no code implementations • 5 Mar 2023 • McCullen Sandora, Vladimir Airapetian, Luke Barnes, Geraint F. Lewis, Ileana Pérez-Rodríguez
If the origin of life is rare and sensitive to the local conditions at the site of its emergence, then, using the principle of mediocrity within a multiverse framework, we may expect to find ourselves in a universe that is better than usual at creating these necessary conditions.
1 code implementation • 19 Jul 2021 • Florian List, Nicholas L. Rodd, Geraint F. Lewis
The two leading hypotheses for the Galactic Center Excess (GCE) in the $\textit{Fermi}$ data are an unresolved population of faint millisecond pulsars (MSPs) and dark-matter (DM) annihilation.
no code implementations • 22 Dec 2020 • Tomaž Zwitter, Janez Kos, Sven Buder, Klemen Čotar, Martin Asplund, Joss Bland-Hawthorn, Andrew R. Casey, Gayandhi M. De Silva, Valentina D'Orazi, Kenneth C. Freeman, Michael R. Hayden, Geraint F. Lewis, Jane Lin, Karin Lind, Sarah L. Martell, Katharine J. Schlesinger, Sanjib Sharma, Jeffrey D. Simpson, Dennis Stello, Daniel B. Zucker, Kevin L. Beeson, Richard de Grijs, Thomas Nordlander, Yuan-Sen Ting, Gregor Traven, Fred Watson, Rob Wittenmyer
GALAH+ is a magnitude-limited survey of high resolution stellar spectra obtained by the HERMES spectrograph at the Australian Astronomical Observatory.
Solar and Stellar Astrophysics Astrophysics of Galaxies Instrumentation and Methods for Astrophysics
1 code implementation • 4 Nov 2020 • Sven Buder, Sanjib Sharma, Janez Kos, Anish M. Amarsi, Thomas Nordlander, Karin Lind, Sarah L. Martell, Martin Asplund, Joss Bland-Hawthorn, Andrew R. Casey, Gayandhi M. De Silva, Valentina D'Orazi, Ken C. Freeman, Michael R. Hayden, Geraint F. Lewis, Jane Lin, Katharine. J. Schlesinger, Jeffrey D. Simpson, Dennis Stello, Daniel B. Zucker, Tomaz Zwitter, Kevin L. Beeson, Tobias Buck, Luca Casagrande, Jake T. Clark, Klemen Cotar, Gary S. Da Costa, Richard de Grijs, Diane Feuillet, Jonathan Horner, Shourya Khanna, Prajwal R. Kafle, Fan Liu, Benjamin T. Montet, Govind Nandakumar, David M. Nataf, Melissa K. Ness, Lorenzo Spina, Gregor Traven, Thor Trepper-Garcia, Yuan-Sen Ting, Rok Vogrincic, Robert A. Wittenmyer, Marusa Zerjal, the GALAH collaboration
Based on kinematics, 4% are halo stars.
Astrophysics of Galaxies Solar and Stellar Astrophysics
no code implementations • 27 Aug 2020 • Yu-Ching Chen, Xin Liu, Wei-Ting Liao, A. Miguel Holgado, Hengxiao Guo, Robert A. Gruendl, Eric Morganson, Yue Shen, Kaiwen Zhang, Tim M. C. Abbott, Michel Aguena, Sahar Allam, Santiago Avila, Emmanuel Bertin, Sunayana Bhargava, David Brooks, David L. Burke, Aurelio Carnero Rosell, Daniela Carollo, Matias Carrasco Kind, Jorge Carretero, Matteo Costanzi, Luiz N. da Costa, Tamara M. Davis, Juan De Vicente, Shantanu Desai, H. Thomas Diehl, Peter Doel, Spencer Everett, Brenna Flaugher, Douglas Friedel, Joshua Frieman, Juan García-Bellido, Enrique Gaztanaga, Karl Glazebrook, Daniel Gruen, Gaston Gutierrez, Samuel R. Hinton, Devon L. Hollowood, David J. James, Alex G. Kim, Kyler Kuehn, Nikolay Kuropatkin, Geraint F. Lewis, Christopher Lidman, Marcos Lima, Marcio A. G. Maia, Marisa March, Jennifer L. Marshall, Felipe Menanteau, Ramon Miquel, Antonella Palmese, Francisco Paz-Chinchón, Andrés A. Plazas, Eusebio Sanchez, Michael Schubnell, Santiago Serrano, Ignacio Sevilla-Noarbe, Mathew Smith, Eric Suchyta, Molly E. C. Swanson, Gregory Tarle, Brad E. Tucker, Tamas Norbert Varga, Alistair R. Walker
We present a systematic search for periodic light curves in 625 spectroscopically confirmed quasars with a median redshift of 1. 8 in a 4. 6 deg$^2$ overlapping region of the Dark Energy Survey Supernova (DES-SN) fields and the Sloan Digital Sky Survey Stripe 82 (SDSS-S82).
High Energy Astrophysical Phenomena Astrophysics of Galaxies
1 code implementation • 22 Jun 2020 • Florian List, Nicholas L. Rodd, Geraint F. Lewis, Ishaan Bhat
In simulated data, our neural network (NN) is able to reconstruct the flux of inner Galaxy emission components to on average $\sim$0. 5%, comparable to the non-Poissonian template fit (NPTF).
1 code implementation • 19 Feb 2020 • Florian List, Geraint F. Lewis
Creating a database of 21cm brightness temperature signals from the Epoch of Reionisation (EoR) for an array of reionisation histories is a complex and computationally expensive task, given the range of astrophysical processes involved and the possibly high-dimensional parameter space that is to be probed.
no code implementations • 1 Oct 2019 • Florian List, Ishaan Bhat, Geraint F. Lewis
Traditionally, incorporating additional physics into existing cosmological simulations requires re-running the cosmological simulation code, which can be computationally expensive.
Cosmology and Nongalactic Astrophysics
no code implementations • 18 Oct 2017 • Jaime Salcido, Richard G. Bower, Luke A. Barnes, Geraint F. Lewis, Pascal J. Elahi, Tom Theuns, Matthieu Schaller, Robert A. Crain, Joop Schaye
Interestingly, simulations without feedback from accreting black holes predict an upturn in the cosmic star formation rate for $t>15$ Gyr due to the rejuvenation of massive ($ > 10^{11} \mathrm{M}_{\odot}$) galaxies.
Cosmology and Nongalactic Astrophysics
1 code implementation • 4 Aug 2015 • Brendon J. Brewer, David Huijser, Geraint F. Lewis
We introduce a Bayesian solution to the problem of inferring the density profile of strong gravitational lenses when the lens galaxy may contain multiple dark or faint substructures.
Instrumentation and Methods for Astrophysics Cosmology and Nongalactic Astrophysics Astrophysics of Galaxies Data Analysis, Statistics and Probability Applications