Results 31 to 40 of about 472 (148)

Open Questions in Cosmic-Ray Research at Ultrahigh Energies

Frontiers in Astronomy and Space Sciences, 2019
We review open questions and prospects for progress in ultrahigh-energy cosmic ray (UHECR) research, based on a series of discussions that took place during the “The High-Energy Universe: Gamma-Ray, Neutrino, and Cosmic-ray Astronomy” MIAPP workshop in ...
Rafael Alves Batista, Jonathan Biteau, Mauricio Bustamante, Klaus Dolag, Klaus Dolag, Ralph Engel, Ke Fang, Karl-Heinz Kampert, Dmitriy Kostunin, Miguel Mostafa, Kohta Murase, Kohta Murase, Foteini Oikonomou, Angela V. Olinto, Mikhail I. Panasyuk, Guenter Sigl, Andrew M. Taylor, Michael Unger   +17 more
doaj   +1 more source

Reduced Geomagnetic Shielding During the Laschamps Excursion and Its Impact on Cosmic‐Ray‐Induced Atmospheric Radiation

Journal of Geophysical Research: Space Physics, Volume 131, Issue 2, February 2026.
Abstract The Laschamps geomagnetic excursion (≈41,000 years BP) was a period of significant weakening and incomplete reversal of the Earth's magnetic field. The weakening substantially reduced geomagnetic shielding against cosmic rays (CRs), which contribute to phenomena at Earth, such as cosmogenic isotope production, and atmospheric ionisation and ...
N. Larsen, I. Usoskin, A. Mishev, S. Koldobskiy, P. Väisänen   +4 more
wiley   +1 more source

The Chinese Radio Telescope Array for Interplanetary Scintillation Monitoring

Space Weather, Volume 24, Issue 1, January 2026.
Abstract Solar flares, coronal mass ejections (CMEs) and enegertic particles, etc., are the driving sources that may cause catastrophic space weathers. It is desirable to obtain information of solar eruptions like flares and CMEs, etc., propagating from the Sun to the near‐Earth space.
Yihua Yan, Wei Wang, Jin Fan, Ming Xiong, Zhijun Chen, Linjie Chen, Cang Su, Sha Li, Jun Cheng, Jing Du, Xueshang Feng   +10 more
wiley   +1 more source

New Observational Recipes for Measuring Dynamical States of Galaxy Clusters

The Astrophysical Journal
During cluster assembly, a cluster’s virialization process leaves behind signatures that can provide information on its dynamical state. However, no clear consensus yet exists on the best way to achieve this.
Hyowon Kim, Rory Smith, Jongwan Ko, Jong-Ho Shinn, Kyungwon Chun, Jihye Shin, Jaewon Yoo   +6 more
doaj   +1 more source

The Stochastic‐Dissipative Störmer Problem‐Trajectories and Radiation Patterns

Annalen der Physik, Volume 537, Issue 12, December 2025.
We consider charged particle motion and radiation in a dipole magnetic field, in the presence of friction and of stochastic forces. The numerical solutions of the Langevin equation reveal how these forces modify the complex dynamics of particles, and they offer some new insights into the nonlinear processes relevant to planetary radiation belts ...
Tiberiu Harko, Gabriela Raluca Mocanu
wiley   +1 more source

Comparing Inside-out and Outside-in Quenching Modes in MaNGA Observation and MaNGIA Simulation

The Astrophysical Journal
This study probes the inside-out and outside-in quenching status of galaxies to understand the internal and external quenching sources responsible and their roles in galaxy evolution.
Hung-Yu Jian, Lihwai Lin, Connor Bottrell, Bau-Ching Hsieh, Carlos López-Cobá, Zi-Hua Ho, Shuai Feng, Shiyin Shen   +7 more
doaj   +1 more source

Radial and Local Density Dependence of Star Formation Properties in Galaxy Clusters from the Hyper Suprime-Cam Survey

The Astrophysical Journal, 2023
This study examines the impact of cluster environments on galaxy properties using data from the Hyper Suprime-Cam Subaru Strategic Program and an optically selected CAMIRA cluster sample.
Hung-Yu Jian, Lihwai Lin, Bau-Ching Hsieh, Keiichi Umetsu, Carlos Lopez-Coba, Masamune Oguri, Connor Bottrell, Yoshiki Toba, Yusei Koyama, Yu-Yen Chang, Tadayuki Kodama, Yutaka Komiyama, Surhud More, Kai-Yang Lin, Atsushi J. Nishizawa, Ichi Tanaka   +15 more
doaj   +1 more source

A Comparative Study of VTEC Estimates Derived From S/X VLBI and VGOS Observations

Space Weather, Volume 23, Issue 12, December 2025.
Abstract The ionosphere, which strongly varies in time and space, is one of the largest error sources for microwave measurements, if not accounted for accurately. Especially for single‐frequency observations, precise ionospheric models are needed to correct for the ionospheric delays. This study explores the utility of Very Long Baseline Interferometry
Arno Rüegg, Grzegorz Kłopotek, Benedikt Soja   +2 more
wiley   +1 more source

Thermal Structure and Chemical Enrichment of the North and South Polar Spurs: Supersolar N/O and Ne/O in the X-Ray Plasma

The Astrophysical Journal
The North Polar Spur (NPS) is a prominent diffuse X-ray feature whose origin has remained uncertain for decades. Using a uniform analysis of archival Suzaku and XMM-Newton data with new Chandra observations, we constrain its thermal and chemical ...
Anjali Gupta, Smita Mathur, Joshua Kingsbury, Anthony Taylor, Sanskriti Das, Joy Bhattacharya, Manami Roy, Yair Krongold   +7 more
doaj   +1 more source

HEAD IN THE STARS, FEET ON THE GROUND: Scale and Astronomy Initiatives in Southern Africa

Cultural Anthropology, Volume 40, Issue 4, Page 571-596, November 2025.
ABSTRACT This article explores the evolution of radio astronomy in South Africa and Madagascar, focusing on how “scale” functions as both a way of understanding the world and marking differences in existence. In outer space research, the ground is crucial but often overlooked.
HANNA NIEBER, DAVIDE CHINIGÒ
wiley   +1 more source