SPECTRAL TYPING OF LATE-TYPE STELLAR COMPANIONS TO YOUNG STARS FROM LOW-DISPERSION NEAR-INFRARED INTEGRAL FIELD UNIT DATA

Abstract Observations of transient objects, such as short gamma-ray bursts and electromagnetic counterparts of gravitational wave sources, require prompt spectroscopy. To carry out prompt spectroscopy, we have developed an optical-fiber integral field unit (IFU) and connected it with an existing optical spectrograph, KOOLS. KOOLS–IFU was mounted on the Okayama Astrophysical Observatory 188 cm telescope. The fiber core and cladding diameters of the fiber bundle are 100 μm and 125 μm, respectively, and 127 fibers are hexagonally close-packed in the sleeve of the two-dimensional fiber array. We conducted test observations to measure the KOOLS–IFU performance and obtained the following conclusions: (1) the spatial sampling is ${2{^{\prime\prime}_{.}}34}$$\, \pm \,$${0{^{\prime\prime}_{.}}05}$ per fiber, and the total field of view is ${30{^{\prime\prime}_{.}}4}$$\, \pm \,$${0{^{\prime\prime}_{.}}65}$ with 127 fibers; (2) the observable wavelength and the spectral resolving power of the grisms of KOOLS are 4030–7310 Å and 400–600, 5020–8830 Å and 600–900, 4160–6000 Å and 1000–1200, and 6150–7930 Å and 1800–2400, respectively; and (3) the estimated limiting magnitude is 18.2–18.7 AB mag during 30 min exposure under optimal conditions.

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The Integral Field Unit of the Near Infrared Spectrograph for JWST

Eso Astrophysics Symposia - Science Perspectives for 3D Spectroscopy ◽

10.1007/978-3-540-73491-8_3 ◽

2009 ◽

pp. 21-26 ◽

Cited By ~ 1

Author(s):

S. Arribas ◽

P. Ferruit ◽

P. Jakobsen ◽

T. Boeker ◽

A. Bunker ◽

...

Keyword(s):

Near Infrared ◽

Field Unit ◽

Integral Field

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Near-infrared Integral-Field Spectrograph (NIFS): An Instrument Proposed for Gemini

Publications of the Astronomical Society of Australia ◽

10.1071/as99273 ◽

1999 ◽

Vol 16 (3) ◽

pp. 273-287 ◽

Cited By ~ 10

Author(s):

Peter J. McGregor ◽

Peter Conroy ◽

Gabe Bloxham ◽

Jan van Harmelen

Keyword(s):

Control System ◽

Near Infrared ◽

High Efficiency ◽

Low Cost ◽

High Redshift ◽

Target Velocity ◽

Wide Range ◽

Integral Field Spectrograph ◽

Field Unit ◽

Integral Field

AbstractIn late 1998 the International Gemini Project Office identified a need for a low cost, near-infrared spectrograph to be commissioned on the Gemini South telescope on the shortest possible timescale. In response, the Research School of Astronomy and Astrophysics of the Australian National University proposed to design, construct, and commission a near-infrared, integral-field spectrograph on Gemini. The science drivers and novel design of the Near-infrared Integral-Field Spectrograph (NIFS) are described in this paper. NIFS will achieve significant economies in cost and schedule in several ways:• By addressing targeted science with high efficiency. NIFS will primarily target velocity measurements in galaxies to study the demographics of black holes in galactic nuclei and the evolution of structural properties in high redshift galaxies. However, NIFS will also be applied to a wide range of general astronomical topics, but these will not dictate the instrument design.• By adopting a largely fixed-format design. A 3·2″ × 3·2″ ‘stair-case’ integral field unit (IFU) will feed a near-infrared spectrograph with four fixed-angle gratings mounted on a single grating wheel. A single, fixed-format camera will form the spectral image on a 2048 × 2048 Rockwell HgCdTe HAWAII-2 array. Two-pixel spectral resolving powers of ∼5400 will be achieved with complete wavelength coverage in each of the J, H, and K photometric bands through 32 optimally sampled 0·1″ wide slitlets. The velocity resolution of ∼55 km s−1 will be sufficient to achieve the targeted science objectives, and will allow software rejection of OH airglow lines.• By packaging the NIFS instrument within a duplicate of the Near-Infrared Imager (NIRI) cryostat. The NIRI cryostat, On-Instrument Wavefront Sensor (OIWFS), detector focusing mechanism, control system, and EPICS software will all be duplicated with only minimal change. Construction of the duplicate NIRI cryostat, OIWFS, and control system will be done by the University of Hawaii.

