Detection of two interstellar absorption bands coincident with spectral features of C60+

Nature ◽  
1994 ◽  
Vol 369 (6478) ◽  
pp. 296-298 ◽  
Author(s):  
B. H. Foing ◽  
P. Ehrenfreund
Keyword(s):  
Spectral Features ◽  
Absorption Bands ◽  
Interstellar Absorption

Origin of the Diffuse Interstellar Absorption Bands

Nature ◽  
1968 ◽  
Vol 218 (5137) ◽  
pp. 153-153 ◽  
Author(s):  
W. W. DULEY
Keyword(s):  
Absorption Bands ◽  
Interstellar Absorption

scholarly journals Electron Dynamics in Anatase TiO2 Nanoparticles by Ultrafast Broadband Deep-Ultraviolet Spectroscopy

2019 ◽  
Vol 205 ◽  
pp. 05017
Author(s):  
Edoardo Baldini ◽  
Tania Palmieri ◽  
Enrico Pomarico ◽  
Gerald Auböck ◽  
Majed Chergui
Keyword(s):  
Lattice Dynamics ◽  
Anatase Tio2 ◽  
Spectral Features ◽  
Electron Dynamics ◽  
Electron Cooling ◽  
Absorption Bands ◽  
Bulk Absorption ◽  
Anatase Nanoparticles ◽  
Deep Ultraviolet ◽  
Broadband Spectroscopy

The optical bandgap of anatase TiO2 nanoparticles is dominated by bulk absorption bands in the deep-ultraviolet due to strongly bound excitons. These spectral features can be utilized as a sensitive probe of carrier and lattice dynamics inside the TiO2 nanoparticles. Here, we implement ultrafast broadband spectroscopy tuned to the exciton resonances in order to track the electron cooling in the conduction band of bare anatase nanoparticles and monitor the electron injection dynamics from an external dye in the case of sensitized anatase nanoparticles.

scholarly journals Optical and Chemical Studies on Simulated Interstellar Grain Materials

1973 ◽  
Vol 52 ◽  
pp. 327-333
Author(s):  
J. D. McCullough ◽  
G. R. Floyd ◽  
R. H. Prince ◽  
W. W. Duley
Keyword(s):  
Wavelength Range ◽  
Absorption Bands ◽  
Interstellar Absorption ◽  
Interstellar Grains ◽  
Chemical Studies ◽  
Radiation Induced ◽  
Absorption Features ◽  
Important Constituent

The possibility that many different diffuse interstellar absorption features may be produced by the same type of absorbing atom in different hydrocarbon matrices on interstellar grains has been examined experimentally. The present study shows that absorption bands due to Na atoms in various hydrocarbon matrices can occur within the wavelength range 5400–5800 Å. A study of the molecules generated from the radiation-induced polymerization of C2H2 at 55 K is also reported. It is shown that C6H6 is an abundant product of this polymerization and may therefore be an important constituent of interstellar grains.

scholarly journals The Mg II Features Near 2800Å and Spectral Classification

1977 ◽  
Vol 4 (2) ◽  
pp. 363-364
Author(s):  
Yoji Kondo
Keyword(s):  
The Other ◽  
Absorption Lines ◽  
Spectral Features ◽  
The Sun ◽  
Spectral Classification ◽  
Interstellar Absorption ◽  
B Stars ◽  
The Core ◽  
Chromospheric Emission

The Mg II resonance lines at 2795.523 and 2802.698Å and their respective subordinate lines at 2797.989 and 2790.768Å are probably among the most prominent and interesting spectral features in the ultraviolet; they are perhaps the most significant in the mid-ultraviolet. They are also observable in one form or the other in stars of practically all spectral types. We shall discuss relatively high (about 0.4Å) resolution observations of these features.In the early spectral types both the resonance and subordinate lines are seen primarily as absorption lines. An interstellar absorption of varying strengths is superimposed on the photospheric absorption of the resonance lines. The strengths of the photospheric resonance and subordinate lines increase from 0 to B, e.g., Lamers et al. (1973) and Kondo et al. (1975). The subordinate lines begin to merge with the resonance lines in late-B stars. In mid-A type stars, the resonance and subordinate absorption strengths become maximum. In F-type stars, the photospheric absorption strenghts continue to decrease. Chromospheric emissions become definitely detectable in F-type stars (Kondo et al. 1972). In a G2 V star, the sun, the chromospheric emission is fairly prominent at the core of relatively weak photospheric absorption. In K and M-type stars, this region is presumably dominated by the chromospheric emissions of Mg II resonance lines with the photospheric absorption becoming negligible in late-K stars; the only extant observation in this region is that of e Eri (K2 V) (McClintock et al. 1975).

