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Cosmological distance indicators [PDF]

open access: yesSpace Science Reviews, 2018
We review three distance measurement techniques beyond the local universe: (1) gravitational lens time delays, (2) baryon acoustic oscillation (BAO), and (3) HI intensity mapping.
A. Agnello   +166 more
core   +8 more sources

Extreme Quasars as Distance Indicators in Cosmology [PDF]

open access: yesFrontiers in Astronomy and Space Sciences, 2020
Quasars accreting matter at very high rates (known as extreme Population A [xA] quasars, possibly associated with super-Eddington accreting massive black holes) may provide a new class of distance indicators covering cosmic epochs from present day up to ...
Deborah Dultzin   +10 more
doaj   +7 more sources

Young and Intermediate-age Distance Indicators [PDF]

open access: yesSpace Science Reviews, 2017
Distance measurements beyond geometrical and semi-geometrical methods, rely mainly on standard candles. As the name suggests, these objects have known luminosities by virtue of their intrinsic proprieties and play a major role in our understanding of ...
A. Bhardwaj   +212 more
core   +5 more sources

Gamma-Ray Bursts as Distance Indicators by a Statistical Learning Approach [PDF]

open access: yesThe Astrophysical Journal Letters
Gamma-ray bursts (GRBs) can be probes of the early Universe, but currently, only 26% of GRBs observed by the Neil Gehrels Swift Observatory have known redshifts ( z ) due to observational limitations.
Maria Giovanna Dainotti   +8 more
doaj   +2 more sources

The development of accessibility indicators for distance learning programs [PDF]

open access: yesResearch in Learning Technology, 2006
A study was undertaken to explore program policies and practices related to the accessibility of American distance learning courses to qualified students with disabilities.
Sheryl Burgstahler
doaj   +4 more sources

K-band versus I-band Surface Brightness Fluctuations as distance indicators [PDF]

open access: bronze, 2001
We evaluate the method of optical and infrared Surface Brightness Fluctuations (SBF) as a distance indicator and its application on 8-m class telescopes, such as the Very Large Telescope (VLT).
Ajhar   +44 more
core   +4 more sources

SALT2: using distant supernovae to improve the use of type Ia supernovae as distance indicators [PDF]

open access: bronze, 2007
We present an empirical model of Type Ia supernovae spectro-photometric evolution with time. The model is built using a large data set including light-curves and spectra of both nearby and distant supernovae, the latter being observed by the SNLS ...
J. Guy   +24 more
openalex   +3 more sources

Astronomical Distance Determination in the Space Age: Secondary Distance Indicators [PDF]

open access: green, 2018
The formal division of the distance indicators into primary and secondary leads to difficulties in description of methods which can actually be used in two ways: with, and without the support of the other methods for scaling.
A. Cavaliere   +382 more
core   +6 more sources

Type II supernovae as distance indicators at near-IR wavelengths [PDF]

open access: bronzeMonthly notices of the Royal Astronomical Society, 2018
Motivated by the advantages of observing at near-IR wavelengths, we investigate Type II supernovae (SNe II) as distance indicators at those wavelengths through the Photospheric Magnitude Method (PMM).
Ósmar Rodríguez   +15 more
openalex   +3 more sources

GIS modeling of seismic vulnerability of residential fabrics considering geotechnical, structural, social and physical distance indicators in Tehran using multi-criteria decision-making techniques [PDF]

open access: gold, 2015
. The main issue in determining seismic vulnerability is having a comprehensive view of all probable damages related to earthquake occurrence. Therefore, taking into account factors such as peak ground acceleration at the time of earthquake occurrence ...
Fatemeh Rezaie, Mahdi Panahi
openalex   +2 more sources

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