MY PAPERS
Refereed Journal Articles
This needs to be updated for 2010 and 2011! For now just look up T. M. Davis on ADS!
The WiggleZ Dark Energy Survey: survey design and first data release,
Drinkwater et al. 2009, MNRAS, in press
Our first data release!! This paper is all about the WiggleZ survey and accompanies the release of our database. Check it out at https://wigglez.swin.edu.au/dr1/.
First-year Sloan Digital Sky Survey-II (SDSS-II) supernova results: consistency and constraints with other intermediate-redshift datasets
Lampeitl et al. 2009, MNRAS, in press
The third in our trio of first results papers from the SDSS. This one looked for self-consistency within all the low-redshift data. That is, considering what happens without data from the cosmic microwave background.
First-Year Sloan Digital Sky Survey-II (SDSS-II) Supernova Results: Constraints on Nonstandard Cosmological Models
Sollerman et al. 2009, ApJ, 703(2), 1374-1385
Second in the SDSS trio. Like for the ESSENCE paper in 2007, here we extended the standard SDSS cosmology fits to test non-standard models, such as new theories of gravity.
First-Year Sloan Digital Sky Survey-II Supernova Results: Hubble Diagram and Cosmological Parameters
Kessler et al. 2009, ApJS, 185(1), 32-84
The main results paper from the first year of SDSS data. This is a mammoth effort from a large group of people. At 53 pages (it was 145 pages in preprint format) you want to put some time aside to read this one. We concentrated on understanding the possible systematics in our signal very well and identified where the most work needs to be done before our final data release next year.
The WiggleZ Dark Energy Survey: small-scale clustering of Lyman-break galaxies at z < 1
Blake et al. 2009, MNRAS, 395(1), 240-254
With our first round of data we are already able to look at the small-scale clustering in the universe. We also make a forecast of how accurate our final baryon acoustic oscillation result is likely to be (i.e. how accurately we're going to be able to figure out what the universe is made of).
The WiggleZ Dark Energy Survey
Blake et al. 2009, Astronomy & Geophysics, 49(5), 5.19-5.24
This article made the cover of Astronomy & Geophysics. It gives the overview of our WiggleZ project with nice glossy pages!
Scrutinizing Exotic Cosmological Models Using ESSENCE Supernova Data Combined with Other Cosmological Probes
Davis et al. 2007, Astrophysical Journal 666, 716
We use model selection criteria to assess a variety of non-standard cosmological models. We rule out DGP and Standard Chaplygin Gas models and although some exotic models were able to get a marginally better fit than the flat cosmological constant model, the small improvement did not justify the additional parameters required. The flat cosmological constant model remains the best description of the accelerating universe.
We also provide for general use a single, consistent, data set that includes ESSENCE, SNLS, Higher-Z and nearby supernova data. To get the data go to http://dark.dark-cosmology.dk/~tamarad/SN/.
Observational Constraints on the Nature of Dark Energy: First Cosmological Results from the ESSENCE Supernova Survey
Wood-Vasey et al. 2007, Astrophysical Journal 666, 694
This is the major first data release and cosmology results from ESSENCE.
The ESSENCE Supernova Survey: Survey Optimization, Observations, and Supernova Photometry
Miknaitis et al. 2007, Astrophysical Journal 666, 674
This is the paper describing the ESSENCE survey strategy and first four years of results.
A search for propylene oxide and glycine in Sagittarius B2 (LMH) and Orion
Cunningham et al. 2007, Monthly Notices of the Royal Astronomical Society, 376, 1201-1210
Using the Mopra mm-wave telescope we searched for the potentially life-seeding molecules glycine and propylene oxide (a simple chiral molecule) in the interstellar medium of Sgr B2 and Orion KL.
No supernovae associated with two long-duration γ-ray bursts
Fynbo et al. 2006, Nature 444, 1047
Previously it had been thought that long gamma-ray bursts were associated with the collapse of massive stars. However in this paper we report the discovery of two long gamma-ray bursts which showed no signs of a supernova in their afterglow. They were close enough that if a supernova had occured we would have seen it -- so if these were associated with a supernova it must have been fainter than any supernova previously observed. It seems we still have some work to do before we understand the progenitor mechanism(s?) of long bursts.
Spectral diversity of Type Ia supernovae
James, Davis, Schmidt and Kim 2006, Monthly Notices of the Royal Astronomical Society 370, 933-940
We measure the diversity of different regions of the supernova spectra and suggest methods (including principal component analysis) to quantify this diversity.
Supernova 2006aj and the associated X-Ray Flash 060218
Sollerman et al. 2006, Astronomy and Astrophysics 454, 503
We compare the supernova associated with this X-Ray Flash (i.e. a long γ-ray burst with low peak energy) to the supernovae associated with γ-ray burst associated supernovae.
