8 research outputs found
The Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope: I. Overview of the instrument and its capabilities
We provide an overview of the design and capabilities of the near-infrared
spectrograph (NIRSpec) onboard the James Webb Space Telescope. NIRSpec is
designed to be capable of carrying out low-resolution () prism
spectroscopy over the wavelength range m and higher resolution
( or ) grating spectroscopy over
m, both in single-object mode employing any one of five fixed
slits, or a 3.13.2 arcsec integral field unit, or in multiobject
mode employing a novel programmable micro-shutter device covering a
3.63.4~arcmin field of view. The all-reflective optical chain of
NIRSpec and the performance of its different components are described, and some
of the trade-offs made in designing the instrument are touched upon. The
faint-end spectrophotometric sensitivity expected of NIRSpec, as well as its
dependency on the energetic particle environment that its two detector arrays
are likely to be subjected to in orbit are also discussed
Recommended from our members
The Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope: I. Overview of the instrument and its capabilities
We provide an overview of the design and capabilities of the near-infrared
spectrograph (NIRSpec) onboard the James Webb Space Telescope. NIRSpec is
designed to be capable of carrying out low-resolution () prism
spectroscopy over the wavelength range m and higher resolution
( or ) grating spectroscopy over
m, both in single-object mode employing any one of five fixed
slits, or a 3.13.2 arcsec integral field unit, or in multiobject
mode employing a novel programmable micro-shutter device covering a
3.63.4~arcmin field of view. The all-reflective optical chain of
NIRSpec and the performance of its different components are described, and some
of the trade-offs made in designing the instrument are touched upon. The
faint-end spectrophotometric sensitivity expected of NIRSpec, as well as its
dependency on the energetic particle environment that its two detector arrays
are likely to be subjected to in orbit are also discussed
Ultrasensitive Molecule Detection Based on Infrared Metamaterial Absorber with Vertical Nanogap
Surface-enhanced infrared absorption (SEIRA) spectroscopy is a powerful methodology for sensing and identifying small quantities of analyte molecules via coupling between molecular vibrations and an enhanced near-field induced in engineered structures. A metamaterial absorber (MA) is proposed as an efficient SEIRA platform; however, its efficiency is limited because it requires the appropriate insulator thickness and has a limited accessible area for sensing. SEIRA spectroscopy is proposed using an MA with a 10 nm thick vertical nanogap, and a record-high reflection difference SEIRA signal of 36% is experimentally achieved using a 1-octadecanethiol monolayer target molecule. Theoretical and experimental comparative studies are conducted using MAs with three different vertical nanogaps. The MAs with a vertical nanogap are processed using nanoimprint lithography and isotropic dry etching, which allow cost-effective large-area patterning and mass production. The proposed structure may provide promising routes for ultrasensitive sensing and detection applications