Results 21 to 30 of about 544 (185)
ENVIRONMENT DENSITY OF A GIANT RADIO STRUCTURE FOR GALAXIES AND QUASARS WITH STEEP RADIO SPECTRA [PDF]
Radio Physics and Radio Astronomy, 2021 Purpose: Estimate of the environment density of giant (with the linear size of about megaparsec) radio structures for galaxies and quasars with steep low-frequency spectra taken from the UTR-2 catalogue. Study of the cosmological evolution of environment
A. P. Miroshnichenko
doaj +1 more source
Chemical abundances in the dwarf galaxy NGC 4163 based on the nebular and auroral emission lines
Astronomische Nachrichten, Volume 343, Issue 9-10, November-December 2022., 2022 Abstract We constructed an oxygen abundance map and N/O ratio map of the unusually low excitation dwarf irregular galaxy NGC 4163 based on publicly available spectroscopy obtained by the MaNGA survey. We detected auroral emission line [O II]λλ$$ \lambda \lambda $$7320,7330 which allows us to measure chemical abundance by direct Te$$ {\mathrm{T}}_e ...
I. A. Zinchenko, L. S. Pilyugin
wiley +1 more source
CATALOG OF VARIABILITY PERIODS OF EXTRAGALACTIC RADIO SOURCES AT CENTIMETER WAVELENGTHS
Radio Physics and Radio Astronomy, 2016 Purpose: Study of the variability of flux density of extragalactic radio sources (3C 273, 3C 120, 3C 345, 3C 446, 3C 454.3, OJ 287, OT 081, BL Lac, DA 55, CTA 102) according to a long-term (1965–2011) monitoring at 14.5, 8, 4.8 GHz made with a 26-m ...
M. I. Ryabov +2 more
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A Comprehensive Observational Study of the FRB 121102 Persistent Radio Source
The Astrophysical Journal, 2023 FRB 121102 is the first fast radio burst to be spatially associated with a persistent radio source (QRS 121102), the nature of which remains unknown. We constrain the physical size of QRS 121102 by measuring its flux-density variability with the VLA from
Ge Chen, Vikram Ravi, Gregg W. Hallinan
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Soft X‐Ray Imaging of Magnetopause Reconnection Outflows Under Low Plasma‐β Solar Wind Conditions
Geophysical Research Letters, Volume 49, Issue 19, 16 October 2022., 2022 Abstract We examined soft X‐ray emission by the solar wind charge‐exchange process around the Earth's magnetosphere using a global magnetohydrodynamic simulation model. The dayside magnetopause reconnection heats and accelerates the plasma whereby the X‐ray emission becomes as bright as ∼6 × 10−6 eV cm−3 s−1 under the southward interplanetary magnetic ...
Yosuke Matsumoto, Yoshizumi Miyoshi
wiley +1 more source
A Wideband Polarization Observation of Hydra A with the Jansky Very Large Array
The Astrophysical Journal, 2023 We present the results of a wideband high-resolution polarization study of Hydra A, one of the most luminous FR I radio galaxies known and among the most well studied. The radio emission from this source displays extremely large Faraday rotation measures
Lerato Baidoo +5 more
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Radio Science, Volume 57, Issue 9, September 2022., 2022 Abstract This article focuses on the new generation of geodetic very long baseline interferometry (VLBI), the VLBI global observing system (VGOS), and measurements carried out during the CONT17 campaign. It uses broadband technology that increases both the number and precision of observations.
Sanam Motlaghzadeh +4 more
wiley +1 more source
Radio Physics and Radio Astronomy, 2017 Purpose: From April 2017, a monitoring program of observations has been started at the RT-16 telescope of Ventspils Radio Astronomy Center (frequencies 5, 6.1, 6.7, 8.4 GHz) to study the intraday and interdiurnal variability of extragalactic radio ...
A. L. Sukharev +4 more
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Luminous Radio Emission from the Superluminous Supernova 2017ens at 3.3 yr after Explosion
The Astrophysical Journal Letters, 2023 We present the results from a multiyear radio campaign of the superluminous supernova (SLSN) SN 2017ens, which yielded the earliest radio detection of an SLSN to date at the age of ∼3.3 yr after explosion. SN 2017ens was not detected at radio frequencies
Raffaella Margutti +19 more
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A search for candidate radio supernova remnants in the nearby irregular starburst galaxies NGC 4214 and NGC 4395 [PDF]
Serbian Astronomical Journal, 2005 We present the results of a search for new candidate radio supernova remnants (SNRs) in the nearby starburst irregular galaxies NGC 4214 and NGC 4395 using archived radio observations made with the Very Large Array (VLA) at the wavelengths of 3.5 cm, 6 ...
Vukotić B. +3 more
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