scholarly journals Local Group Velocity from the PSCz and BTP Surveys

2004 ◽  
Vol 21 (4) ◽  
pp. 415-417 ◽  
Author(s):  
Kenton J. D'Mellow ◽  
Will Saunders ◽  
Keyword(s):  
Group Velocity ◽  
Systematic Uncertainty ◽  
Local Group ◽  
Galactic Plane ◽  
Significant Component ◽  
Preliminary Results ◽  
Gravitational Pull

AbstractWe present a brief overview and preliminary measure of the Local Group velocity, using the PSCz survey together with its recently completed extension into the Galactic plane, the Behind The Plane (BTP) survey. The addition of the BTP has increased the total sky coverage from 84% to 93%, drastically reducing the systematic uncertainty in the direction of the local gravitational pull caused by incomplete sky coverage. We present methods that self-consistently determine the acceleration in the presence of redshift distortions. Preliminary results suggest that the dipole converges within the survey limiting depth. There is a large, but only marginally significant, component to the dipole arising at 180–200 h–1 Mpc.

scholarly journals I.—Secular Earth-Creep

1909 ◽  
Vol 6 (4) ◽  
pp. 145-148 ◽  
Author(s):  
E. H. L. Schwarz
Keyword(s):  
South Africa ◽  
Diurnal Variation ◽  
Royal Society ◽  
The Sun ◽  
Special Design ◽  
Important Paper ◽  
Preliminary Results ◽  
Gravitational Pull ◽  
Set Up ◽  
Horizontal Pendulum

Dr. J. R. Sutton has recently read a most important paper to the Royal Society of South Africa on the diurnal variation of level at Kimberley. The paper gave the preliminary results of observations made during the course of three years upon the variation of the level of the ground as recorded by a large horizontal pendulum of a special design made for the author by the Cambridge Instrument Company. It appeared from the results that the movements in the surface of the ground, which set up corresponding movements in the pendulum, were very great. The maximum westerly elongation of the extremity of the pendulum occurred about 5.30 a.m., the maximum easterly about 4.15 p.m., the medium positions a little before 11 a.m. and 9.30 p.m. Geometrically these movements may be represented on the hypothesis that the hemisphere facing the sun bulges out, forming a sort of meniscus to the geosphere. The rise and fall of the surface of the ground which such a supposition would postulate is enormous, and the very magnitude has led Dr. Sutton to hesitate in giving the figures. There can, however, be very little doubt that some rise and fall in the earth's surface is occasioned by the sun's gravitational pull, although the present figures may have to be lessened by taking into consideration other causes which contribute to the disturbance of the pendulum.

Chemical composition of globular clusters in dwarf galaxies

2019 ◽  
Vol 14 (S351) ◽  
pp. 317-320
Author(s):  
Søren S. Larsen
Keyword(s):  
Chemical Composition ◽  
Globular Clusters ◽  
Milky Way ◽  
Local Group ◽  
Dwarf Galaxies ◽  
Chemical Abundances ◽  
Preliminary Results ◽  
Detailed Chemical

AbstractThis contribution gives an update on on-going efforts to characterise the detailed chemical abundances of Local Group globular clusters (GCs) from integrated-light spectroscopy. Observations of a sample of 20 GCs so far, located primarily within dwarf galaxies, show that at low metallicities the [α/Fe] ratios are generally indistinguishable from those in Milky Way GCs. However, the “knee” above which [α/Fe] decreases towards Solar-scaled values occurs at lower metallicities in the dwarfs, implying that GCs follow the same trends seen in field stars. Efforts are underway to establish NLTE corrections for integrated-light abundance measurements, and preliminary results for Mn are discussed.

