Induced Anisotropy and Light Scattering in Liquids. II.

1974 ◽  
Vol 52 (23) ◽  
pp. 2436-2444 ◽  
Author(s):  
H. E. Howard-Lock ◽  
R. S. Taylor
Keyword(s):  
Line Width ◽  
Induced Anisotropy ◽  
Molecular Liquids ◽  
Interaction Length ◽  
Narrow Component ◽  
Proportionality Constant ◽  
Broad Component ◽  
Least Squares Curve Fitting ◽  
Integrated Intensities ◽  
Lorentzian Form

The spectra of light scattered by molecular liquids have been studied in order to obtain information about motions in the liquid on a time scale of 10−11 to 10−13 s. Integrated intensities and polarization ratios were measured. The spectra were decomposed by least squares curve fitting techniques into two components: a narrow component of Lorentzian form with line width approximately constant for all the liquids, and a broad component of the form [Formula: see text] with a line width parameter 1/ν0 equal to 2πγ−1(μ/kT)1/2. The proportionality constant γ−1 has the value of 0.62 Å for all the liquids studied. This interaction length appears to be common to all liquids.

scholarly journals Variation of Broad Optical Emission Lines in AGN's

1994 ◽  
Vol 159 ◽  
pp. 439-439
Author(s):  
N.G. Bochkarev ◽  
A.I. Shapovalova ◽  
L.S. Nazarova
Keyword(s):  
Signal To Noise Ratio ◽  
General Pattern ◽  
Optical Emission ◽  
Special Astrophysical Observatory ◽  
Characteristic Time Scale ◽  
Time Lags ◽  
North Caucasus ◽  
Ngc 4151 ◽  
Broad Component ◽  
Integrated Intensities

AGN optical spectra (4000–5000Å) have been obtained with the TV scanner of the 6-m telescope at Special Astrophysical Observatory (N. Arkhiz-North Caucasus) from 1986 to now. Most spectra were obtained with dispersion of 1 Å/channel and with 3–4Å spectral resolution and signal-to-noise ratio S/N=10–25 for individual spectra. NGC 4151, NGC 3516, NGC 5548 and NGC 7469 are the main sources of the programme and are also being used in international AGN watch programmes for diagnosis, estimation of the size and structure of the BLR.NGC4151:In 1987 the broad components of the Hβ and Hγ lines decreased strongly (on about 65% as compared with 1986) and fell to a level comparable to that of 1984. In 1988 they increased up approximately to the level of 1986. During the photometrically low state of NGC 4151 satellites of the strong Hβ, Hγ, Hδ and He II4686Å lines were suspected at radial velocities of +9400 km/s and −7500 km/s. The data are could be interprite a two-jet model with jet velocity of 8400–24000 km/s. (Bochkarev et al., 1989). Analysis of the spectra shows that the broad component of HeII λ 4686Å changed its asymmetry over 6 years. Bochkarev et al. (1992), Nazarova et al. (1993) discussed a possible explanation of profile HeII λ 4686Å behavior by involving a precession of cones of ionizing radiation.NGC5548:Cross-correction of the optical emission line light curves with the UV continuum light curve reveals that the lines respond to continuum variations with a time delay from 7 days for HeII 4686Å to 18 days for Hβ. Hγ responds more rapidly than the lower order Balmer lines and there is a general trend towards higher amplitude variations in higher-order lines. The time lags for the line variations are consistent with the general pattern of radial ionization stratification of the BLR. During 1988–89 Fe II in blend 4130Å varies with an amplitude of aproximately 20% about the mean, similar the amplitude of the Hβ variations and Balmer continuum.NGC3516:Variations of Hβ during 1986–88 were small (20%), the shape of the profile (including the assymetry) did not change, but Hγ - to Hβ ratios of the profile integrated intensities of broad component increased from 0.43 in 1986 to 0.8 in 1988. The 30% variations of continuum on characteristic time scale 10–15 days during the spring of 1988 were not accompanied by any noticeable changes in the line profile (Bochkarev et al., 1990).

