Spatially-resolved evolutionary synthesis modelling of ARP 299: Preliminary results

1989 ◽  
Vol 157 (1-2) ◽  
pp. 117-123 ◽  
Author(s):  
S. A. Stanford
Keyword(s):  
Evolutionary Synthesis ◽  
Preliminary Results ◽  
Spatially Resolved

scholarly journals Preliminary Results on Irradiance Measurements from Lyra and Swap

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
S. T. Kumara ◽  
R. Kariyappa ◽  
M. Dominique ◽  
D. Berghmans ◽  
L. Damé ◽  
...  
Keyword(s):  
High Temporal Resolution ◽  
Preliminary Results ◽  
Spatially Resolved ◽  
Large Yield ◽  
Active Pixel ◽  
Integrated Intensity ◽  
Actual Contribution ◽  
The Individual ◽  
Aluminum Filter ◽  
Full Disk

The first and preliminary results of the photometry of Large Yield Radiometer (LYRA) and Sun Watcher using Active Pixel system detector and Image Processing (SWAP) onboard PROBA2 are presented in this paper. To study the day-to-day variations of LYRA irradiance, we have compared the LYRA irradiance values (observed Sun as a star) measured in Aluminum filter channel (171 Å–500 Å) with spatially resolved full-disk integrated intensity values measured with SWAP (174 Å) and Ca II K 1 Å index values (ground-based observations from NSO/Sac Peak) for the period from 01 April 2010 to 15 Mar 2011. We found that there is a good correlation between these parameters. This indicates that the spatial resolution of SWAP complements the high temporal resolution of LYRA. Hence SWAP can be considered as an additional radiometric channel. Also the K emission index is the integrated intensity (or flux) over a 1 Å band centered on the K line and is proportional to the total emission from the chromosphere; this comparison clearly explains that the LYRA irradiance variations are due to the various magnetic features, which are contributing significantly. In addition to this we have made an attempt to segregate coronal features from full-disk SWAP images. This will help to understand and determine the actual contribution of the individual coronal feature to LYRA irradiance variations.

scholarly journals High Angular Resolution Studies of Stellar Atmospheres

2001 ◽  
Vol 205 ◽  
pp. 288-295 ◽  
Author(s):  
Chris A. Haniff
Keyword(s):  
Angular Resolution ◽  
Stellar Atmospheres ◽  
High Angular Resolution ◽  
Preliminary Results ◽  
Spatially Resolved ◽  
Long Baseline ◽  
Short Baselines ◽  
Limited Sensitivity ◽  
Spatially Resolved Studies

The advent of long-baseline optical and infrared interferometers has meant that spatially resolved studies of stellar atmospheres have now become routinely possible. While prototype arrays, which have typically operated with short baselines and limited sensitivity, have produced exciting preliminary results, it is the development of larger dedicated facility arrays, such as the CHARA, Keck, and VLT interferometers, that offer the best prospects for advancing astrophysics. In this paper I review the possibilities and limitations of interferometric studies of stellar atmospheres, and highlight some recent results from optical/IR spatial interferometry.

scholarly journals BBXRT Observations of Supernova Remnants

1992 ◽  
Vol 9 ◽  
pp. 229-233
Author(s):  
R. Petre ◽  
P. J. Serlemitsos ◽  
F. E. Marshall ◽  
K. Jahoda ◽  
E. A. Boldt ◽  
...  
Keyword(s):  
Spectral Resolution ◽  
Simultaneous Measurement ◽  
Supernova Remnants ◽  
Preliminary Results ◽  
Spatially Resolved ◽  
Spatially Resolved Spectroscopy

AbstractThe BBXRT observed nine supernova remnants during its nine-day flight. We present preliminary results from some of these observations, emphasizing the ability of BBXRT to perform spatially resolved spectroscopy. The improved spectral resolution and efficiency over previous instruments makes possible measurements of previously undetectable lines, and the broad bandpass allows simultaneous measurement of lines from oxygen through iron.