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Regrowth of stellar disks in mature galaxies: The two component nature of NGC 7217 revisited with VIRUS-W

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314009363 ◽

2014 ◽

Vol 10 (S309) ◽

pp. 81-84

Author(s):

Maximilian H. Fabricius ◽

Lodovico Coccato ◽

Ralf Bender ◽

Niv Drory ◽

Claus Gössl ◽

...

Keyword(s):

Rotating Disk ◽

High Spectral Resolution ◽

Morphological Evidence ◽

Interstellar Gas ◽

Counter Rotation ◽

Stellar Component ◽

Stellar Halo ◽

Field Unit ◽

Low Dispersion ◽

Integral Field

AbstractWe have obtained high spectral resolution (R ≈ 9000), integral field observations of the three spiral galaxies NGC 3521, NGC 7217 and NGC 7331 using the new fiber-based Integral Field Unit instrument VIRUS-W at the 2.7 m telescope of the McDonald Observatory in Texas. Our data allow us to revisit previous claims of counter rotation in these objects. A detailed kinematic decomposition of NGC 7217 shows that no counter rotating stellar component is present. We find that NGC 7217 hosts a low dispersion, rotating disk that is embedded in a high velocity dispersion stellar halo or bulge that is co-rotating with the disk. Due to the very different velocity dispersions (≈ 20 km s−1 vs. 150 km s−1) , we are further able to perform a Lick index analysis on both components separately which indicates that the two stellar populations are clearly separated in (Mgb,〈Fe〉) space. The velocities and dispersions of the faster component are very similar to those of the interstellar gas as measured from the [O iii] emission. Morphological evidence of active star formation in this component further suggests that NGC 7217 may be in the process of (re)growing a disk inside a more massive and higher dispersion stellar halo.

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VIRUS-W A fiber based integral field unit spectrograph for the study of galaxy bulges

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308018279 ◽

2007 ◽

Vol 3 (S245) ◽

pp. 417-418

Author(s):

Maximilian H. Fabricius ◽

Ralf Bender ◽

Niv Drory ◽

Frank Grupp ◽

Gary J. Hill ◽

...

Keyword(s):

Optical Fibers ◽

Spectral Resolution ◽

Field Of View ◽

Late Type ◽

Field Unit ◽

Integral Field

AbstractWe presented the design for a fiber based integral field unit spectrograph for the new two meter class Wendelstein telescope in Bavaria, Germany. The proposed spectrograph will feature a fiberhead consisting of 246 individual optical fibers and a field of view of approximately 1′ × 2′ and two different spectral resolution modes optimized for the study of bulges of local late-type galaxies.

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AGN-starburst connection in NGC 7582: Gemini near-infrared spectrograph integral field unit observations

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2008.14250.x ◽

2009 ◽

Vol 393 (3) ◽

pp. 783-797 ◽

Cited By ~ 66

Author(s):

Rogemar A. Riffel ◽

Thaisa Storchi-Bergmann ◽

Oli L. Dors ◽

Cláudia Winge

Keyword(s):

Near Infrared ◽

Field Unit ◽

Integral Field

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A HIGH RESOLUTION INTEGRAL FIELD SPECTROGRAPH FOR THE EUROPEAN SOLAR TELESCOPE

Journal of Astronomical Instrumentation ◽

10.1142/s2251171713500074 ◽

2013 ◽

Vol 02 (01) ◽

pp. 1350007 ◽

Cited By ~ 4

Author(s):

A. CALCINES ◽

R. L. LÓPEZ ◽

M. COLLADOS

Keyword(s):

High Resolution ◽

Near Infrared ◽

Optical Quality ◽

Solar Chromosphere ◽

Solar Telescope ◽

Infrared Wavelength ◽

Multi Wavelength ◽

Integral Field Spectrograph ◽

Field Unit ◽

Integral Field

This paper presents the proposal of a high resolution, integral field spectrograph that is currently being designed for the 4-meter aperture European Solar Telescope that will be located in the Canary Islands. This instrument is optimized to study the solar chromosphere and photosphere to allow the investigation of several phenomena concentrated within these two layers. It will be able to observe simultaneously a bidimensional field of view of 80 arcsec2 that is reorganized, using an integral field unit, into 8 long slits of 200 arcsec length by 0.05 arcsec width. It will have the capability to observe different layers of the Sun at the same time due to its multi-wavelength capability that allows the observation of 5 visible and 3 near-infrared wavelength intervals from 3900 to 23,000 Å, with a spectral resolution of about 300,000. The designed instrument is telecentric and presents an optical quality limited by diffraction.

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