Luminosity Distance, Angular Size and Surface Brightness in Cosmological General Relativity

2007 ◽  
Vol 37 (3) ◽  
pp. 446-454 ◽  
Author(s):  
John G. Hartnett ◽  
Firmin J. Oliveira
Keyword(s):  
General Relativity ◽  
Surface Brightness ◽  
Angular Size ◽  
Luminosity Distance

NGC 2899: An Evolved Bipolar Planetary Nebula

1989 ◽  
Vol 131 ◽  
pp. 179-179
Author(s):  
J. A. López ◽  
L. H. Falcón ◽  
M. T. Ruiz ◽  
M. Roth
Keyword(s):  
Planetary Nebula ◽  
Surface Brightness ◽  
High Surface ◽  
Angular Size ◽  
Minor Axis ◽  
Bipolar Structure ◽  
High Surface Brightness ◽  
Central Object ◽  
Toroidal Geometry

NGC 2899 (PK 277-3°l, He 2-30, RCW 43) is a southern planetary nebula of fairly large angular size (∼2!6 × 1!4) and moderate high surface brightness. Its morphology strongly resembles a loose bipolar structure with conspicuous bright condensations of toroidal geometry placed along the minor axis, on each side of the central object.

scholarly journals Measuring the GC luminosity function up to z ~ 0.2

2009 ◽  
Vol 5 (S266) ◽  
pp. 351-351
Author(s):  
K. A. Alamo-Martínez ◽  
R. A. González-Lópezlira ◽  
J. Blakeslee
Keyword(s):  
Galaxy Formation ◽  
Globular Clusters ◽  
Surface Brightness ◽  
Luminosity Function ◽  
Elliptical Galaxy ◽  
Angular Size ◽  
Spectroscopic Studies ◽  
Stellar Systems ◽  
Surface Brightness Fluctuations ◽  
Specific Frequency

AbstractGlobular clusters (GCs) are stellar systems (~106 M⊙) with very regular symmetry, single age, and single metallicity. Spectroscopic studies have revealed very old ages, suggesting that GCs were formed in the earliest stages of galaxy formation and assembly. The aim of this work is to find out how far we can measure the GC luminosity function, specific frequency, and radial distribution, applying the surface-brightness-fluctuations (SBF) technique to deep ACS images. To this end, we apply the effects caused by higher redshift to HST/ACS images (in two optical bands, F606W and F814W) of M87, an elliptical galaxy with a very well-studied GC system. The effects involved are: (i) evolution, (ii) inverse k correction, (iii) binning of the image to smaller angular size, (iv) cosmological dimming of surface brightness, and (v) noise addition to account for different exposure times. After processing the images we detect the brightest GCs through direct photometry (e.g., with SExtractor), whereas the unresolved clusters are measured through SBFs. The above treatment is repeated for z=0.05, 0.1, 0.14, and 0.18, and the results are compared to the measurements at z=0 to estimate biases and incompleteness.

The Angular Size of the Cepheid Carinae: A Comparison of the Interferometric and Surface Brightness Techniques

2004 ◽  
Vol 604 (2) ◽  
pp. L113-L116 ◽  
Author(s):  
Pierre Kervella ◽  
Pascal Fouqu ◽  
Jesper Storm ◽  
Wolfgang P. Gieren ◽  
David Bersier ◽  
...  
Keyword(s):  
Surface Brightness ◽  
Angular Size

scholarly journals BiGONLight: light propagation with bi-local operators in Numerical Relativity

2021 ◽  
Author(s):  
Michele Grasso ◽  
Eleonora Villa
Keyword(s):  
General Relativity ◽  
Light Propagation ◽  
Numerical Relativity ◽  
Luminosity Distance ◽  
Test Bed ◽  
Angular Diameter Distance ◽  
Redshift Drift ◽  
Local Operators ◽  
Dust Universe ◽  
New Framework

Abstract BiGONLight, Bilocal Geodesic Operators framework for Numerical Light propagation, is a new tool for light propagation in Numerical Relativity. The package implements the Bi-local Geodesic Operators formalism, a new framework for light propagation in General Relativity. With BiGONLight it is possible to extract observables such as angular diameter distance, luminosity distance, magnification as well as new real-time observables like parallax and redshift drift within the same computation. As a test-bed for our code we consider two exact cosmological models, the ΛCDM and the inhomogeneous Szekeres model, and a simulated dust universe. All our tests show an excellent agreement with known results.

scholarly journals Cosmology Under Milne's Shadow

2005 ◽  
Vol 22 (3) ◽  
pp. 287-291 ◽  
Author(s):  
Michał J. Chodorowski
Keyword(s):  
General Relativity ◽  
Cosmological Model ◽  
Special Relativity ◽  
Confidence Level ◽  
Reference Model ◽  
Kinematic Model ◽  
Luminosity Distance ◽  
Angular Diameter Distance ◽  
Empty Universe ◽  
Better Than

