scholarly journals Subparsec-scale HI in the Nucleus of NGC 4151

2001 ◽  
Vol 205 ◽  
pp. 192-193
Author(s):  
C.G. Mundell ◽  
J.M. Wrobel ◽  
A. Pedlar ◽  
J.F. Gallimore
Keyword(s):  
High Resolution ◽  
Ngc 4151 ◽  
Continuum Image ◽  
The Continuum

We present sensitive, high-resolution λ21-cm VLBA+VLA observations of the radio jet and nuclear HI absorption in NGC 4151. The 25-mas (1.6-pc) resolution continuum image reveals a highly collimated radio jet, underlying the discrete components seen previously with MERLIN and the VLA. Spatially and kinematically complex HI absorption is detected against the whole 3-pc extent of the continuum component predicted by Ulvestad et al. to contain the AGN. Instead, we suggest the component against which the absorption is detected is part of the eastern counterjet, ruling it out as the location for the AGN.

High-resolution spectroscopy near the continuum limit: the microwave spectrum of trans-3-bromo-1,1,1,2,2-pentafluoropropane

2018 ◽  
Vol 117 (9-12) ◽  
pp. 1351-1359 ◽  
Author(s):  
Frank E. Marshall ◽  
Nicole Moon ◽  
Thomas D. Persinger ◽  
David J. Gillcrist ◽  
Nelson E. Shreve ◽  
...  
Keyword(s):  
High Resolution ◽  
Continuum Limit ◽  
Microwave Spectrum ◽  
High Resolution Spectroscopy ◽  
The Continuum

Ultraviolet, Optical and X-Ray Monitoring of the Continuum of NGC 4151

1981 ◽  
pp. 119-122
Author(s):  
G. C. Perola ◽  
A. Boksenberg ◽  
G. E. Bromage ◽  
J. Clavel ◽  
M. Elvis ◽  
...  
Keyword(s):  
X Ray ◽  
Ngc 4151 ◽  
The Continuum

The nature of flux variations in the continua and broad-line regions of selected active galactic nuclei

2020 ◽  
Vol 496 (1) ◽  
pp. 784-800
Author(s):  
A Bewketu Belete ◽  
L J Goicoechea ◽  
B L Canto Martins ◽  
I C Leão ◽  
J R De Medeiros
Keyword(s):  
Active Galactic Nuclei ◽  
Moving Average ◽  
Sampling Rate ◽  
Galactic Nuclei ◽  
Small Sample ◽  
Light Curves ◽  
Ngc 4151 ◽  
The Given ◽  
Ngc 7469 ◽  
The Continuum

ABSTRACT We present a multifractal analysis of the long-term light curves of a small sample of type 1 active galactic nuclei: NGC 4151, Arp 102B, 3C 390.3, E1821+643 and NGC 7469. We aim to investigate how the degrees of multifractality of the continuum and Hβ line vary among the five different objects and to check whether the multifractal behaviours of the continuum and the Hβ line correlate with standard accretion parameters. The backward (θ  = 0) one-dimensional multifractal detrended moving average procedure was applied to light curves covering the full observation period and partial observation periods containing an equal number of epochs for each object. We detected multifractal signatures for the continua of NGC 4151, Arp 102B and 3C 390.3 and for the Hβ lines of NGC 4151 and 3C 390.3. However, we found nearly monofractal signatures for the continua of E1821+643 and NGC 7469, as well as for the Hβ lines of Arp 102B, E1821+643 and NGC 7469. In addition, we did not find any correlations between the degree of multifractality of the Hβ line and accretion parameters, while the degree of multifractality of the continuum seems to correlate with the Eddington ratio (i.e. the smaller the ratio is, the stronger the degree of multifractality). The given method is not robust, and these results should be taken with caution. Future analysis of the sampling rate and other properties of the light curves should help with better constraining and understanding these results.

A Discussion on solar studies with special reference to space observations - A high resolution solar ultraviolet spectrum between 200 and 220 nm

1971 ◽  
Vol 270 (1202) ◽  
pp. 29-46 ◽  
Keyword(s):  
High Resolution ◽  
Solar Spectrum ◽  
Ultraviolet Spectrum ◽  
Absorption Feature ◽  
Intensity Analysis ◽  
Echelle Spectrograph ◽  
Broad Absorption ◽  
First Time ◽  
Solar Ultraviolet ◽  
The Continuum

A high resolution solar spectrum in the range 200 to 220 nm has been recorded with an echelle spectrograph launched in, a sun-pointing Skylark rocket. The data have been reduced and are presented as intensity-wavelength plots together with a wavelength list and proposed identifications. A broad absorption feature at 212.4 nm is assigned to a single source and an intensity analysis confirms this to be the non-resonance Sii line at 212.412 nm. The discontinuity in the continuum intensity near 208.7 nm is revealed with high resolution for the first time and is assigned to the photoionization edge of A11. An analysis shows that its intensity drop and wavelength position can only be explained by adjustments to the solar model in the region 0.001 < T 5000 < 0.2.

scholarly journals Massive Star Formation in W49

1987 ◽  
Vol 115 ◽  
pp. 143-145
Author(s):  
J. Dreher ◽  
S. Vogel ◽  
S. Terebey ◽  
W. J. Welch
Keyword(s):  
Star Formation ◽  
High Resolution ◽  
Massive Star ◽  
Hii Regions ◽  
Molecular Line ◽  
The Galaxy ◽  
Molecular Lines ◽  
H Ii Region ◽  
Scale Structures ◽  
The Continuum

