Near Infrared Instrumentation for 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.

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Adaptive Optics: Performance and Limitations

Symposium - International Astronomical Union ◽

10.1017/s0074180900107727 ◽

1994 ◽

Vol 158 ◽

pp. 273-281

Author(s):

Francois Roddier

Keyword(s):

Adaptive Optics ◽

Near Infrared ◽

Image Improvement ◽

Large Telescopes

Adaptive optics systems are now being developed for astronomical applications. On large telescopes, a substantial image improvement can be obtained in the near infrared, using natural guide stars.

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Faint Standards for ZYJHK from the UKIDSS and VISTA Surveys

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa310 ◽

2020 ◽

Vol 493 (2) ◽

pp. 2568-2595

Author(s):

S K Leggett ◽

Nicholas J G Cross ◽

Nigel C Hambly

Keyword(s):

Near Infrared ◽

Variable Stars ◽

Calibration Data ◽

Infrared Telescope ◽

Final Sample ◽

Sky Survey ◽

Data Release ◽

Deep Survey ◽

Large Telescopes ◽

Astrometric Data

ABSTRACT The currently defined ‘United Kingdom Infrared Telescope (UKIRT) Faint Standards’ have JHK magnitudes between 10 and 15, with Kmedian = 11.2. These stars will be too bright for the next generation of large telescopes. We have used multi-epoch observations taken as part of the UKIRT Infrared Deep Sky Survey (UKIDSS) and the Visible and Infrared Survey Telescope for Astronomy (VISTA) surveys to identify non-variable stars with JHK magnitudes in the range 16–19. The stars were selected from the UKIDSS Deep Extragalactic Survey and Ultra Deep Survey, the WFCAM calibration data (WFCAMCAL08B), the VISTA Deep Extragalactic Observations (VIDEO), and UltraVISTA. Sources selected from the near-infrared databases were paired with the Pan-STARRS Data Release 2 of optical to near-infrared photometry and the Gaia astrometric Data Release 2. Colour indices and other measurements were used to exclude sources that did not appear to be simple single stars. From an initial selection of 169 sources, we present a final sample of 81 standard stars with ZYJHK magnitudes, or a subset, each with 20 to 600 observations in each filter. The new standards have Ksmedian = 17.5. The relative photometric uncertainty for the sample is <0.006 mag and the absolute uncertainty is estimated to be ≲ 0.02 mag. The sources are distributed equatorially and are accessible from both hemispheres.

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Near Infrared Interferometry with Large Telescopes

Symposium - International Astronomical Union ◽

10.1017/s0074180900221724 ◽

2001 ◽

Vol 205 ◽

pp. 440-446

Author(s):

Francesco Paresce

Keyword(s):

Near Infrared ◽

Infrared Interferometry ◽

Large Telescopes

First fringes with commissioning instruments and siderostats on both the Keck and VLTI facilities are expected for early 2001.

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Infrared Speckle Methods

International Astronomical Union Colloquium ◽

10.1017/s0252921100108486 ◽

1984 ◽

Vol 79 ◽

pp. 309-336 ◽

Cited By ~ 1

Author(s):

A. Chelli

Keyword(s):

Optical Properties ◽

Image Reconstruction ◽

Spatial Resolution ◽

Near Infrared ◽

Speckle Interferometry ◽

Reconstruction Methods ◽

Interferometry Method ◽

Large Telescopes

I-INTRODUCTION The speckle interferometry method has been introduced in 1970 by A. Labeyrie who showed in the visible dcmain that it was possible to reach the limiting spatial resolution of large telescopes. From 1977, the method is extended to the near infrared between 2 and 5ym (Lena, 1977; Wade and Selby, 1978) ,7 years later infrared speckle systems are operating on several large telescopes (ESO, KPNO, AAT, UKIRT, CFHT... ).The speckle interferometry method has allowed to better understanding the optical properties of the atmosphere, especially owing to the work of F.Roddier (Roddier, 1981). It has raised new problems like the phase restitution of the object spectrum and has largely contributed to the development of image reconstruction methods.

