Meiksin's research has concentrated largely on aspects of extra-galactic
astronomy and cosmology. His principal interests are the structure of the
Intergalactic Medium (the baryons left over from the Big Bang that didn't
make galaxies) and the Large-Scale Structure of the Universe. He is also a
Participant of the Sloan Digital Sky Survey , and maintains a
keen interest in the science that may be achieved with LOFAR and an envisioned Square Kilometre Array .
Meiksin coordinates the Edinburgh Centre for Computational Astrophysics. |
Observations of intervening absorption lines in quasar spectra at redshifts
up to z = 6 provide invaluable insight into the primordial density fluctuation
spectrum and the chemical composition of some of the earliest formed
cosmological structures, as well as of the UV background that ionizes them.
Both the Lyman-α forest and the metal absorption systems are sensitive
probes of the epochs of galaxy formation, reionization, reheating, and the
chemical enrichment of the universe. Meiksin and his collaborators have
used numerical simulations of the formation of structure in the IGM to
study the properties of the Lyman-α forest predicted in Cold Dark Matter
dominated cosmologies. The simulations show that the structures giving rise
to the Lyman-α forest span a wide range in morphologies, from sponge-like
to sheet-like to filamentary to spheroidal. Virtually all the baryons in the
Universe are found to be contained in these structures at high redshifts.
For more publications and to learn more about my research on the Lyman-α
forest, click here
for the IGM web pages at the Edinburgh Centre for
Computational Astrophysics.
Measurements of the spectral and spatial structures of the 21-cm line
emission and absorption from HI at high redshifts may provide a means
of probing the epoch of heating of the IGM at 5 < z < 10 and its nature.
With his collaborators, Meiksin has shown how, through a combination
of preheating and radiation, an early generation of sources could excite
21-cm radiation from a warm HI component of the IGM prior to its complete
reionization. The resulting patchwork of 21-cm emission could serve as a
valuable tool for understanding the epoch, nature, and sources of the
reionization of the universe, as well as the morphology of the IGM at early
times. The patchwork may be detectable using the Low Frequency Radio
Array ( LOFAR ) in the Netherlands, or by a Square Kilometre Array
( SKA ).
To learn more about LOFAR , click here
To learn more about the Square Kilometre Array, click
here
For publications and to learn more about the Sloan Digital Sky Survey, click
here