Results 21 to 30 of about 11,425 (209)

Unravelling the pore network and its behaviour: An integrated NMR, MICP, XCT and petrographical study of continental spring carbonates from the Ballık area, SW Turkey

The Depositional Record, Volume 8, Issue 1, Page 292-316, February 2022., 2022
Applying an integrated methodology, including petrography, mercury injection capillary pressure (MICP), laboratory nuclear magnetic resonance (NMR) and X‐ray computed tomography (XCT), on continental spring carbonate reservoir analogue samples is a prerequisite to understanding plug scale porosity and permeability heterogeneities.
Jeroen Soete, Steven Claes, Hannes Claes, Marcelle M. Erthal, Helen Hamaekers, Eva De Boever, Anneleen Foubert, Norbert Klitzsch, Rudy Swennen   +8 more
wiley   +1 more source

Controversial Issues of Hydrocarbon Field Formation and the Role of Geomagnetic Fields

International Journal of Geophysics, Volume 2022, Issue 1, 2022., 2022
This review paper presents controversial issues on the formation of hydrocarbon deposits. We look into the geological contradictions of the abiogenic and biogenic theories of petroleum origin, indicating the connection between hydrocarbon deposits and disjunctive dislocations, as well as present disputes about the geological period over which ...
Andrey A. Ponomarev, Marsel A. Kadyrov, Yuri V. Vaganov, Valeria A. Cheymetova, Vadim M. Aleksandrov, Aleksandr V. Morev, Arkoprovo Biswas   +6 more
wiley   +1 more source

Four open questions in massive star evolution [PDF]

, 2013
We discuss four questions dealing with massive star evolution. The first one is about the origin of slowly rotating, non-evolved, nitrogen rich stars.
Eggenberger, Patrick, Ekstrom, Sylvia, Georgy, Cyril, Groh, Jose, Maeder, Andre, Meynet, Georges, Moriya, Takashi, Saio, Hideyuki   +7 more
core   +1 more source

Tomography of the red supergiant star μ Cep

Proceedings of the International Astronomical Union, 2018
AbstractA tomographic method, aiming at probing velocity fields at depth in stellar atmospheres, is applied to the red supergiant star μ Cep and to snapshots of 3D radiative-hydrodynamics simulation in order to constrain atmospheric motions and relate them to photometric variability.
K. Kravchenko, A. Chiavassa, S. Van Eck, A. Jorissen, T. Merle, B. Freytag   +5 more
openaire   +4 more sources

Near-IR TRGB Distance to Nearby Dwarf Irregular Galaxy NGC 6822 [PDF]

Journal of Astronomy and Space Sciences, 2008
We report the distance modulus of nearby dwarf irregular galaxy NGC 6822 estimated from the so-called Tip of Red-giant Branch (TRGB) method. To detect the apparent magnitudes of the TRGB we use the color-magnitude diagrams (CMDs) and luminosity functions
Y.-J. Sohn, A. Kang, W, Han, J.-H. Park, H.-I. Kim, J.-W. Kim, I.-G. Shin, S.-H. Chun   +7 more
doaj   +1 more source

Spitzer SAGE-SMC Infrared Photometry of Massive Stars in the Small Magellanic Cloud [PDF]

, 2010
We present a catalog of 5324 massive stars in the Small Magellanic Cloud (SMC), with accurate spectral types compiled from the literature, and a photometric catalog for a subset of 3654 of these stars, with the goal of exploring their infrared properties.
A. Z. Bonanos, Antoniou, Azzopardi, Azzopardi, Azzopardi, B. A. Whitney, B. L. Babler, B. Shiao, Bolatto, Bonanos, C. J. Evans, C. W. Engelbracht, D. J. Lennon, D. L. Massa, de Jager, Dougherty, Evans, F. Köhlinger, Feast, Foellmi, Grebel, Groenewegen, Habing, Ita, J. L. Hora, J. Th. van Loon, K. A. Misselt, K. D. Gordon, Kato, Kippenhahn, Lanz, Lanz, Larsen, Lennon, Levesque, Levesque, M. Block, M. Meixner, M. R. Meade, M. Sewilo, Maeder, Massey, Massey, Massey, Massey, Massey, Massey, Meixner, N. Panagia, Oestreicher, Panagia, Panagia, Pojmański, Prieto, R. Indebetouw, S. Bracker, Skrutskie, Sloan, Srinivasan, Szczygiel, Szymański, T. P. Robitaille, Udalski, Udalski, van Loon, van Loon, van Loon, van Loon, van Loon, van Loon, Wisniewski, Wisniewski, Wright, Zaritsky, Zickgraf   +74 more
core   +3 more sources

Yellow Supergiants and Post-red Supergiant Evolution in the Large Magellanic Cloud

The Astronomical Journal, 2023
The empirical evidence for an upper-mass limit for the red supergiant (RSG) progenitors of the Type II-P SNe at about 18 MSun, raises questions about the fate of the most luminous, most massive RSGs.
Roberta M. Humphreys, Terry J. Jones, John C. Martin   +2 more
doaj   +1 more source

Spectroscopic Constraints on the Stellar Population of Elliptical Galaxies in the Coma Cluster [PDF]

, 2000
Near-IR spectra for a sample of 31 elliptical galaxies in the Coma cluster are obtained. The galaxies are selected to be ellipticals (no lenticulars), with a large spatial distribution, covering both the core and outskirt of the cluster (ie ...
Aaronson, Abraham, B. Mobasher, Bothun, Bower, Caldwell, Doyon, Dressler, Frogel, Goldader, Guzmán, James, Kleinmann, Kuntschner, Mobasher, Mobasher, P. A. James, Pahre, Puxley, Ridgway, Rose, Schweizer, Worthey   +22 more
core   +2 more sources

Atmospheres, magnetism, mass loss of red supergiant stars [PDF]

Proceedings of the International Astronomical Union, 2014
AbstractRed supergiant stars (RSGs) are not only a key evolutionary stage of massive stars participating in the chemical evolution of galaxies, they also represent a fantastic and challenging laboratory of (magneto-)hydrodynamics. We present recent results and on-going research on mass loss, atmospheres, and polarimetric studies of RSGs that reveal a ...
Josselin, E., Lambert, J., Auriere, M., Petit, P., Ryde, N.   +4 more
openaire   +1 more source

Lithium Detection in Red Supergiant Stars of the Perseus Complex

The Astrophysical Journal, 2022
Abstract We present the first systematic study of lithium abundance in a chemically homogeneous sample of 27 red supergiants (RSGs) in the young Perseus complex. For these stars, accurate stellar parameters and detailed chemical abundances of iron and iron peak, CNO, alpha, light, and neutron capture elements have already been obtained ...
C. Fanelli, L. Origlia, A. Mucciarelli, N. Sanna, E. Oliva, E. Dalessandro   +5 more
openaire   +3 more sources