Results 81 to 90 of about 298,499 (308)

Dark Matter: A Primer

Advances in Astronomy, 2011
Dark matter is one of the greatest unsolved mysteries in cosmology at the present time. About 80% of the Universe's gravitating matter is nonluminous, and its nature and distribution are for the most part unknown.
Katherine Garrett, Gintaras Duda
doaj   +1 more source

Determining impact angle from the spatial distribution of shock metamorphism: A case study of the Gosses Bluff (Tnorala) impact structure, Australia

Meteoritics &Planetary Science, EarlyView.
Abstract The majority of planetary impacts occur at oblique angles. Impact structures on Earth are commonly eroded or buried, rendering the identification of the direction and angle of impact—using methods such as asymmetries in ejecta distribution, surface topographic expression, central uplift structure, and geophysical anomalies—challenging. In this
Eloise E. Matthews, Auriol S. P. Rae, Thomas Kenkmann, Nicholas E. Timms, Aaron J. Cavosie, Marian B. Holness   +5 more
wiley   +1 more source

High-energy astrophysics and cosmology [PDF]

Nuclear Physics B - Proceedings Supplements, 2003
12 pages, 16 eps figures, uses espcrc2.sty. Talk presented at the XIIth International Symposium on Very-High-Energy Cosmic-Ray Interactions, CERN, July ...
openaire   +2 more sources

Vertical profiling of shock attenuation at the Rochechouart impact structure, France

Meteoritics &Planetary Science, EarlyView.
Abstract Rochechouart, south‐west France, is a complex impact structure. Here, we present the first report of shock barometry of quartz from what are likely parautochthonous basement units at depth, based on samples from the 2017 C.I.R.I.R drilling campaign. The crystallographic orientations of 725 sets of PDFs in 512 quartz grains in samples from four
P. Struzynska, S. Alwmark, C. Alwmark, M. H. Poelchau, P. Lambert   +4 more
wiley   +1 more source

The cosmic microwave background: observing directly the early universe

, 2012
The Cosmic Microwave Background (CMB) is a relict of the early universe. Its perfect 2.725K blackbody spectrum demonstrates that the universe underwent a hot, ionized early phase; its anisotropy (about 80 \mu K rms) provides strong evidence for the ...
de Bernardis, Paolo, Masi, Silvia
core   +1 more source

A geophysical investigation of the Roter Kamm impact crater, Namibia

Meteoritics &Planetary Science, EarlyView.
Abstract The Roter Kamm impact crater is located in the southern Namib Desert. The crater has a diameter of 2.5 km and belongs to the category of simple, bowl‐shaped impact craters, with an elevated rim of fractured target rock. The crater's interior is completely buried beneath sediments, preventing extensive surface investigations of the bedrock ...
Hannah Nienhaus, Pritam Yogeshwar, Wiebke Mörbe, Bülent Tezkan, Yajun Liu, Bufelo Lushetile, Martin Melles   +6 more
wiley   +1 more source

Probing new physics at cosmic dawn with 21-cm cosmology

Nuclear Physics B
21-cm cosmology provides an exciting opportunity to probe new physics dynamics in the early universe. In particular, a tiny sub-component of dark matter that interacts strongly with the visible sector may cool the gas in the intergalactic medium and ...
Omer Zvi Katz, Nadav Outmezguine, Diego Redigolo, Tomer Volansky   +3 more
doaj   +1 more source

Constraining pre Big-Bang-Nucleosynthesis Expansion using Cosmic Antiprotons

, 2006
A host of dark energy models and non-standard cosmologies predict an enhanced Hubble rate in the early Universe: perfectly viable models, which satisfy Big Bang Nucleosynthesis (BBN), cosmic microwave background and general relativity tests, may ...
Antonio Masiero, Massimo Pietroni, Mia Schelke, Nicolao Fornengo, R. Durrer, Riccardo Catena   +5 more
core   +1 more source

First Cosmology Results using Type Ia Supernovae from the Dark Energy Survey: Constraints on Cosmological Parameters [PDF]

