Results 71 to 80 of about 498,367 (290)

The early evolution of Globular Clusters: the case of NGC 2808

, 2004
Enhancement and spread of helium among globular cluster stars have been recently suggested as a way to explain the horizontal branch blue tails, in those clusters which show a primordial spread in the abundances of CNO and other elements involved in ...
Bedin L. R., Bessell M. S., Busso G., Catelan M., D’Antona F., D’Antona F., Francesca D’Antona, Hansen B. M. S., Loup C., Mallia E. A., Piotto G., Sneden C., Sweigart A. V., Ventura P., Ventura P., Vittoria Caloi   +15 more
core   +1 more source

Globular Clusters and Horizontal Branch

, 2004
An analysis of available Galactic globular cluster data on metallicity, ages, the distribution of stars on the horizontal branch and the distribution of the periods of RR0 Lyr variables showed that: 1. The latter two characteristics can be used for determining the Oosterhoff type. 2.
openaire   +2 more sources

Microscopic Insights into Magnetic Warping and Time‐Reversal Symmetry Breaking in Topological Surface States of Rare‐Earth‐Doped Bi2Te3

Advanced Materials, EarlyView.
Magnetic doping of the topological insulator Bi2Te3 with erbium adatoms induces out‐of‐plane magnetism and breaks time‐reversal symmetry, opening a Dirac gap and driving a Fermi surface transition from hexagonal to star‐of‐David geometry. Microscopy, spectroscopy, and magnetic dichroism reveal atomically controlled magnetic interactions that tailor the
Beatriz Muñiz Cano, Fabián Calleja, Ji Dai, Massimo Tallarida, Vera Marinova, Alessandro Barla, Marc G. Cuxart, Pierluigi Gargiani, Gonzalo N. Molina, José Angel Silva‐Guillén, Adriana I. Figueroa, Kevin García‐Díez, Sergio O. Valenzuela, Aitor Mugarza, Amadeo L. Vázquez de Parga, Rodolfo Miranda, Francisco Guinea, Manuela Garnica, Miguel A. Valbuena   +18 more
wiley   +1 more source

Luminous [O III] and [N II] from Tidally Disrupted Horizontal Branch Stars

, 2012
We model the emission lines generated in the photoionised debris of a tidally disrupted horizontal branch star. We find that at late times, the brightest optical emission lines are [N II] \lambda\lambda 6548,6583 and [O III] \lambda\lambda 4959,5007 ...
Barnard, Baumgardt, Behr, Belczynski, Bogdanović, Brassington, Brodie, Charbonnel, Charpinet, Clausen, Colbert, Croton, Dalessandro, Davies, Dorman, Dotter, Drew Clausen, Ferland, Frank, Gratton, Gratton, Heggie, Hills, Irwin, Ivanova, Jimmy A. Irwin, Kundu, Lacy, Lee, Maccarone, Maccarone, Maccarone, Maccarone, Maccarone, Michael Eracleous, Paxton, Peacock, Porter, Ramirez-Ruiz, Rees, Rey, Ripamonti, Roos, Sandage, Sarazin, Searle, Shih, Sigurdsson, Sigurdsson, Sigurdsson, Steinn Sigurdsson, Strubbe, Strubbe, Tautvaišienė, van den Bergh, van Grootel, Zepf   +56 more
core   +1 more source

Transistor‐Level Activation Functions via Two‐Gate Designs: From Analog Sigmoid and Gaussian Control to Real‐Time Hardware Demonstrations

Advanced Materials, EarlyView.
Screen gate‐based transistors are presented, enabling tunable analog sigmoid and Gaussian activations. The SA‐transistor improves MRI classification accuracy, while the GA‐transistor supports precise Gaussian kernel tuning for forecasting. Both functions are implemented in a single device, offering compact, energy‐efficient analog AI processing ...
Junhyung Cho, Youngmin Han, Won Woo Lee, Youngwoo Yoo, Kannan Udaya Mohanan, Chang‐Hyun Kim, Junhwan Choi, Young‐Joon Kim, Wonjun Shin, Hocheon Yoo   +9 more
wiley   +1 more source

The Spectral Evolution along the Z track of the Bright Neutron Star X-ray Binary GX 17+2

, 2011
Z sources are bright neutron-star X-ray binaries, accreting at around the Eddington limit. We analyze the 68 RXTE observations (270 ks) of Sco-like Z source GX 17+2 made between 1999 October 3-12, covering a complete Z track.
Barret, Didier, Homan, Jeroen, Lin, Dacheng, Remillard, Ronald A.   +3 more
core   +1 more source

The PGPUC horizontal branch evolutionary tracks

Astronomy & Astrophysics
Context. The horizontal branch (HB) phase of stellar evolution plays a critical role in understanding the life cycle of stars, particularly in the context of low-mass stars. However, generating theoretical evolutionary tracks for HB stars is computationally intensive, especially when attempting to match a wide range of observational data. Aims.
Aldo A. R. Valcarce, Márcio Catelan, Sânzia Alves, Felipe González-Bordon   +3 more
openaire   +2 more sources

Directional Flow of Confined Polaritons in CrSBr

Advanced Materials, EarlyView.
CrSBr, a layered magnetic semiconductor, naturally channels self‐hybridized excitonpolaritons into highly directional flow. Its intrinsic optical anisotropy, high refractive index, and strong lightmatter coupling enable long‐range guided modes along the a‐axis, with propagation lengths set by their excitonphoton admixture.
Pratap Chandra Adak, Sichao Yu, Jaime Abad‐Arredondo, Biswajit Datta, Andy Cruz, Sorah Fischer, Kseniia Mosina, Zdeněk Sofer, Antonio I. Fernández‐Domínguez, Francisco J. Garcia‐Vidal, Vinod M. Menon   +10 more
wiley   +1 more source

Nature of BD + 17° 4708 [PDF]

, 1970
Oke, Greenstein, and Gunn (1966) called the GO star BD + 17° 4708 a field horizontal-branch star. They determined its effective temperature to be 6000° K, and its surface gravity as log g = 3.0. In his study of field horizontal-branch stars, Newell (1969)
Cohen, Judith G., Greenstein, Jesse L.
core  

3D Anodic Alumina Nanoarchitectures: A Decade of Progress from Foundational Science to Functional Metamaterials

Advanced Materials, EarlyView.
Ordered three‐dimensional anodic aluminum oxide (3D‐AAO) nanoarchitectures with longitudinal and transverse pores enable architecture‐driven metamaterials. The review maps fabrication advances, including hybrid pulse anodization, and shows how 3D‐AAO templates tailor properties across magnetism, energy, catalysis, and sensing.
Marisol Martín‐González
wiley   +1 more source