe HAWAII-2RG sensor chip assemblies. These detector arrays, and the two Teledyne SIDECAR application specific integrated circuits that control them, are operated in space at T approx. 37 K. This article focuses on the measured performance of the first flight-candidate, and near-flight candidate, detector arrays. These are the first flight-packaged detector arrays that meet NIRSpec's challenging 6 e(-) rms total noise requirement