Preliminary results of the Spacelab-2 infrared telescope survey of the galactic plane at 2.4μm

1987 ◽  
Author(s):  
G. J. Melnick ◽  
G. G. Fazio ◽  
D. G. Koch ◽  
G. H. Rieke ◽  
E. T. Young ◽  
...  
Keyword(s):  
Galactic Plane ◽  
Preliminary Results ◽  
Infrared Telescope

scholarly journals H I Emission and Absorption in the Southern Galactic Plane Survey

2001 ◽  
Vol 18 (1) ◽  
pp. 84-90 ◽  
Author(s):  
N. M. McClure-Griffiths ◽  
John M. Dickey ◽  
B. M. Gaensler ◽  
A. J. Green ◽  
R. F. Haynes ◽  
...  
Keyword(s):  
Power Spectrum ◽  
Radio Telescope ◽  
Large Scale ◽  
Galactic Plane ◽  
Pilot Project ◽  
Small Scale ◽  
Preliminary Results ◽  
Test Region ◽  
Scale Structures ◽  
Spatial Power Spectrum

AbstractWe present preliminary results from the Southern Galactic Plane Survey (SGPS) Test Region and Parkes data. As part of the pilot project for the Southern Galactic Plane Survey, observations of a Test Region (325·5° ≤l ≤ 333·5°; −0·5° ≤ b ≤ 3·5°) were completed in December 1998. Single-dish observations of the full survey region (253° ≤ l ≤ 358 ° |b| ≤ 1°) with the Parkes Radio Telescope were completed in March 2000. We present a sample of SGPS H I data, with particular attention to the smallest-and largest-scale structures seen in absorption and emission, respectively. On the large scale, we detect many prominent H I shells. On the small scale, we note extremely compact, cold clouds seen in H I self-absorption. We explore how these two classes of objects probe opposite ends of the H I spatial power spectrum.

scholarly journals Imaging of selected sources from the Methanol Multibeam Survey

2007 ◽  
Vol 3 (S242) ◽  
pp. 184-185
Author(s):  
D. Wong-McSweeney ◽  
G. A. Fuller ◽  
S. Etoka
Keyword(s):  
Angular Resolution ◽  
Galactic Plane ◽  
High Angular Resolution ◽  
Maser Emission ◽  
Methanol Maser ◽  
Preliminary Results ◽  
Methanol Masers ◽  
Maser Sources

AbstractHigh angular resolution observations are essential for understanding the nature of maser emission and the sources which excite it. Here we present preliminary results from MERLIN observations of three methanol masers from the Toruń survey. These MERLIN observations are being analysed as part of the interferometric component of the Methanol Multibeam (MMB) Survey which is surveying the Galactic plane at |b|≤2° for 6.67 GHz methanol maser sources.

scholarly journals The Tully-Fisher Relation and its Application to the Distance Scale

1983 ◽  
Vol 6 ◽  
pp. 269-282 ◽  
Author(s):  
M. Aaronson
Keyword(s):  
Group Velocity ◽  
Deceleration Parameter ◽  
Local Group ◽  
Hubble Constant ◽  
Distance Scale ◽  
Expansion Rate ◽  
Distance Indicator ◽  
Fisher Relation ◽  
Hubble Flow ◽  
Local Value

AbstractThe Tully-Fisher relation applied in the infrared appears to be the best global distance indicator presently available for determining the expansion rate and deviations from uniform Hubble flow. In this article recent results obtained using the IR/H I method are reviewed. A Virgo-directed Local Group velocity of about 300 km s–1 is indicated (implying a local value for the deceleration parameter qo ~ 0.05 – 0.1) along with a “best guess” value for the Hubble Constant of 85 km s-1 Mpc-1.

scholarly journals A New High-Resolution Optical Study of Halo Gas

1989 ◽  
Vol 120 ◽  
pp. 442-447
Author(s):  
C. E. Albert ◽  
J. C. Blades ◽  
D. C. Morton ◽  
M. Proulx ◽  
F. J. Lockman
Keyword(s):  
High Resolution ◽  
Galactic Plane ◽  
Optical Study ◽  
Interstellar Gas ◽  
Preliminary Results ◽  
Halo Gas