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Near Infrared Instrumentation R&D Activities at CEERI Centre, CSIR Complex, Taramani, Chennai, India

NIR news ◽

10.1255/nirn.1208 ◽

2010 ◽

Vol 21 (7) ◽

pp. 14-15

Keyword(s):

Near Infrared ◽

Infrared Instrumentation

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Near Infrared Instrumentation

The Concise Handbook of Analytical Spectroscopy: Theory, Applications, and Reference Materials ◽

10.1142/9789813149502_0003 ◽

2016 ◽

pp. 85-129

Keyword(s):

Near Infrared ◽

Infrared Instrumentation

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Hand-held near-infrared spectrometers: State-of-the-art instrumentation and practical applications

NIR news ◽

10.1177/0960336018796391 ◽

2018 ◽

Vol 29 (7) ◽

pp. 8-12 ◽

Cited By ~ 21

Author(s):

Hui Yan ◽

Heinz W Siesler

Keyword(s):

Growth Rate ◽

Near Infrared ◽

State Of The Art ◽

Field Testing ◽

Present Communication ◽

Mid Infrared ◽

Practical Applications ◽

Mir Spectroscopy ◽

Infrared Instrumentation ◽

Substantial Progress

Recently, miniaturization of Raman, mid-infrared and near-infrared spectrometers has made substantial progress, and marketing companies predict for this segment of instrumentation a significant growth rate within the next few years. This increase will be based on a more frequent implementation for industrial quality and process control and a wider adoption of spectrometers for in-the-field testing and onsite measurements. However, contrary to Raman and MIR spectroscopy, miniaturization has been much further driven for near-infrared instrumentation. Thus, the present communication will focus on hand-held near-infrared spectrometers only and discuss their applications to selected analytical problems.

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Monitoring Neptune's atmosphere with a combination of small and large telescopes

10.5194/egusphere-egu2020-10443 ◽

2020 ◽

Author(s):

Ricardo Hueso ◽

Imke de Pater ◽

Amy Simon ◽

Mike Wong ◽

Larry Sromovsky ◽

...

Keyword(s):

Adaptive Optics ◽

Near Infrared ◽

Hubble Space Telescope ◽

Vertical Wind Shear ◽

Apparent Size ◽

Absorption Bands ◽

High Resolution Data ◽

Cloud Systems ◽

Methane Absorption ◽

Large Telescopes

<p>Neptune&#8217;s atmosphere is covered by tropospheric clouds and elevated hazes that are highly contrasted in hydrogen and methane absorption bands that dominate the red and near-infrared spectrum of the planet. The major cloud systems observed in these wavelengths evolve in time-scales of days, months and years. However, the differential rotation of the atmosphere, and the vertical wind shear implied by the motion of some of these systems, result in challenges in identifying common cloud systems observed in images obtained with a time difference of only a few weeks. Given the small apparent size of Neptune&#8217;s disk (2.3 arc sec at best) there are outstanding difficulties in obtaining sufficient high-resolution data to trace Neptune&#8217;s atmospheric dynamics and study the variability in the atmosphere.</p><p>In 2019 Neptune has been observed by a battery of different large telescopes and techniques including: Adaptive Optics observations from the Keck, Lick and other telescopes, observations from Hubble Space Telescope in two different dates, and lucky-imaging observations with the GranTeCan 10.4m, Calar Alto 2.2m and the 1.05m Pic du Midi telescope. In addition, some ground-based observers using small telescopes of 30-40 cm have been successful to image Neptune&#8217;s major clouds completing a dense time-line of observations. We will present comparative results of Neptune&#8217;s major cloud systems observed with these facilities at a variety of spatial resolutions and long-term drift rates of some of these cloud systems. These will be compared with similar multi-telescope results obtained in the past with several of these telescopes since 2015. Future punctual observations achievable with new observational facilities such as the JWST will benefit from ground-based coordinated campaigns and will require a combination of several telescopes to understand drift rates and evolutionary time-lines of major cloud systems in Neptune.</p>

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