The molecular interstellar medium and the near-infrared continuum of the barred liner NGC 6764

1991 ◽  
Vol 372 ◽  
pp. 67 ◽  
Author(s):  
A. Eckart ◽  
M. Cameron ◽  
J. M. Jackson ◽  
R. Genzel ◽  
A. I. Harris ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Near Infrared ◽  
Infrared Continuum

Visible to near-infrared continuum generation in a water-core photonic crystal fiber

2008 ◽  
Author(s):  
Alexandre Bozolan ◽  
Cristiano M. B. Cordeiro ◽  
Christiano J. S. de Matos ◽  
Eliane M. dos Santos ◽  
Carlos H. Brito Cruz ◽  
...  
Keyword(s):  
Photonic Crystal ◽  
Photonic Crystal Fiber ◽  
Near Infrared ◽  
Continuum Generation ◽  
Crystal Fiber ◽  
Infrared Continuum

scholarly journals Low Frequency Cutoffs in the Spectra of Radioquiet Quasars

1987 ◽  
Vol 121 ◽  
pp. 135-139
Author(s):  
R. Antonucci ◽  
R. Barvainis
Keyword(s):  
High Frequency ◽  
Near Infrared ◽  
Dust Emission ◽  
Low Frequency ◽  
Far Infrared ◽  
Low Energy Electrons ◽  
Order Of Magnitude ◽  
Infrared Continuum ◽  
Lower Cutoff ◽  
Rule Out

Radio-quiet and normal radio-loud quasars have very similar spectral properties in the ultraviolet, optical and near infrared regions, but their radio powers differ by several orders of magnitude. Somewhere between the near infrared and the radio their spectra must diverge dramatically.The IRAS survey detected 17 radio quiet quasars and luminous Seyfert 1's with −29. 5 ≤ Mv ≤ −21.6 (for Ho = 75). By coadding the survey data and using pointed observations, we have detections of most of these objects in all four IRAS passbands. The spectra are all rising with wavelength all the way to 100μ. We are measuring fluxes in the centimeter, millimeter, and, together with R Cutri, the near infrared and optical regions for each of these objects. Our goal is to constrain the location, shape, and spectral context of the low frequency cutoffs. Here we present the IRAS, millimeter and centimeter data. Measurements at the other wavelengths are still in progress.Although the spectra are rising steeply between 60μ and 100μ, we find that all of our objects are undetectable at 1.3 mm with the NRAO 12-m telescope. Our limits are typically an order of magnitude below the 100μ fluxes. (Ennis et al (1982) and Robson et al (1985) have already shown that the 1 mm fluxes of some radio quiet quasars must be below the extrapolation of the near infrared continuum.) Our objects are all extremely weak or undetected with the VLA at 2 cm and 1.3 cm, at levels typically three orders of magnitude below the 100μ fluxes. The sharpness of the required cutoffs allows us to rule out the hypothesis that the infrared is synchrotron radiation with the cutoff due to an absence of low energy electrons. The high frequency of the cutoffs makes free-free absorption implausible, but not impossible. It is possible that synchrotron self-absorption is suppressing the radio. There is circumstantial evidence that the far infrared is thermal dust emission. This would require a lower cutoff in the distribution of dust temperatures, which we think we can explain.

scholarly journals Near‐Infrared Molecular Hydrogen Emission from the Central Regions of Galaxies: Regulated Physical Conditions in the Interstellar Medium

2004 ◽  
Vol 609 (2) ◽  
pp. 692-709 ◽  
Author(s):  
Soojong Pak ◽  
D. T. Jaffe ◽  
G. J. Stacey ◽  
C. M. Bradford ◽  
Eric W. Klumpe ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Molecular Hydrogen ◽  
Near Infrared ◽  
Hydrogen Emission ◽  
Physical Conditions ◽  
Central Regions

PUMILA: a near-infrared spectrograph for the kinematic study of the interstellar medium

1998 ◽  
Author(s):  
Margarita Rosado ◽  
Irene Cruz-Gonzales ◽  
Luis Salas ◽  
Abel Bernal ◽  
Francisco J. Cobos Duenas ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Near Infrared ◽  
Kinematic Study

scholarly journals 7.4. The 3.4 micron absorption in the Galactic center sources

1998 ◽  
Vol 184 ◽  
pp. 299-300
Author(s):  
T. Nagata
Keyword(s):  
Interstellar Medium ◽  
Near Infrared ◽  
Galactic Center ◽  
Absorption Feature ◽  
Visual Extinction ◽  
Stretching Vibrations ◽  
Central Parsec ◽  
Infrared Sources

The 3.4μm absorption feature, first detected in the Galactic center source IRS7 (Soifer et al., 1976), has been observed in other Galactic center sources IRS3, IRS12 (McFadzean et al., 1989), and IRS6E (Pendleton et al., 1994). This feature is regarded as characteristic of dust in the diffuse interstellar medium, and attributed to C-H stretching vibrations. Several objects in the lines of sight other than the Galactic center is now known to have the feature (Sandford et al. 1995 and references therein; Imanishi et al. 1996). The absorption depths per unit visual extinction τ3.4/AV for these sources are compared with those for the Galactic center sources, and they are thought to increase near the Galactic center. However, the “Galactic center” sources are all in the central parsec cluster, and the features observed in them may be only representative of interstellar medium local to the central parsec, not the general diffuse interstellar medium of the inner Galaxy. In this paper, we report the 3.4μm absorption feature detected in near-infrared sources within 1° of the Galactic center.

scholarly journals Near-Infrared Spectroscopy of the Diffuse Galactic Emission

2012 ◽  
Vol 10 (H16) ◽  
pp. 703-704
Author(s):  
T. Onaka ◽  
I. Sakon ◽  
R. Ohsawa ◽  
T. I. Mori ◽  
H. Kaneda ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Interstellar Medium ◽  
Near Infrared Spectroscopy ◽  
Emission Band ◽  
Near Infrared ◽  
Infrared Camera ◽  
Nir Spectroscopy ◽  
Ionized Gas ◽  
Band Ratio ◽  
Galactic Emission

AbstractThe near-infrared (NIR) spectral range (2–5 μm) contains a number of interesting features for the study of the interstellar medium. In particular, the aromatic and aliphatic components in carbonaceous dust can be investigated most efficiently with the NIR spectroscopy. We analyze NIR spectra of the diffuse Galactic emission taken with the Infrared Camera onboard AKARI and find that the aliphatic to aromatic emission band ratio decreases toward the ionized gas, which suggests processing of the band carriers in the ionized region.

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