Using Line Profiles to Test the Fraternity of Type Ia Supernovae at High and Low Redshifts
Blondin et al. 2006, the Astronomical Journal 131, 1648-1666
We confirm that the spectroscopic properties of distant supernovae are indistinguishable from those of nearby supernovae (to within the accuracy of current observations).
A CH3CN and HCO+ survey towards southern methanol masers associated with star formation
Purcell et al. 2006, Monthly Notices of the Royal Astronomical Society 367, 553-576
We report observations of these organic molecules in maser-selected massive star-forming regions.
Ideal Bandpasses for Type Ia Supernova Cosmology
Davis, Schmidt and Kim 2006, Publications of the Astronomical Society of the Pacific 118, 205-217.
This is my report summarising simulations I performed to determine the optimum bandpass set for the SNAP space telescope.
Misconceptions about the Big Bang
Davis and Lineweaver 2005, Scientific American 292, 36-45
We explore many of the common misconceptions associated with the expansion of the universe.
Also available in the online version of the magazine here.
Expanding Confusion: Common Misconceptions of Cosmological Horizons and the Superluminal Expansion of the Universe
Davis and Lineweaver, 2004, Publications of the Astronomical Society of Australia 21, 1, 97-109
We clarify many of the common misconceptions associated with the expansion of the universe. Including the confusion over recession velocities exceeding the speed of light. (They can do so because the velocities are not being measured in any inertial frame. Special relativity is safe and nothing ever overtakes a light beam.)
Black hole versus cosmological horizon entropy
Davis, Davies and Lineweaver 2003, Classical and Quantum Gravity 20, 2753-2764
We test the generalized second law of thermodynamics as it pertains to the entropy of the cosmological event horizon. Despite our best efforts we could not violate the second law, even when we simulated black holes crossing the event horizon of the universe.
On the Nonobservability of Recent Biogenesis
Lineweaver and Davis 2003, Astrobiology 3, 2, 241-243
We answer our critics by showing that the results of Lineweaver and Davis 2002 are robust to the selection effect imposed by the time needed for intelligent observers to evolve after biogenesis has occured.
Solutions to the tethered galaxy problem in an expanding universe and the observation of receding blueshifted objects
Davis, Lineweaver and Webb 2003, American Journal of Physics, 71, 4, 358-364
Are objects stretched by the expansion of the universe? We show why the answer is no.
Does the Rapid Appearance of Life on Earth Suggest that Life Is Common in the Universe?
Lineweaver and Davis 2002, Astrobiology, 2, 3, 293-304
We show that the rapid appearance of life on earth does imply, statistically, that life should be common in the universe. This is dependent on the assumption that the early Earth-like conditions are relatively common elsewhere, and on the assumption that none of the conditions that were only present early-on in Earth's history (heavy asteroid bombardment, for example) were required for biogenesis.
How far can the generalized second law be generalized?
Davies and Davis 2002, Foundations of Physics 32, 1877-1889
In this honorary issue of Foundations of Physics dedicated to Jacob Bekenstein we pay tribute to his identification of black hole event horizon area with entropy by showing that its extension to cosmological event horizons is also sound.
Cosmology: Black holes constrain varying constants
Davies, Davis and Lineweaver 2002, Nature 418, 6898, 602-603
Black hole entropy is dependent on the constants of nature, the gravitational constant, the speed of light and Planck's constant for example. We show that should the constants of nature change (or rather, dimensionless combinations thereof) it would impact the event horizon size and thus the entropy of the black hole and suggest that ensuring the continued validitiy of the second law of thermodynamics may constrain possible variations in the fundamental constants.
PhD Thesis
Fundamental aspects of the expansion of the universe and cosmic horizons
Davis 2005, Ph.D. dissertation, University of New South Wales 2005.
This won me the UNSW U. Committee Award for Research Excellence, which is awarded each year to the researcher deemed to have submitted the best thesis from across the whole of the Science faculty at UNSW.
Refereed Conference Proceedings
Type Ia supernova diversity: Standardizing the candles
Davis, James, Schmidt and Kim 2007, The Multicolored landscape of compact objects and their explosive origins. AIP Conference proceedings 924, 330-335.
We use principal component analysis to quantify the diversity in type Ia supernova spectra.
What can Rapid Terrestrial Biogenesis Tell Us about Life in the Universe?
Lineweaver and Davis 2004, Bioastronomy 2002: Life Among the Stars, Proceedings of IAU Symposium #213. Edited by R. Norris, and F. Stootman. San Francisco: Astronomical Society of the Pacific, 2003., p.259