Highly Sensitive, Non-cryogenic NIR High-resolution Spectrograph, WINERED

2022 ◽  
Vol 134 (1031) ◽  
pp. 015004
Author(s):  
Yuji Ikeda ◽  
Sohei Kondo ◽  
Shogo Otsubo ◽  
Satoshi Hamano ◽  
Chikako Yasui ◽  
...  
Keyword(s):  
High Resolution ◽  
Near Infrared ◽  
New Technology ◽  
Optical Design ◽  
Wide Band ◽  
Integration Time ◽  
Optical Wavelength ◽  
Custom Made ◽  
Intermediate Size ◽  
Large Telescopes

Abstract WINERED is a novel near-infrared (NIR) high-resolution spectrograph (HRS) that pursues the highest possible sensitivity to realize high-precision spectroscopy in the NIR as in the optical wavelength range. WINERED covers 0.9–1.35 μm (z, Y, and J-bands) with three modes (Wide mode and two Hires modes) at the maximum spectral resolutions of R = 28,000 and R = 70,000. For fulfilling the objective, WINERED is designed with an unprecedentedly high instrument throughput (up to 50% at maximum including the quantum efficiency of the array) that is three times or more than other existing optical/NIR HRSs. This is mainly realized by a combination of non-white pupil and no fiber-fed configuration in optical design, the moderate (optimized) wavelength coverage, and the high-throughput gratings. Another prominent feature of WINERED is “warm” instrument despite for infrared (IR) observations. Such non-cryogenic (no cold stop) IR instrument finally became possible with the combination of custom-made thermal-cut filter of 10−8 class, 1.7 μm cutoff HAWAII-2RG array, and a cold baffle reducing the direct thermal radiation to the IR array into the solid angle of f/2. The thermal background is suppressed below 0.1 photons pixel−1 s−1 even in the wide band of 0.9–1.35 μm under the environment of 290 K. WINERED had been installed to the 3.58 m New Technology Telescope at La Silla Observatory, ESO, since 2017. Even with the intermediate size telescope, WINERED was confirmed to provide a limiting magnitude (for SNR = 30 with 8 hr. integration time) of J = 16.4 mag for the Wide mode and J = 15.1 mag for the Hires mode, respectively, under the natural seeing conditions. These sensitivities are comparable to those for the existing NIR-HRSs attached to the 8–10 m class telescopes with AO. WINERED type spectrographs may become a critical not only for the currently on-going extremely large telescopes to reduce the developing cost and time but also for smaller telescopes to extend their lives with long programs.

scholarly journals New HI Observations of the prototype Polar Ring Galaxy NGC 4650A

1997 ◽  
Vol 14 (1) ◽  
pp. 92-95
Author(s):  
Magda Arnaboldi
Keyword(s):  
High Resolution ◽  
Velocity Field ◽  
Central Region ◽  
Near Infrared ◽  
New Technology ◽  
Host Galaxy ◽  
Polar Structure ◽  
Polar Ring ◽  
Compact Array ◽  
Band Image

AbstractNew, high-resolution observations of the HI emission line and 20 cm continuum at the Australia Telescope Compact Array (ATCA) for the prototype polar ring galaxy NGC 4650A are presented. They show the presence of a far more extended HI distribution than previously observed with the VLA, and a very regular velocity field out to a distance of ∼50 kpc. The combined analysis of the HI data with optical and near-infrared (NIR) images argues against previous warp models used to describe the dynamics of this object. Further analysis of the new B-band image obtained at the European Southern Observatories New Technology Telescope (NTT) indicates clearly that the polar structure extends continuously to within about 200 pc of the nucleus of the central host galaxy, ruling out the presence of a ‘hole’ in the central region of this component. The presence of two spiral arms stretching out in the polar disk seems to represent the most likely explanation for the observed morphology and kinematics.

Optical design of the high-resolution near-infrared spectrograph

2006 ◽  
Author(s):  
Ming Liang ◽  
R. R. Joyce ◽  
S. S. Eikenberry ◽  
K. H. Hinkle ◽  
G. P. Muller ◽  
...  
Keyword(s):  
High Resolution ◽  
Near Infrared ◽  
Optical Design

scholarly journals High-Performance Ultra-Thin Spectrometer Optical Design Based on Coddington’s Equations

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 323
Author(s):  
Zhiwei Feng ◽  
Guo Xia ◽  
Rongsheng Lu ◽  
Xiaobo Cai ◽  
Hao Cui ◽  
...  
Keyword(s):  
High Resolution ◽  
Spectral Resolution ◽  
High Performance ◽  
Optical Design ◽  
Pixel Size ◽  
Simulation Design ◽  
Central Wavelength ◽  
Spot Radius ◽  
Unique Method ◽  
Almost All