W49 is the most luminous H II region complex in the galaxy. VLA maps in the continuum reveal a complex of more than two dozen compact HII regions, including a ring-like distribution of a dozen such regions within a volume of 1 pc. In addition to the VLA maps, we have obtained high resolution maps in this field with the Hat Creek Millimeter Interferometer in the following molecular lines: HCO+(1-0), H13CO+(1-0), SiO(v = 0, J = 2-1), SiO(v = 1, J = 2-1), H13CN(1-0), HC15N(1-0), SO2 [8(3,5)-9(2,8)], SO2[8(1,7)-8(0,8)], SO[2(2)-1(1)], and CH3CH2CN[10(1,10)-9(1,9)], all near 3 mm wavelengh. These maps will be discussed. The HCO+distribution corresponds to the larger scale structures observed in the continuum maps. In contrast the SO and SiO sources are quite compact. Using the detailed molecular line results obtained in the ORION/KL region as a guide, we are able to identify these latter sources as regions in which the star formation is at an earlier stage, regions where there are outflows.

scholarly journals Gas dynamics in the barred Seyfert galaxy NGC 4151 -- II. High-resolution HI study

1999 ◽  
Vol 304 (3) ◽  
pp. 481-494 ◽  
Author(s):  
C. G. Mundell ◽  
A. Pedlar ◽  
D. L. Shone ◽  
A. Robinson
Keyword(s):  
High Resolution ◽  
Gas Dynamics ◽  
Seyfert Galaxy ◽  
Ngc 4151

scholarly journals Chandra High Resolution Imaging of NGC 1365 and NGC 4151

2010 ◽  
Author(s):  
Junfeng Wang ◽  
G. Fabbiano ◽  
M. Elvis ◽  
G. Risaliti ◽  
M. Karovska ◽  
...  
Keyword(s):  
High Resolution ◽  
High Resolution Imaging ◽  
Ngc 4151 ◽  
Resolution Imaging ◽  
Ngc 1365

scholarly journals High resolution observations of molecular emission lines toward the CI Tau proto-planetary disc: planet-carved gaps or shadowing?

2020 ◽  
Author(s):  
Giovanni P Rosotti ◽  
John D Ilee ◽  
Stefano Facchini ◽  
Marco Tazzari ◽  
Richard A Booth ◽  
...  
Keyword(s):  
High Resolution ◽  
Surface Density ◽  
Morphological Study ◽  
Emission Lines ◽  
Continuum Emission ◽  
Gas Emission ◽  
The Third ◽  
Chemical Effects ◽  
Transfer Modelling ◽  
The Continuum

Abstract Recent observations have revealed that most proto-planetary discs show a pattern of bright rings and dark gaps. However, most of the high-resolution observations have focused only on the continuum emission. In this Paper we present high-resolution ALMA band 7 (0.89mm) observations of the disc around the star CI Tau in the 12CO & 13CO J = 3–2 and CS J = 7–6 emission lines. Our recent work demonstrated that the disc around CI Tau contains three gaps and rings in continuum emission, and we look for their counterparts in the gas emission. While we find no counterpart of the third gap and ring in 13CO, the disc has a gap in emission at the location of the second continuum ring (rather than gap). We demonstrate that this is mostly an artefact of the continuum subtraction, although a residual gap still remains after accounting for this effect. Through radiative transfer modelling we propose this is due to the inner disc shadowing the outer parts of the disc and making them colder. This raises a note of caution in mapping high-resolution gas emission lines observations to the gas surface density – while possible, this needs to be done carefully. In contrast to 13CO, CS emission shows instead a ring morphology, most likely due to chemical effects. Finally, we note that 12CO is heavily absorbed by the foreground preventing any morphological study using this line.

scholarly journals What Geoscience Experts And Novices Look At, And What They See, When Viewing Data Visualizations

2016 ◽  
Vol 3 (1) ◽  
pp. 27 ◽  
Author(s):  
Kim A. Kastens ◽  
Thomas F. Shipley ◽  
Alexander P. Boone ◽  
Frances Straccia
Keyword(s):  
High Resolution ◽  
Eye Tracking ◽  
Data Visualization ◽  
Gaze Direction ◽  
Exploration Time ◽  
Wide Range ◽  
Tracking Behavior ◽  
Data Visualizations ◽  
Shaded Relief ◽  
The Continuum

This study examines how geoscience experts and novices make meaning from an iconic type of data visualization: shaded relief images of bathymetry and topography.  Participants examined, described, and interpreted a global image, two high-resolution seafloor images, and 2 high-resolution continental images, while having their gaze direction eye-tracked and their utterances and gestures videoed. In addition, experts were asked about how they would coach an undergraduate intern on how to interpret this data.  Not unexpectedly, all experts were more skillful than any of the novices at describing and explaining what they were seeing.  However, the novices showed a wide range of performance.  Along the continuum from weakest novice to strongest expert, proficiency developed in the following order: making qualitative observations of salient features, making simple interpretations, making quantitative observations.  The eye-tracking analysis examined how the experts and novices invested 20 seconds of unguided exploration, after the image came into view but before the researcher began to ask questions.  On the cartographic elements of the images, experts and novices allocated their exploration time differently:  experts invested proportionately more fixations on the latitude and longitude axes, while students paid more attention to the color bar.  In contrast, within the parts of the image showing the actual geomorphological data, experts and novices on average allocated their attention similarly, attending preferentially to the geologically significant landforms.   Combining their spoken responses with their eye-tracking behavior, we conclude that the experts and novices are looking in the same places but “seeing” different things.

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