306 citations · 2.9k across the 108 of their papers we have counts for
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Late Ordovician geographic patterns of extinction compared with simulations of astrophysical ionizing radiation damage
Adrian L. Melott, Brian C. Thomas
Based on the intensity and rates of various kinds of intense ionizing radiation events such as supernovae and gamma-ray bursts, it is likely that the Earth has been subjected to on…
Atmospheric Consequences of Cosmic Ray Variability in the Extragalactic Shock Model II: Revised ionization levels and their consequences
A. L. Melott, D. Atri, B. C. Thomas +3
It has been suggested that galactic shock asymmetry induced by our galaxy's infall toward the Virgo Cluster may be a source of periodicity in cosmic ray exposure as the solar syste…
Comment on 'Discreteness Effects in Lambda Cold Dark Matter Simulations: A Wavelet-Statistical View' by Romeo et al
Adrian L. Melott
Essential equivalence of the conclusions of Romeo et al. (arXiv:0804.0294v1) with earlier work is pointed out. A possible general explanation for these conclusions is suggested.
Lookup tables to compute high energy cosmic ray induced atmospheric ionization and changes in atmospheric chemistry
Dimitra Atri, Adrian L. Melott, Brian C. Thomas
A variety of events such as gamma-ray bursts and supernovae may expose the Earth to an increased flux of high-energy cosmic rays, with potentially important effects on the biospher…
Comment on 'Discreteness Effects in Simulations of Hot/Warm Dark Matter' by J. Wang & S.D.M. White
Adrian L. Melott
Wang and White (2007) have discussed some problems with N-body simulation methods. These problems are a special case of a more general problem which has been largely unacknowledged…
Superluminous supernovae: No threat from Eta Carinae
Brian C. Thomas, Adrian L. Melott, Brian D. Fields +1
Recently Supernova 2006gy was noted as the most luminous ever recorded, with a total radiated energy of ~10^44 Joules. It was proposed that the progenitor may have been a massive e…
Modeling atmospheric effects of the September 1859 Solar Flare
Brian Thomas, Charles Jackman, Adrian Melott
We have modeled atmospheric effects, especially ozone depletion, due to a solar proton event which probably accompanied the extreme magnetic storm of 1-2 September 1859. We use an…
Fossil Biodiversity: Red Noise Plus Signal
Adrian L. Melott, Bruce S. Lieberman
We have examined the Fourier power spectrum as well as the Hurst exponent of extinction, origination, and total biodiversity in the marine fossil record, using a recently improved…
Comment on: Protecting Life in the Milky Way: Metals Keep the GRBs Away by Stanek et al
Adrian L. Melott
Stanek et al. (astro-ph/0604113) have noted that the four low-redshift long-duration gamma-ray bursts (LSB) observed to date all occurred in faint, metal-poor galaxies. Given this…
Terrestrial Consequences of Spectral and Temporal Variability in Ionizing Photon Events
Larissa M. Ejzak, Adrian L. Melott, Mikhail V. Medvedev +1
Gamma-Ray Bursts (GRBs) directed at Earth from within a few kpc may have damaged the biosphere, primarily though changes in atmospheric chemistry which admit greatly increased Sola…
Do extragalactic cosmic rays induce cycles in fossil diversity?
Mikhail V. Medvedev, Adrian L. Melott
Recent work has revealed a 62 (+/-) 3-million-year cycle in the fossil diversity in the past 542 My, however no plausible mechanism has been found. We propose that the cycle may be…
Gamma-ray bursts and terrestrial planetary atmospheres
Brian C. Thomas, Adrian L. Melott
We describe results of modeling the effects on Earth-like planets of long-duration gamma-ray bursts (GRBs) within a few kiloparsecs. A primary effect is generation of nitrogen oxid…
Gamma-Ray Bursts and the Earth: Exploration of Atmospheric, Biological, Climatic and Biogeochemical Effects
Brian C. Thomas, Adrian L. Melott, Charles H. Jackman +7
Gamma-Ray Bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. We have used a two-dimensional atmospheric model to inve…
Climatic and Biogeochemical Effects of a Galactic Gamma-Ray Burst
Adrian L. Melott, Brian C. Thomas, Daniel P. Hogan +2
It is likely that one or more gamma-ray bursts within our galaxy have strongly irradiated the Earth in the last Gy. This produces significant atmospheric ionization and dissociatio…
Terrestrial Ozone Depletion Due to a Milky Way Gamma-Ray Burst
Brian C. Thomas, Charles H. Jackman, Adrian L. Melott +5
Based on cosmological rates, it is probable that at least once in the last Gy the Earth has been irradiated by a gamma-ray burst in our Galaxy from within 2 kpc. Using a two-dimens…
Ozone Abundance in a Nitrogen-Carbon Dioxide Dominated Terrestrial Paleoatmosphere
B. C. Thomas, A. L. Melott, L. D. Martin +1
We compute the ozone distribution for a model terrestrial paleoatmosphere in which the present oxygen abundance is largely replaced by carbon dioxide, which we argue is a reasonabl…
Optimal Moments for Velocity Fields Analysis
Hume A Feldman, Richard Watkins, Adrian Melott +1
We describe a new method of overcoming problems inherent in peculiar velocity surveys by using data compression as a filter with which to separate large-scale, linear flows from sm…
Numerical study of the cosmological velocity field as a function of density
Alvaro Dominguez, Adrian L. Melott
We report on a new study of the velocity distribution in N-body simulations. We investigate the center-of-mass and internal kinetic energies of coarsening cells as a function of ti…
Did a gamma-ray burst initiate the late Ordovician mass extinction?
A. Melott, B. Lieberman, C. Laird +6
Gamma-ray bursts (hereafter GRB) produce a flux of radiation detectable across the observable Universe, and at least some of them are associated with galaxies. A GRB within our own…
Simulated Versus Observed Cluster Eccentricity Evolution
Stephen Floor, Adrian Melott, and Patrick Motl
The rate of galaxy cluster eccentricity evolution is useful in understanding large scale structure. Rapid evolution for 0.13 has been found in two different observed cluster…
Quantifying the Bull's Eye Effect
Brian C. Thomas, Adrian L. Melott, Hume A. Feldman +1
We have used N-body simulations to develop two independent methods to quantify redshift distortions known as the Bull's Eye effect (large scale infall plus small scale virial motio…
Optimal Moments for the Analysis of Peculiar Velocity Surveys II: Testing
Hume A. Feldman, Richard Watkins, Adrian L. Melott +1
Analyses of peculiar velocity surveys face several challenges, including low signal--to--noise in individual velocity measurements and the presence of small--scale, nonlinear flows…
Limits on thermal conduction in galaxy clusters
Mikhail V. Medvedev, Adrian L. Melott, Chris Miller +1
We have calculated lower limits for the global effective thermal conductivity in a sample of 165 Abell clusters. We assumed that cluster X-ray luminosity is compensated by a conduc…
Eccentricity Evolution in Simulated Galaxy Clusters
Stephen Floor, Adrian Melott, Christopher Miller +1
Strong cluster eccentricity evolution for has appeared in a variety of observational data sets. We examine the evolution of eccentricity in simulated galaxy clusters u…