Astrophysical Journal, 2018
We present the first cosmological parameter constraints using measurements of type Ia supernovae (SNe Ia) from the Dark Energy Survey Supernova Program (DES-SN). The analysis uses a subsample of 207 spectroscopically confirmed SNe Ia from the first three
T. Abbott, S. Allam, P. Andersen, P. Andersen, C. Angus, J. Asorey, A. Avelino, S. Ávila, B. Bassett, K. Bechtol, G. Bernstein, E. Bertin, D. Brooks, D. Brout, P. Brown, D. Burke, J. Calcino, A. Rosell, D. Carollo, M. Kind, J. Carretero, R. Casas, F. Castander, R. Cawthon, P. Challis, M. Childress, A. Clocchiatti, C. Cunha, C. D'Andrea, L. Costa, C. Davis, T. Davis, J. Vicente, D. DePoy, S. Desai, H. Diehl, P. Doel, A. Drlica-Wagner, A. Drlica-Wagner, T. Eifler, A. Evrard, E. Fernandez, A. Filippenko, D. Finley, B. Flaugher, R. Foley, P. Fosalba, J. Frieman, J. Frieman, L. Galbany, J. García-Bellido, E. Gaztañaga, T. Giannantonio, T. Giannantonio, K. Glazebrook, D. Goldstein, S. González-Gaitán, D. Gruen, R. Gruendl, J. Gschwend, Ravi R. Gupta, G. Gutiérrez, W. Hartley, W. Hartley, S. Hinton, D. Hollowood, K. Honscheid, J. Hoormann, B. Hoyle, B. Hoyle, D. James, T. Jeltema, M. Johnson, Michael D. Johnson, E. Kasai, S. Kent, S. Kent, R. Kessler, A. Kim, R. Kirshner, R. Kirshner, E. Kovacs, E. Krause, R. Kron, R. Kron, K. Kuehn, S. Kuhlmann, N. Kuropatkin, O. Lahav, James Lasker, G. Lewis, Ting S. Li, Ting S. Li, C. Lidman, M. Lima, Hsing-Wen Lin, E. MacAulay, M. Maia, K. Mandel, M. March, J. Marriner, J. Marshall, P. Martini, F. Menanteau, C. Miller, R. Miquel, V. Miranda, J. Mohr, J. Mohr, E. Morganson, D. Muthukrishna, D. Muthukrishna, A. Moller, E. Neilsen, R. Nichol, B. Nord, P. Nugent, R. Ogando, A. Palmese, Yen-Chen Pan, A. Plazas, M. Pursiainen, A. Romer, A. Roodman, E. Rozo, E. Rykoff, M. Sako, E. Sanchez, V. Scarpine, R. Schindler, M. Schubnell, D. Scolnic, S. Serrano, I. Sevilla-Noarbe, R. Sharp, Mathew Smith, M. Soares-Santos, F. Sobreira, N. E. Sommer, H. Spinka, E. Suchyta, M. Sullivan, E. Swann, G. Tarlé, D. Thomas, R. Thomas, M. Troxel, B. Tucker, S. Uddin, A. Walker, W. Wester, P. Wiseman, R. Wolf, B. Yanny, Bin-Bin Zhang, Yuanyuan Zhang   +155 more
semanticscholar   +1 more source

Static recrystallization of shocked calcite in Ries impact breccias

Meteoritics &Planetary Science, EarlyView.
Abstract Calcite is prone to chemical and microstructural modifications, especially after having been strained at high stresses and strain rates, as during hypervelocity impact events. These modifications include precipitation from pore fluid as well as replacement of strained volumes by recrystallization. In calcite aggregates of a metagranite breccia
Claudia A. Trepmann, Fabian Dellefant, Lina Seybold, Wolfgang W. Schmahl, Elena Sturm, Daniel Weidendorfer, Sandro Jahn, Iuliia V. Sleptsova, Stuart A. Gilder   +8 more
wiley   +1 more source