Abstract:We present preliminary results from a new high resolution optical study of halo gas at the coudé focus of the Canada - France - Hawaii Telescope. Our work is still in progress so two general results are presented here: significant absorption is produced in interstellar gas beyond 500 pc from the galactic plane, and well-resolved halo clouds are identified.

scholarly journals An Infrared Survey of Galactic Supernova Remnants

1988 ◽  
Vol 101 ◽  
pp. 379-382
Author(s):  
Richard G. Arendt
Keyword(s):  
Data Base ◽  
Supernova Remnants ◽  
Galactic Plane ◽  
Spectral Characteristics ◽  
Cassiopeia A ◽  
Preliminary Results ◽  
Infrared Astronomical Satellite ◽  
Astronomical Satellite ◽  
Infrared Survey

AbstractPresented here are preliminary results from a survey of supernova remnants (SNRs) in the data base collected by the Infrared Astronomical Satellite (IRAS). About one-third of the known galactic SNRs are visible in the IRAS data. Confusion with other sources in the galactic plane prohibits the detection of many remnants. The objects that are detected have similar spectral characteristics and temperatures, except that the three youngest remnants known, Tycho, Kepler, and Cassiopeia A, are distinctly warmer.

scholarly journals A 10-Ghz radio-continuum survey of the Galactic–plane region at the Nobeyama Radio Observatory - A complex region at ℓ = 22° − 25°

1985 ◽  
Vol 106 ◽  
pp. 323-324
Author(s):  
Y. Sofue ◽  
H. Hirabayashi ◽  
K. Akabane ◽  
M. Inoue ◽  
T. Handa ◽  
...  
Keyword(s):  
Galactic Plane ◽  
Extensive Study ◽  
Radio Continuum ◽  
Plane Region ◽  
Radio Observatory ◽  
Complex Region ◽  
Preliminary Results

Preliminary results of a 10-GHz radio-continuum survey of the galactic-plane region using the 45-m telescope at NRO are presented. An extensive study of a complex region at 22° ≦ ℓ ≦ 25°, |b|≳1° has been made.

scholarly journals The Galactic distribution of Wolf-Rayet stars: an optical and infrared approach

2003 ◽  
Vol 212 ◽  
pp. 441-450 ◽  
Author(s):  
Karel A. van der Hucht
Keyword(s):  
Surface Density ◽  
Local Group ◽  
Galactic Center ◽  
Solar Neighborhood ◽  
Galactocentric Distance ◽  
Preliminary Results ◽  
Number Ratio ◽  
Photometric Distance ◽  
Galactic Distribution

The recent VIIth Catalogue of Galactic Wolf-Rayet Stars (van der Hucht 2001), lists 227 Population I WR stars, comprising 127 WN, 87 WC, 10 WN/WC and 3 WO stars. Additional discoveries since then bring the census to ≳ 253 WR stars, including ≳ 27 WNL and 13 WCL stars within 50 pc of the Galactic Center. A re-determination of the optical photometric distances and the galactic distribution of WR stars shows in the solar neighbourhood (d < 3 kpc) a projected surface density of 2.7 WR stars per kpc2, a NWC/NWN number ratio of 1.3, and a WR binary frequency of 40%. Compared with other Local Group galaxies, the NWC/NWN number ratio in the solar neighborhood is a factor ~2 above the observed metallicity-dependent trend. This could imply that some 30 galactic WN stars in the d < 3 kpc volume are still hiding. Preliminary results of infrared photometric distance determinations are shown. The galactocentric distance (RWR) distribution per subtype shows RWN and RWC decreasing with later WN and WC subtypes. The observed trend is more indicative of WNE → WCE and WNL → WCL subtype evolution than of WNL → WNE and WCL → WCE subtype evolution.

Sign in / Sign up

Export Citation Format

Share Document