AbstractBased on the magnitude–redshift diagram for the sample of supernovae Ia analyzed by Perlmutter et al. (1999), Davis & Lineweaver (2004) ruled out the special relativistic interpretation of cosmological redshifts at a confidence level of 23σ. Here, we critically reassess this result. Special relativity is known to describe the dynamics of an empty universe, by means of the Milne kinematic model. Applying only special relativistic concepts, we derive the angular diameter distance and the luminosity distance in the Milne model. In particular, in this model we do not use the underlying metric in its Robertson–Walker form, so our exposition is useful for readers without any knowledge of general relativity. We do however, explicitly use the special relativistic Doppler formula for redshift. We apply the derived luminosity distance to the magnitude–redshift diagram for supernovae Ia of Perlmutter et al. (1999) and show that special relativity fits the data much better than that claimed by Davis & Lineweaver. Specifically, using these data alone, the Milne model is ruled out only at a 2σ level. Alhough not a viable cosmological model, in the context of current research on supernovae Ia it remains a useful reference model when comparing predictions of various cosmological models.

scholarly journals The effect of the cosmological constant on a quadrupole signal in the linearized approximation

2018 ◽  
Vol 27 (02) ◽  
pp. 1850004 ◽  
Author(s):  
László Ábel Somlai ◽  
Mátyás Vasúth
Keyword(s):  
General Relativity ◽  
Cosmological Constant ◽  
Gravitational Wave ◽  
Equations Of Motion ◽  
Luminosity Distance ◽  
Background Term ◽  
Self Consistent ◽  
Linearized Theory

In this study the effects of a nonzero cosmological constant [Formula: see text] on a quadrupole gravitational wave (GW) signal are analyzed. The linearized approximation of general relativity was used, so the perturbed metric can be written as the sum of [Formula: see text] GWs and [Formula: see text] background term, originated from [Formula: see text]. The [Formula: see text] term was also included in this study. To derive physically relevant consequences of [Formula: see text] comoving coordinates are used. In these coordinates, the equations of motion (EoMs) are not self-consistent so the result of the linearized theory has to be transformed to the FRW frame. The luminosity distance and the same order of the magnitude of frequency in accordance with the detected GWs were used to demonstrate the effects of the cosmological constant.

Variation of the amount of hydrogen along the galactic ridge

1967 ◽  
Vol 31 ◽  
pp. 171-172
Author(s):  
Th. Schmidt-Kaler
Keyword(s):  
Surface Brightness ◽  
Milky Way ◽  
Neutral Hydrogen ◽  
Line Of Sight ◽  
Optical Surface ◽  
Hydrogen Density ◽  
Continuous Radiation ◽  
Galactic Longitude

The integralNHof neutral-hydrogen density along the line of sight is determined from the Kootwijk and Sydney surveys. The run ofNHwith galactic longitude agrees well with that of thermal continuous radiation and that of the optical surface brightness of the Milky Way.

Angular size of OH emission regions

1967 ◽  
Vol 31 ◽  
pp. 71-72
Author(s):  
B. F. Burke ◽  
P. P. Crowther ◽  
J. M. Moran ◽  
A. E. E. Rogers ◽  
J. A. Ball ◽  
...  
Keyword(s):  
Angular Size ◽  
Emission Sources ◽  
Ngc 6334

Interferometry gives effective diameters less than 20″ for the OH emission sources in W3and Sgr B2. The sources in W49and NGC 6334 contain two or more components, some of which are smaller than 25″.

Surface Brightness Scale of Galactic Cepheids

1999 ◽  
Vol 190 ◽  
pp. 561-562
Author(s):  
G. P. Di Benedetto
Keyword(s):  
Surface Brightness ◽  
Variable Stars ◽  
Giant Stars ◽  
Near Ir

An accurate calibration of the surface brightness scaleSVas a function of the near-IR color (V–K) has been recently measured for non-variable Galactic dwarf and giant stars. It can be shown that this correlation can be applied to theSVscale of Galactic Cepheid variable stars, which are of major cosmological interest.

Distance to SN 1987A and the LMC

1999 ◽  
Vol 190 ◽  
pp. 549-554
Author(s):  
Nino Panagia
Keyword(s):  
Angular Size ◽  
Large Magellanic Cloud ◽  
Magellanic Cloud ◽  
Light Curves ◽  
Distance Modulus ◽  
Absolute Size ◽  
Sn 1987A

Using the new reductions of the IUE light curves by Sonneborn et al. (1997) and an extensive set of HST images of SN 1987A we have repeated and improved Panagia et al. (1991) analysis to obtain a better determination of the distance to the supernova. In this way we have derived an absolute size of the ringRabs= (6.23 ± 0.08) x 1017cm and an angular sizeR″ = 808 ± 17 mas, which give a distance to the supernovad(SN1987A) = 51.4 ± 1.2 kpc and a distance modulusm–M(SN1987A) = 18.55 ± 0.05. Allowing for a displacement of SN 1987A position relative to the LMC center, the distance to the barycenter of the Large Magellanic Cloud is also estimated to bed(LMC) = 52.0±1.3 kpc, which corresponds to a distance modulus ofm–M(LMC) = 18.58±0.05.

Sign in / Sign up

Export Citation Format

Share Document