A unique method to design a high-throughput and high-resolution ultrathin Czerny–Turner (UTCT) spectrometer is proposed. This paper reveals an infrequent design process of spectrometers based on Coddington’s equations, which will lead us to develop a high-performance spectrometer from scratch. The spectrometer is composed of cylindrical elements except a planar grating. In the simulation design, spot radius is sub-pixel size, which means that almost all of the energy is collected by the detector. The spectral resolution is 0.4 nm at central wavelength and 0.75 nm at edge wavelength when the width of slit is chosen to be 25 μm and the groove density is 900 lines/mm.

scholarly journals Design and Implementation Guidelines for a Modular Spectral-Domain Optical Coherence Tomography Scanner

2018 ◽  
Vol 2018 ◽  
pp. 1-22 ◽  
Author(s):  
Farid Atry ◽  
Israel Jacob De La Rosa ◽  
Kevin R. Rarick ◽  
Ramin Pashaie
Keyword(s):  
Optical Coherence Tomography ◽  
Imaging System ◽  
Optical Design ◽  
Spectral Domain ◽  
Design Parameters ◽  
Optical Coherence ◽  
Custom Made ◽  
Essential Knowledge ◽  
Sd Oct

In the past decades, spectral-domain optical coherence tomography (SD-OCT) has transformed into a widely popular imaging technology which is used in many research and clinical applications. Despite such fast growth in the field, the technology has not been readily accessible to many research laboratories either due to the cost or inflexibility of the commercially available systems or due to the lack of essential knowledge in the field of optics to develop custom-made scanners that suit specific applications. This paper aims to provide a detailed discussion on the design and development process of a typical SD-OCT scanner. The effects of multiple design parameters, for the main optical and optomechanical components, on the overall performance of the imaging system are analyzed and discussions are provided to serve as a guideline for the development of a custom SD-OCT system. While this article can be generalized for different applications, we will demonstrate the design of a SD-OCT system and representative results for in vivo brain imaging. We explain procedures to measure the axial and transversal resolutions and field of view of the system and to understand the discrepancies between the experimental and theoretical values. The specific aim of this piece is to facilitate the process of constructing custom-made SD-OCT scanners for research groups with minimum understanding of concepts in optical design and medical imaging.

Ultrastable high-resolution spectrographs for large telescopes

1998 ◽  
Author(s):  
Francisco Diego ◽  
Ian A. Crawford ◽  
David D. Walker
Keyword(s):  
High Resolution ◽  
Large Telescopes

scholarly journals Genotyping of GATA4 Gene Variant (G296S) in Malaysian Congenital Heart Disease Subjects by Real-Time PCR High Resolution Melting Analysis

2013 ◽  
Vol 32 (2) ◽  
pp. 152-157
Author(s):  
Nora Fawzi ◽  
Ramachandran Vasudevan ◽  
Patimah Ismail ◽  
Mazeni Alwi ◽  
Ahmad Fazli Abdul Aziz ◽  
...  
Keyword(s):  
Congenital Heart Disease ◽  
Heart Disease ◽  
High Resolution ◽  
Congenital Heart ◽  
High Resolution Melting ◽  
New Technology ◽  
Cost Effective ◽  
Study Cohort ◽  
Hrm Analysis ◽  
Melting Analysis

Summary Background: Congenital heart disease (CHD) is the most common birth defect; however, the underlying etiology is unrecognized in the majority of cases. GATA-binding protein 4 (GATA4), a cardiac transcription factor gene, has a crucial role in the cardiogenesis process; hence, a number of heterozygote sequence variations were identified as a cause of CHD. G296S heterozygote variant is the most frequently reported GATA4 gene sequence alteration. This study aims to investigate the role of G296S variant of the GATA4 gene in Malaysian CHD subjects. Methods: We have investigated 86 Malaysian CHD subjects with cardiac septation defects for the presence of the GATA4 gene heterozygote variant (G296S) by the new technology of high resolution melting (HRM) analysis. Results: Genotyping of G296S (c.886G>A) by HRM analysis shows that all the sample genotypes were of the wild GG type genotype and the heterozygote mutant GA genotype was totally absent from this study cohort. Conclusions: The results of our study showed that the G296S variant of the GATA4 gene was not associated with the development of CHD in Malaysian subjects. The use of HRM analysis proved a cost-effective, high-throughput, specific and sensitive genotyping technique which eliminates the need for unnecessary sequencing.

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