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Solar wind models predict that the mass flux carried away from the Sun in the solar wind should be extremely sensitive to the temperature in the corona, where the solar wind is accelerated. We perform a direct test of this prediction in…

Solar and Stellar Astrophysics · Physics 2021-06-02 D. Stansby , L. Berčič , L. Matteini , C. J. Owen , R. French , D. Baker , S. T. Badman

Using Hinode EUV Imaging Spectrometer (EIS) spectra recorded daily at Sun center from the end of 2006 to early 2011, we studied the long-term evolution of the quiet corona. The light curves of the higher temperature emission lines exhibit…

Solar and Stellar Astrophysics · Physics 2012-07-17 S. Kamio , J. T. Mariska

We employ MUSE/VLT data to study the ionised and highly ionised gas phases of the feedback in Circinus, the closest Seyfert 2 galaxy to us. The analysis of the nebular emission allowed us to detect a remarkable high-ionisation gas outflow…

Astrophysics of Galaxies · Physics 2021-06-28 M. A. Fonseca-Faria , A. Rodríguez-Ardila , M. Contini , V. Reynaldi

A NuSTAR/Swift observation of the luminous Seyfert 1 galaxy 1H 0419-577 taken during 2015 reveals one of the most extreme high energy cut-offs observed to date from an AGN - an origin due to thermal Comptonization would imply a remarkably…

High Energy Astrophysical Phenomena · Physics 2018-02-28 T. J. Turner , J. N. Reeves , V. Braito , M. Costa

We analysed the planetary nebula Hen 2-260 using optical spectroscopy and photometry. We compared our observations with the data from literature to search for evolutionary changes. The nebular line fluxes were modelled with the Cloudy…

Solar and Stellar Astrophysics · Physics 2014-07-09 M. Hajduk , P. A. M. van Hoof , K. Gesicki , A. A. Zijlstra , S. K. Górny , M. Gładkowski

A fraction of active galactic nuclei (AGN) exhibit dramatic variability, which is observed on timescales down to minutes in the X-ray band. We introduce the case study of 1H 1934-063 (z = 0.0102), a Narrow-line Seyfert 1 (NLS1) among the…

High Energy Astrophysical Phenomena · Physics 2018-11-07 Sara E. Frederick , Erin Kara , Christopher S. Reynolds , Ciro Pinto , Andrew C. Fabian

We present near-infrared K-band slit spectra of the nuclei of 25 Seyfert 2 galaxies in the CfA and 12 micron samples. The strength of the CO absorption features at 2.3-2.4 micron produced by stars is measured in terms of a spectroscopic CO…

Astrophysics · Physics 2009-11-10 Masatoshi Imanishi , Almudena Alonso-Herrero

The optical and near-ultraviolet (NUV) continuum radiation in M dwarf flares is thought to be the impulsive response of the lower stellar atmosphere to magnetic energy release and electron acceleration at coronal altitudes. This radiation…

Solar and Stellar Astrophysics · Physics 2023-02-07 Adam F. Kowalski

We describe a search for molecular absorption at millimetre wavelengths associated with dusty molecular tori in active galactic nuclei (AGN). The sample observed consists of 11 flat-spectrum radio sources known to have red optical to…

Astrophysics · Physics 2016-08-30 M. Drinkwater , F. Combes , T. Wiklind

The variability of the continuum spectral energy distribution has been analyzed for a complete magnitude-limited sample of quasars in Selected Area 57, observed at two epochs in the photographic $U$, $B_J$, $F$ and $N$ bands with the Mayall…

Astrophysics · Physics 2009-10-31 Dario Trevese , Richard G. Kron , Alessandro Bunone

[Abridged] ESO 141-G55 is a nearby X-ray bright BLS1, which has been classified as a bare AGN due to the lack of warm absorption along its line-of-sight, providing an unhampered view into its disc-corona system. We aim to probe its…

High Energy Astrophysical Phenomena · Physics 2024-09-25 Delphine Porquet , James N. Reeves , Scott Hagen , Andrew Lobban , Valentina Braito , Nicolas Grosso , Frédéric Marin

The Type I active galactic nucleus (AGN) ESO 511-G030, a formerly bright and soft-excess dominated source, has been observed in 2019 in the context of a multi-wavelength monitoring campaign. However, in these novel exposures, the source was…

We report ALMA observations of molecular gas and continuum emission in the 90 and 350 GHz bands toward a nearby Seyfert galaxy NGC 613. Radio continuum emissions were detected at 95 and 350 GHz from both the circum-nuclear disk (CND)…

Astrophysics of Galaxies · Physics 2018-02-05 Yusuke Miyamoto , Naomasa Nakai , Masumichi Seta , Dragan Salak , Makoto Nagai , Hiroyuki Kaneko

We present the first high signal-to-noise broadband X-ray spectrum of the radio-quiet type-2 Seyfert ESO 033-G002, combining data from $XMM$-$Newton$ and $NuSTAR$. The nuclear X-ray spectrum is complex, showing evidence for both neutral and…

We introduce the Keck Osiris Nearby AGN survey (KONA), a new adaptive optics-assisted integral-field spectroscopic survey of Seyfert galaxies. KONA permits at ~0.1" resolution a detailed study of the nuclear kinematic structure of gas and…

Astrophysics of Galaxies · Physics 2018-05-04 F. Müller-Sánchez , E. K. S. Hicks , M. Malkan , R. Davies , P. C. Yu , S. Shaver , B. Davis

The origin of radio emission in radio-quiet (RQ) AGN remains a long-standing mystery. We present a detailed study of the cm to sub-mm emission from the nucleus of the nearby prototypical RQ Seyfert 2 galaxy, NGC 1068. We analyse…

We present a broadband X-ray analysis of a new homogeneous sample of 95 active galactic nuclei (AGN) from the 22-month Swift/BAT all-sky survey. For this sample we treated jointly the X-ray spectra observed by XMM-Newton and INTEGRAL…

High Energy Astrophysical Phenomena · Physics 2015-11-20 A. A. Vasylenko , V. I. Zhdanov , E. V. Fedorova

We study in detail the inner 600 pc of the Seyfert 2 galaxy ESO138-G001 by means of the SOAR Integral Field Spectrograph (SIFS) attached to the SOAR telescope. This source is known for displaying a very rich coronal line spectrum and a blob…

Astrophysics of Galaxies · Physics 2023-12-15 A. Rodríguez-Ardila , D. May , S. Panda , M. A. Fonseca-Faria , L. Fraga

We performed a detailed broadband spectral and timing analysis of a small flaring event of ~120 ks in a narrow-line Seyfert 1 galaxy NGC 4051 using simultaneous XMM-Newton and NuSTAR observations. The ~300 ks long NuSTAR observation and the…

High Energy Astrophysical Phenomena · Physics 2023-03-29 Neeraj Kumari , Arghajit Jana , Sachindra Naik , Prantik Nandi