Results 81 to 90 of about 25,311 (211)

Building a Continental‐Scale Geodetic Network: The Plate Boundary Observatory (PBO)

open access: yesPerspectives of Earth and Space Scientists, Volume 7, Issue 1, December 2026.
Abstract The Plate Boundary Observatory (PBO) transformed the use of geodesy in North America to study crustal deformation and plate boundary processes by establishing a continental‐scale, standardized, open‐access geodetic network. Built and operated by UNAVCO between 2003 and 2018 as part of the National Science Foundation (NSF)‐funded EarthScope ...
Emily E. Zawacki   +5 more
wiley   +1 more source

Varstrometry for Dual Active Galactic Nuclei Using Radio Interferometry: VaDAR with the VLBA

open access: yesThe Astrophysical Journal
Multiple active galactic nuclei (multi-AGN) are a known result of galaxy mergers. Therefore, they are an important tool for studying the formation and dynamical evolution of galaxies and supermassive black holes. A novel method for the selection of multi-
Emma Schwartzman   +8 more
doaj   +1 more source

A TWO-PARAMETER MODEL FOR THE INFRARED/SUBMILLIMETER/RADIO SPECTRAL ENERGY DISTRIBUTIONS OF GALAXIES AND ACTIVE GALACTIC NUCLEI [PDF]

open access: yes, 2014
A two-parameter semi-empirical model is presented for the spectral energy distributions of galaxies with contributions to their infrared–submillimeter–radio emission from both star formation and accretion disk-powered activity.
D. Dale   +5 more
semanticscholar   +1 more source

A Low‐Power Radioisotope XRF Spectrometer for Detection of Light Elements on Planetary Missions

open access: yesX-Ray Spectrometry, Volume 55, Issue 5, Page 721-729, September/October 2026.
ABSTRACT Current X‐ray spectrometers for in situ geochemical analysis on planetary missions typically rely either on X‐ray tubes, which demand electrical power and add mass and thermal complexity, or on alpha particle X‐ray spectrometers (APXS) that use rare 244 Cm sources, and come with severe concerns on radiation safety and isotope availability.
Leandro Silveri   +14 more
wiley   +1 more source

Testing the Linear Relationship between Black Hole Mass and Variability Timescale in Low-luminosity AGNs at Submillimeter Wavelengths

open access: yesThe Astrophysical Journal, 2023
The variability of submillimeter emission provides a useful tool to probe the accretion physics in low-luminosity active galactic nuclei. We accumulate four years of observations using the Submillimeter Array for Centaurus A, NGC 4374, NGC 4278, and NGC ...
Bo-Yan Chen   +7 more
doaj   +1 more source

Fast radio bursts in the discs of active galactic nuclei

open access: yesMonthly Notices of the Royal Astronomical Society
ABSTRACT Fast radio bursts (FRBs) are luminous millisecond-duration radio pulses with extragalactic origin, which were discovered more than a decade ago. Despite the numerous samples, the physical origin of FRBs remains poorly understood. FRBs have been thought to originate from young magnetars or accreting compact objects (COs). Massive
Z Y Zhao, K Chen, F Y Wang, Zi-Gao Dai
openaire   +2 more sources

The SVP–FRO6 Module Integrates the Control of Leaf Senescence and Flowering in Arabidopsis

open access: yesPlant, Cell &Environment, Volume 49, Issue 9, Page 7191-7209, September 2026.
ABSTRACT Plants coordinate major developmental transitions by integrating intrinsic genetic programs with environmental signals, where nutrient availability serves as a critical external factor shaping growth and fitness. Iron (Fe), an essential micronutrient for cellular respiration and photosynthesis, is strictly regulated through sophisticated ...
Hyunsu Park   +8 more
wiley   +1 more source

The Merging Galaxy Cluster Environment Affects the Morphology of Radio Active Galactic Nuclei

open access: yesThe Astrophysical Journal
It has previously been found that the galaxy cluster environment can affect the fueling and evolution of active galactic nuclei (AGN). This work examines the effect of the merging cluster environment on the properties of radio AGN by comparing the radio ...
Mary Rickel   +6 more
doaj   +1 more source

Overview and Status of the International Celestial Reference Frame as Realized by VLBI

open access: yesUniverse, 2022
Accurate measurement of angular positions on the sky requires a well-defined system of reference that is realized with accessible objects. The purpose of this study is to review the international standard realization of such a system, the International ...
Aletha de Witt   +3 more
doaj   +1 more source

Discovery of Giant Radio Sources from TGSS Alternative Data Release 1: Radio, Optical, and Infrared Properties

open access: yesThe Astrophysical Journal Supplement Series
Giant radio sources (GRSs) are the single largest astrophysical objects known in the Universe that have grown to megaparsec scales (≥0.7 Mpc). GRSs are much rarer compared with normal-sized radio galaxies.
Netai Bhukta   +3 more
doaj   +1 more source

Home - About - Disclaimer - Privacy