scholarly journals Mapping the structure and source of outflows from star-forming galaxies at z = 2 – 3

2019 ◽  
Vol 15 (S352) ◽  
pp. 268-268
Author(s):  
Bethan James
Keyword(s):  
Absorption Line ◽  
Wavelength Range ◽  
Gravitational Lensing ◽  
Rest Frame ◽  
Uv Spectra ◽  
Star Forming ◽  
Preliminary Results ◽  
Fundamental Properties ◽  
Spatially Resolved

AbstractAs we enter the era of JWST our need to characterise the rest-frame UV spectra of star-forming galaxies becomes essential. By combining the NIR capabilities of JWST with our understanding of UV wavelength science, we have the opportunity to explore fundamental properties of the gas, such as its metallicity and density, as well as the extent, velocity, and magnitude of their outflowing gas, in galaxies out to z ∼ 6. Galaxy outflows in particular play a fundamental role in the evolution of young galaxies at high redshifts, but their properties remain largely unknown as it is difficult to spatially resolve the outflowing gas. To-date, only two attempts to resolve outflows at redshift ∼ 2 have been made using lensing magnification, producing contradictory results on the origin of the outflows. In this talk I will present results from one such groundbreaking study where we combine gravitational lensing with VLT-MUSE to perform one of the first spatially resolved absorption line studies of a galaxy at z = 2 – 3. I will discuss how the the distinct kinematical structure and uniform column densities obtained from the outflowing gas maps reveal ‘global’ rather than ‘locally’ sourced outflows. I will also present preliminary results from our latest attempt to accurately constrain the structure and source of outflows in star-forming galaxies by observing the brightest galaxy-scale lens known with KCWI. I will conclude with the benefits and limitations of spatially resolved observations in this wavelength range, and possible implications on NIRSpec observations of the high-z Universe.

Permeability Profiling of Rock Cores Using a Novel Spatially Resolved NMR Relaxometry Method: Preliminary Results From Sandstone and Limestone

2019 ◽  
Vol 124 (5) ◽  
pp. 4601-4616 ◽  
Author(s):  
Huabing Liu ◽  
Lizhi Xiao ◽  
Fangrong Zong ◽  
Marcel Nogueira d'Eurydice ◽  
Petrik Galvosas
Keyword(s):  
Preliminary Results ◽  
Spatially Resolved ◽  
Nmr Relaxometry ◽  
Rock Cores

Multistatic meteor radar observations to assess the spatial variability of mesospheric/lower thermospheric winds using a 3DVAR+div tomographic retrieval to measure spatially resolved 3D winds 

2021 ◽  
Author(s):  
Gunter Stober ◽  
Alexander Kozlovsky ◽  
Alan Liu ◽  
Zishun Qiao ◽  
Masaki Tsutsumi ◽  
...  
Keyword(s):  
Vertical Wind ◽  
Spatial And Temporal Variability ◽  
Meteor Radar ◽  
Mean Flow ◽  
Radar Observations ◽  
Preliminary Results ◽  
Spatially Resolved ◽  
Wind Variability ◽  
Thermospheric Winds ◽  
Energy And Momentum

<p>The middle atmospheric circulation is driven by atmospheric waves, which carry energy and momentum from their source to the area of their dissipation and thus providing an energetic coupling between different atmospheric layers. A comprehensive understanding of the wave-wave or wave-mean flow interactions often requires a spatial characterization of these waves. Multistatic meteor radar observations provide an opportunity to investigate the spatial and temporal variability of mesospheric/lower thermospheric winds on regional scales. We apply the 3DVAR+div retrievals to observations from the Nordic Meteor Radar Cluster and the Chilean Observation Network De Meteor Radars (CONDOR). Here we present preliminary results of a new 3DVAR+div retrieval to infer the vertical wind variability using spatially resolved observations. The new retrieval includes the continuity equation in the forward model to ensure physical consistency in the vertical winds. Our preliminary results indicate that the vertical wind variability is about +/-2m/s. The 3DVAR+div algorithm provides spatially resolved winds resolves body forces of breaking gravity waves, which are typically indicated by two counterrotating vortices. Furthermore, we infer horizontal wavelength spectra for all 3 wind components to obtain spectral slopes indicating a transition of the vertical to the divergent mode at scales of about 80-120 km at the mesosphere.</p>