Dependence of Light-Induced Esr on NitroGen Content in Amorphous Silicon-Nitrogen Alloys

1996 ◽  
Vol 420 ◽  
Author(s):  
Jinyan Zhang ◽  
Toshihiro Ohtsuka ◽  
Minoru Kumeda ◽  
Tatsuo Shimizu
Keyword(s):  
Amorphous Silicon ◽  
Nitrogen Content ◽  
Dangling Bond ◽  
Narrow Component ◽  
Broad Component ◽  
Wide Range ◽  
G Value ◽  
Three Components

AbstractThe LESR signals are observed for the a-Si1-xNx:H samples over a wide range of nitrogen content at 77K. By decomposing the LESR signals using three components, i.e. the neutral Si dangling bond (Do) component, the broad component with a linewidth of 16 G, and the narrow component with a linewidth of 5 G, we find that the three components are observed only in the Si-rich samples. The density of light-induced Do increases with x, whereas the densities of both the narrow and the broad components increase in the range of x≦0.32 and are almost independent of x for larger x. The g-value of the broad components falls down sharply from 2.01 to 2.006 with an increase in x, while the g-value of the narrow component is unchanged and it is around 2.004. All of the three components can be annihilated by sub-gap illumination. The origins of the broad and the narrow components are discussed.

ESR Study of Electrochemically Doped Chalcogenide Nanotubes

2003 ◽  
Vol 775 ◽  
Author(s):  
Denis Arcon ◽  
Andrej Zorko ◽  
Pavel Cevc ◽  
Ales Mrzel ◽  
Maja Remskar ◽  
...  
Keyword(s):  
Room Temperature ◽  
Electrochemical Activity ◽  
Chain Model ◽  
Heisenberg Chain ◽  
One Dimensional ◽  
Narrow Component ◽  
Broad Component ◽  
X Band ◽  
Heavily Doped ◽  
The One

AbstractElectrochemical activity of differently pretreated single-wall subnanometer-diameter molybdenum disulfide tubes (nMoS2) was tested and compared with layered MoS2 material. In as prepared and de-iodized nMoS2 samples a significant increase in the charge capacity has been found compared to the one measured in dispersed nMoS2 or layered MoS2. Enhanced electrochemical activity has been attributed to a particular one-dimensional topology of nanotubes bundles. Electrochemically doped samples were then studied with X-band ESR. While undoped nMoS2 show no X-band ESR signal between room temperature and 4 K we found in heavily doped nMoS2 samples two distinct ESR components: a narrow component with a linewidth of few Guass and a broad component with a linewidth of more than 800 G. The broad ESR component is characteristic of Mo d-orbital-derived band. The temperature dependence of the ESR spin susceptibility and the linewidth of the broad ESR component can be discussed either in terms of conducting electrons coupled to defects or in terms of random-exchange Mo Heisenberg chain model.

scholarly journals Emission Line Properties of Seyfert 1 Type AGN from RASS

2003 ◽  
Vol 214 ◽  
pp. 273-274
Author(s):  
D. W. Xu ◽  
S. Komossa ◽  
J. Y. Wei ◽  
X. Z. Zheng ◽  
Y. Qian
Keyword(s):  
Correlation Analysis ◽  
Emission Line ◽  
Optical Emission ◽  
Strong Correlations ◽  
X Ray ◽  
Narrow Component ◽  
Broad Component

We present the optical emission line properties of a sample of 155 bright X-ray selected ROSAT Seyfert 1 type AGN. The measured properties are gathered for correlation analysis. The strong correlations between Hβ redshift, flux ratios of Fe II to Hβ broad component and [O III] to Hβ narrow component are found.

scholarly journals Starburst galaxy NGC 7673: a minor merger remnant

1999 ◽  
Vol 193 ◽  
pp. 743-744
Author(s):  
Nicole L. Homeier ◽  
John S. Gallagher
Keyword(s):  
Rotating Disk ◽  
Starburst Galaxy ◽  
Stellar Winds ◽  
H Ii Regions ◽  
Irregular Galaxy ◽  
Narrow Component ◽  
Broad Component ◽  
The Galaxy ◽  
Hα Emission ◽  
A Minor

