Results 91 to 100 of about 50,208 (269)

Deep Extragalactic X-ray Surveys [PDF]

, 2005
Deep surveys of the cosmic X-ray background are reviewed in the context of observational progress enabled by the Chandra X-ray Observatory and the X-ray Multi-Mirror Mission-Newton.
Brandt WN, Brandt WN, Comastri A, Comastri A, Ferrarese L, G. Hasinger, Hasinger G, Hasinger G, Hasinger G, Mainieri V, Miyaji T, Osmer PS, Schmidt M, W.N. Brandt, Zamorani G   +14 more
core   +1 more source

Nakhlite Emplacement as Constrained by X‐Ray Computed Tomography and 3D Quantitative Textural and Petrofabric Analyses

Journal of Geophysical Research: Planets, Volume 130, Issue 12, December 2025.
Abstract Nakhlites, clinopyroxene‐rich rocks, are the largest single‐origin suite of samples from Mars. Despite extensive study to discern their petrogenetic histories, nakhlite emplacement mechanisms and environments are not well‐constrained, and it is unknown whether they represent intrusive or extrusive igneous rocks, or a combination.
Sierra R. Ramsey, Piper Irvin, Arya Udry, Scott A. Eckley, Amanda Ostwald, Richard A. Ketcham   +5 more
wiley   +1 more source

Identifying Compton-thick Active Galactic Nuclei with a Machine Learning Algorithm in Chandra Deep Field-South

The Astrophysical Journal
Compton-thick active galactic nuclei (CT-AGNs), which are defined by column density N _H ≥ 1.5 × 10 ^24 cm ^−2 , emit feeble X-ray radiation, even undetectable by X-ray instruments.
Rui Zhang, Xiaotong Guo, Qiusheng Gu, Guanwen Fang, Jun Xu, Hai-Cheng Feng, Yongyun Chen, Rui Li, Nan Ding, Hongtao Wang   +9 more
doaj   +1 more source

From cells to pixels: A decision tree for designing bioimage analysis pipelines

Journal of Microscopy, Volume 300, Issue 3, Page 384-408, December 2025.
Abstract Bioimaging has transformed our understanding of biological processes, yet extracting meaningful information from complex datasets remains a challenge, particularly for biologists without computational expertise. This paper proposes a simple general approach, to help identify which image analysis methods could be relevant for a given image ...
Elnaz Fazeli, Robert Haase, Michael Doube, Kota Miura, David Legland   +4 more
wiley   +1 more source

[C II] emission from galactic nuclei in the presence of X-rays

, 2015
The luminosity of [C II] is used to probe the star formation rate in galaxies, but the correlation breaks down in some active galactic nuclei (AGNs). Models of the [C II] emission from galactic nuclei do not include the influence of X-rays on the carbon ...
Langer, William D., Pineda, Jorge L.
core   +1 more source

Hidden diversity: Transcriptomic and photosynthetic variation among common ‘wild type’ Chlamydomonas strains

The Plant Journal, Volume 124, Issue 5, December 2025.
SUMMARY The unicellular green alga Chlamydomonas reinhardtii is a widely studied reference organism, particularly in photosynthesis research. It employs photoprotective mechanisms, such as state transitions (ST) and non‐photochemical quenching (NPQ), to cope with rapid light changes. Most widely used strains share a recent common ancestor yet differ by
Xin Liu, Olli Virtanen, Sean D. Gallaher, Wojciech J. Nawrocki, Anne G. Glaesener, Sabeeha S. Merchant, Roberta Croce   +6 more
wiley   +1 more source

X-Ray Polarization Variability of High Spectral Peak BL Lacertaes: Cases of 1ES 1959+650 and PKS 2155–304

The Astrophysical Journal Letters
The high-energy-peaked BL Lacertae objects (HBLs) are the main targets of the Imaging X-ray Polarimetry Explorer (IXPE) for investigating the mechanisms of radiation and particle acceleration in jets. In this Letter, we report the first IXPE observations
Xin-Ke Hu, Yu-Wei Yu, Jin Zhang, Tan-Zheng Wu, Ji-Shun Lian, Xiang-Gao Wang, Hai-Ming Zhang, En-Wei Liang   +7 more
doaj   +1 more source

X-ray variability observed with HEAO A-1 [PDF]

Results from the HEAO A-1 instrument which observed X-ray source variability over a wide range of accessible timescales are surveyed. The objects observed include quasars, BL Lacertae, and active galactic nuclei.
Friedman, H.
core   +1 more source

A systematic cross-search for radio/infrared counterparts of XMM-Newton sources

, 2010
We present a catalog of cross-correlated radio, infrared and X-ray sources using a very restrictive selection criteria with an IDL-based code developed by us.
A. Caccianiga, A. J. Muñoz-Arjonilla, A.D.P. Hands, A.J. Green, B.J. Boyle, C. Feruglio, E. Sánchez-Ayaso, F.J. Carrera, G. E. Romero, G. Fabbiano, G. Micela, G. Novara, I. Furenlid, J. A. Combi, J. Ebrero, J. F. Albacete Colombo, J. López-Santiago, J. López-Santiago, J. Martí, J. R. Sánchez-Sutil, J.J. Condon, J.R. Allington-Smith, L. Pellizza, M. Seldner, M.G. Watson, P. L. Luque-Escamilla, P. Severgnini, P.J.E. Peebles, P.M. Woodward, R. Della Ceca, R. Della Ceca, R.K. Smith, S. Mateos, S. Mateos, X. Barcons, X. Barcons   +35 more
core   +1 more source

A Long-term Study of Mrk 50: Appearance and Disappearance of Soft Excess

The Astrophysical Journal
We present an extensive temporal and spectral study of the Seyfert 1 AGN Mrk 50 using 15 yr (2007–2022) of multiwavelength observations from XMM-Newton, Swift, and NuSTAR for the first time.
Narendranath Layek, Prantik Nandi, Sachindra Naik, Arghajit Jana   +3 more
doaj   +1 more source