The O–C diagrams of minor planets − a new approach to modelling the rotation

1999 ◽  
Vol 173 ◽  
pp. 185-188
Author(s):  
Gy. Szabó ◽  
K. Sárneczky ◽  
L.L. Kiss
Keyword(s):  
Error Analysis ◽  
Time Dependence ◽  
Theoretical Work ◽  
Minor Planet ◽  
Minor Planets ◽  
New Approach ◽  
Preliminary Results ◽  
Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

Cyclic Evolution of Sunspots: Gleaning New Results from Old Data

2000 ◽  
Vol 179 ◽  
pp. 163-165
Author(s):  
S. K. Solanki ◽  
M. Fligge ◽  
P. Pulkkinen ◽  
P. Hoyng
Keyword(s):  
Sunspot Number ◽  
Sunspot Cycle ◽  
Preliminary Results ◽  
Butterfly Diagram

AbstractThe records of sunspot number, sunspot areas and sunspot locations gathered over the centuries by various observatories are reanalysed with the aim of finding as yet undiscovered connections between the different parameters of the sunspot cycle and the butterfly diagram. Preliminary results of such interrelationships are presented.

Systematic effects in observed parallaxes

1978 ◽  
Vol 48 ◽  
pp. 31-35
Author(s):  
R. B. Hanson
Keyword(s):  
Error Estimates ◽  
Zero Point ◽  
Absolute Zero ◽  
Apparent Magnitude ◽  
Coherent System ◽  
Preliminary Results ◽  
General Catalogue ◽  
Systematic Effects ◽  
New Evidence ◽  
Right Ascension

Several outstanding problems affecting the existing parallaxes should be resolved to form a coherent system for the new General Catalogue proposed by van Altena, as well as to improve luminosity calibrations and other parallax applications. Lutz has reviewed several of these problems, such as: (A) systematic differences between observatories, (B) external error estimates, (C) the absolute zero point, and (D) systematic observational effects (in right ascension, declination, apparent magnitude, etc.). Here we explore the use of cluster and spectroscopic parallaxes, and the distributions of observed parallaxes, to bring new evidence to bear on these classic problems. Several preliminary results have been obtained.

Electron Channeling Patterns

1977 ◽  
Vol 35 ◽  
pp. 12-13
Author(s):  
David C. Joy
Keyword(s):  
Electron Diffraction ◽  
Incidence Angle ◽  
Photographic Plate ◽  
Diffraction Effect ◽  
Angle Of Incidence ◽  
Bulk Single Crystal ◽  
Time Resolved ◽  
Electron Channeling ◽  
Spatially Resolved ◽  
Large Bulk

Electron channeling patterns (ECP) were first found by Coates (1967) while observing a large bulk, single crystal of silicon in a scanning electron microscope. The geometric pattern visible was shown to be produced as a result of the changes in the angle of incidence, between the beam and the specimen surface normal, which occur when the sample is examined at low magnification (Booker, Shaw, Whelan and Hirsch 1967).A conventional electron diffraction pattern consists of an angularly resolved intensity distribution in space which may be directly viewed on a fluorescent screen or recorded on a photographic plate. An ECP, on the other hand, is produced as the result of changes in the signal collected by a suitable electron detector as the incidence angle is varied. If an integrating detector is used, or if the beam traverses the surface at a fixed angle, then no channeling contrast will be observed. The ECP is thus a time resolved electron diffraction effect. It can therefore be related to spatially resolved diffraction phenomena by an application of the concepts of reciprocity (Cowley 1969).

Sign in / Sign up

Export Citation Format

Share Document