We investigate the kinematics of the luminous starburst galaxy NGC 7673 = Mrk 325, a nearby example of a ‘clumpy irregular galaxy’. Images with the WIYN 3.5m telescope reveal outer wisps associated with mergers, and we suggest NGC 7673 is the survivor of a minor merger. DensePak spectroscopy of the Hα kinematics shows that the H II regions are confined to a rotating disk. The Hα emission line velocity field indicates that although there is widespread star formation across the inner disk, it is still rotating smoothly. The Hα emission profiles over the brightest regions of the galaxy have two components: narrow, FWHM ≈ 50kms−1 lines, and broad, FWHMW ≈ 150 km s−1 lines. The width of the narrow lines is likely due to a combination of averaging effects, stellar winds and SNRs, and possibly gravitational motions within the disk. The origin of the broad component, which eclipses the narrow component in flux over much of the galaxy's inner regions, is still unclear. We may be looking at turbulent gas encased in bubbles carved out by massive stars and their descendants, or possibly some localized outflows from the disk.

scholarly journals Rotational Velocities of B, A, and Early-F Stars

2004 ◽  
Vol 215 ◽  
pp. 53-54
Author(s):  
Francis C. Fekel ◽  
Phillip B. Warner ◽  
Anthony B. Kaye
Keyword(s):  
Radial Velocity ◽  
Early Type ◽  
Narrow Component ◽  
Broad Component ◽  
F Stars

Projected rotational velocities for 67 B, A, and early-F stars have been determined. Some of these stars are early-type, radial-velocity standard candidates. The spectra of seven stars show metallic lines with composite profiles that consist of a narrow component near the center of a broad component, suggesting that they may be shell stars or binaries.

scholarly journals Gas Kinematics of the Disk and Bar of the Galaxy Mrk 533

1996 ◽  
Vol 157 ◽  
pp. 233-235 ◽  
Author(s):  
V. L. Afanasiev ◽  
I. P. Kostiuk
Keyword(s):  
Angular Size ◽  
Morphological Description ◽  
Narrow Component ◽  
Gas Kinematics ◽  
Broad Component ◽  
Fabry Perot ◽  
The Galaxy ◽  
Galaxy Disk ◽  
Scanning Interferometer ◽  
Spectral Channels

The Seyfert 2 galaxy Mrk 533 has the morphological description of SA(r)bc pec in RC3 and SBb in UGC. It is a member of the compact group of galaxies H96. Radio observations (Unger et al. 1988) show three radio sources.3-D observations with a Fabry-Perot scanning interferometer (the number of spectral channels is 32 by 0.44 Å, angular size of 1 px is , the accuracy of radial velocity determination is 10 km s−1) and multi-pupil integral spectrograph observations (the dispersion is 1.16 Å px−1, lens array is 10×16, angular size of each lens is × ) were obtained in the red spectral range at the 6-m telescope. The estimated seeing was about 2″. In the central region of the galaxy (r ≥ 5″, interferometer observations) the Hα line profile was fitted by two Gaussians. The first component, Kl, corresponds to the galaxy disk. The second component, K2, is visible only in the central part and is brighter than K1 in the same pixels. Profiles of Hα and [NII] Λ6584/48 (integral spectroscopy observations) were fitted by two Gaussians. They are a broad component in Hα and [NII] with FWHM ~ 1000 km s−1 and a narrow component of three times less FWHM. The lower spectral resolution of this observation made it impossible to separate the narrow component into the two ones visible in the Fabry-Perot observations.

scholarly journals Time-Resolved Optical Spectroscopy of AM Her X-Ray Sources

1987 ◽  
Vol 93 ◽  
pp. 613-624
Author(s):  
M. Mouchet ◽  
S.F. Van Amerongen ◽  
J.M. Bonnet-Bidaud ◽  
J.P. Osborne
Keyword(s):  
Radial Velocity ◽  
Time Resolution ◽  
Emission Lines ◽  
High Time Resolution ◽  
Rapid Variability ◽  
Time Resolved ◽  
X Ray ◽  
Narrow Component ◽  
Broad Component