scholarly journals Diurnal variation of midlatitudinal NO<sub>3</sub> column abundance over Table Mountain Facility, California

2010 ◽  
Vol 10 (8) ◽  
pp. 20193-20237
Author(s):  
C. M. Chen ◽  
R. P. Cageao ◽  
L. Lawrence ◽  
J. Stutz ◽  
R. J. Salawitch ◽  
...  
Keyword(s):  
Full Moon ◽  
Optical Absorption Spectroscopy ◽  
Spectral Features ◽  
Free Troposphere ◽  
Absorption Bands ◽  
Model Calculations ◽  
Diurnal Variability ◽  
One Dimensional ◽  
Lunar Occultation ◽  
Table Mountain

Abstract. The column abundance of NO3 was measured over Table Mountain Facility, CA (34.4° N, 117.7° W) from May 2003 through September 2004, using lunar occultation near full moon with a grating spectrometer. The NO3 column retrieval was performed with the differential optical absorption spectroscopy (DOAS) technique using both the 623 and 662 nm NO3 absorption bands. Other spectral features such as Fraunhofer lines and absorption from water vapor and oxygen were removed using solar spectra obtained at different airmass factors. We observed a seasonal variation, with nocturnally averaged NO3 columns between 5–7×1013 molec cm−2 during October through March, and 5–22×1013 molec cm−2 during April through September. A subset of the data, with diurnal variability vastly different from the temporal profile obtained from one-dimensional stratospheric model calculations, clearly has boundary layer contributions; this was confirmed by simultaneous long-path DOAS measurements. However, even the NO3 columns that did follow the modeled time evolution were often much larger than modeled stratospheric partial columns constrained by realistic temperatures and ozone concentrations. This discrepancy is attributed to substantial tropospheric NO3 in the free troposphere, which may have the same time dependence as stratospheric NO3.

Diffuse interstellar absorption bands

2009 ◽  
Vol 52 (4) ◽  
pp. 489-501 ◽  
Author(s):  
FuYuan Xiang ◽  
ShunLin Liang ◽  
AiGen Li
Keyword(s):  
Absorption Bands ◽  
Interstellar Absorption

An Infrared Study of Metal Isopropoxide Precursors for SrTiO3

1984 ◽  
Vol 32 ◽  
Author(s):  
R. E. Riman ◽  
D. M. Haaland ◽  
C.J.M. Northrup ◽  
H. K. Bowen ◽  
A. Bleier
Keyword(s):  
Ir Spectra ◽  
Detailed Analysis ◽  
Infrared Spectra ◽  
Spectral Features ◽  
Absorption Bands ◽  
Infrared Study ◽  
Characteristic Absorption ◽  
Local Environments ◽  
Insight Into ◽  
Hydrolysis Reactions

ABSTRACTA Sr/Ti bimetallic isopropoxide complex was synthesized by two methods. The complex served as a precursor to the production of homogeneous SrTiO3 powders via alkoxide hydrolysis. Infrared spectra were obtained for Sr(OPri)2, Ti(OPri)4, and the product of the syntheses. In addition, the IR spectra of the solutions of each of the alkoxides were followed as hydrolysis reactions proceeded. Detailed analysis of the spectral features support the existence of a 1:1 Sr/Ti bimetallic alkoxide. The new Sr/Ti compound exhibits characteristic absorption bands at (1017, 993, 972, 961 cm−1), (844, 838, 827 cm−1) and (620, 596, and 572 −1). A band at 819−1 might also be associated with the new Sr/Ti bimetallic alkoxide. The infrared spectra suggest that the isopropoxide ligands in the bimetallic alkoxide are in at least three separate local environments. This information offers insight into possible structures for the complex.

Sign in / Sign up

Export Citation Format

Share Document