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991.
A set of well-measured, {low-z}, type Ia supernovae from the Calán/Tololo SNe data sets is used to determine benchmark parameters
in our hydrodynamics-based, light-curve model. The light-curve data fit fairly well in B, V, and R passbands but not as well
in the I passband. The fitting procedure, extracted best-fit model parameters, and their connection to type Ia SN parameters
are presented. Our benchmarked light-curve model represents an alternative to empirical template methods for the analysis
of light-curve data. 相似文献
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D. Heath Jones Will Saunders Matthew Colless Mike A. Read Quentin A. Parker Fred G. Watson Lachlan A. Campbell Daniel Burkey Thomas Mauch Lesa Moore Malcolm Hartley Paul Cass Dionne James Ken Russell Kristin Fiegert John Dawe John Huchra Tom Jarrett Ofer Lahav John Lucey Gary A. Mamon Dominique Proust Elaine M. Sadler Ken-ichi Wakamatsu 《Monthly notices of the Royal Astronomical Society》2004,355(3):747-763
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998.
Using high-quality Hα images of five spiral galaxies, we have studied the luminosity and distribution of the emission from diffuse ionized gas
(DIG). The estimated DIG luminosities account for 25–60%of the total Hα emission in each galaxy and analysis of the distribution has shown that the DIG is highly correlated geometrically with the
most luminous HII regions of the galaxies. The power required to ionize the DIG is very high. The mean ionization rates per
unit surface area of a galaxy disc are of the order of 107 cm-2 s-1. Lyman continuum photons (Lyc) from OB asociations are the most probable sources of this ionization. Here we propose a specific
model for these sources: we show that the Lyman photon flux that leaks out of the density-bounded HII regions of the galaxies
is more than enough to ionize the measured DIG in the five galaxies analysed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
Richard De Grijs Robert W. O'Connell John S. Gallagher III 《Astrophysics and Space Science》2001,276(2-4):397-404
We present high-resolution optical and near-infrared HST observations of two adjacent regions in the fossil starburst region
inM82, M82 B1 and B2. The presence of both the active and the fossil starburst in M82 provides a unique physical environment
to study the stellar and dynamical evolution of star cluster systems. The cluster population in B2 is more heavily affected
by internal extinction than that in B1, amounting to an excess extinction in B2 of AV,excess≃1.1±0.3 mag. Preliminary age estimates date the cluster population in the fossil starburst between ∼2× 108 and ∼ 109 years. The radial luminosity profiles of the brightest clusters are more closely approximated by power laws than by a Gaussian
model, in particular in their wings, which favours a slow star formation scenario.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
1000.
The 2dF Galaxy Redshift Survey: the bJ -band galaxy luminosity function and survey selection function
Peder Norberg Shaun Cole Carlton M. Baugh Carlos S. Frenk Ivan Baldry Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Nicholas J. G. Cross Gavin Dalton Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Ofer Lahav Ian Lewis Stuart Lumsden Steve Maddox Darren Madgwick John A. Peacock Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2002,336(3):907-931