AbstractWe present high-time resolution spectroscopy of two AM Her sources E1405−451 and E1013−477. For E1405−451, the Balmer emission lines profiles can be divided into a narrow component and a broad one. The amplitudes of the radial velocity curves of these components are respectively 265±30 km/s and 390±50 km/s. The orientation of the column determined from polarimetry is not compatible with the broad component being formed in the lowest parts of the column. Photometric and spectroscopic results on E1013−477 do not confirm the previous reported 103 min. period. Rapid variability (<1.5h) as well as long term modulation (>3.3h) is present in these data.

scholarly journals Analysis of interacting and isolated quasars

2018 ◽  
Vol 615 ◽  
pp. A11 ◽  
Author(s):  
L. Donoso ◽  
M. V. Alonso ◽  
D. García Lambas ◽  
G. Coldwell ◽  
E. O. Schmidt ◽  
...  
Keyword(s):  
Radial Velocity ◽  
Statistical Study ◽  
Sloan Digital Sky Survey ◽  
Spectral Lines ◽  
Emission Lines ◽  
Host Galaxy ◽  
Galaxy Interactions ◽  
Narrow Component ◽  
Broad Component ◽  
Sky Survey

Aims. The main goal of this study was to determine the effects on equivalent widths (EWs) of some spectral lines produced in the quasars by the presence of surrounding galaxies. To carry this out, a sample of 4663 quasars (QSOs) in the redshift range of 0.20 to 0.40 from the Sloan Digital Sky Survey data release 7 was analyzed. Methods. Three QSO sub-samples were defined, taking into account the projected separations and radial velocity differences with neighboring galaxies. In this way, we utilized two sub-samples of QSOs with strong and weak galaxy interactions, with projected separations smaller than 70 kpc, and between 70 and 140 kpc, respectively, and with radial velocity differences less than 5000 km s−1. These sub-samples were compared with isolated QSOs defined as having greater projected separations and radial velocity differences to the galaxies. Results. From a statistical study of the EWs of relevant spectral lines in the QSOs, we show an increment of the EWs of about 20% in the [OIII]λλ4959, 5007 lines and 7% in Hα for QSOs with stronger galaxy interactions relative to the isolated QSOs. These increments were also observed restricting the sub-samples to velocity differences of 3000 km s−1. These results indicate that some line EWs of QSOs could be marginally influenced by the environment and that they are not affected by the emission of the host galaxy, which was estimated to be around 10% of the total emission. Furthermore, in order to gain a better understanding of the origin of the Hα emission line, we performed broad and narrow line decomposition in 100 QSOs in the restricted Sint sub-sample and also 100 randomly selected QSOs in the Iso sub-sample. When these QSOs were compared, the narrow component remained constant whereas the broad component was incremented. Our results, which reveal slight differences in EWs of some emission lines, suggest that galaxy interactions with QSOs may affect the QSO activity.

Potential Role for Charged Dangling Bonds in Transient-Lesr of Light-Soaked a-Si:H

1992 ◽  
Vol 258 ◽  
Author(s):  
Z. M. Saleh ◽  
H. Tarui ◽  
S. Tsuda ◽  
S. Nakano ◽  
Y. Kuwano
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Potential Role ◽  
Dangling Bonds ◽  
Energy Distributions ◽  
Soaking Time ◽  
Narrow Component ◽  
Annealing Conditions ◽  
Broad Component ◽  
Spin Resonance

ABSTRACTTransient light-induced electron spin resonance (LESR) at 120 K, has been used to investigate deep defects in a-Si:H through changes in the lineshape. When the lineshape is deconvoluted into narrow and broad components, the narrow component is found to decrease, relative to the broad component, with increasing light-soaking time. Similar changes are not observed, however, in as-deposited or annealed films regardless of deposition and annealing conditions. An important role for charged dangling bonds is proposed to explain these changes and we suggest that intrinsic (stable) and light-induced (metastable) defects play different roles in transient-LESR and may occupy different energy distributions in the gap.

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