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Related papers: Electron temperature fluctuations in Seyfert galax…

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We present maps for the electron temperature in the inner kpc of three luminous Seyfert galaxies: Mrk 79, Mrk 348, and Mrk 607 obtained from Gemini GMOS-IFU observations at spatial resolutions of 110-280 pc. We study the distributions of…

The existence and origin of large spatial temperature fluctuations in HII regions and planetary nebulae are assumed to explain the differences between the heavy element abundances inferred from collisionally excited and recombination lines,…

Astrophysics · Physics 2009-11-13 V. A. Oliveira , M. V. F. Copetti , A. C. Krabbe

We derive the electron temperature gradient in the Galactic disk using a sample of HII regions that spans Galactocentric distances 0--17 kpc. The electron temperature was calculated using high precision radio recombination line and…

Astrophysics · Physics 2008-11-26 C. Quireza , R. T. Rood , T. M. Bania , D. S. Balser , W. J. Maciel

Almost a century ago, Johnson and Nyquist presented evidence of fluctuating electrical current and the governing fluctuation dissipation theorem (FDT). Whether, likewise, temperature T can fluctuate is a controversial topic and has led to…

Mesoscale and Nanoscale Physics · Physics 2019-04-11 Bayan Karimi , Fredrik Brange , Peter Samuelsson , Jukka P. Pekola

We present new HST/WFPC2 imagery and STIS long-slit spectroscopy of the planetary nebula NGC 7009. The primary goal was to obtain high spatial resolution of the intrinsic line ratio [O III] 4364/5008 and thereby evaluate the electron…

In Chen et al., 2023 (C23; arXiv:2304.09898), we introduced a new method to directly measure temperature fluctuations and applied it to a nearby dwarf galaxy, Mrk 71, finding a temperature fluctuation parameter $t^2 = 0.008\pm 0.043$. This…

A method is presented to derive electron temperatures and densities of planetary nebulae (PNe) simultaneously, using the observed hydrogen recombination spectrum, which includes continuum and line emission. By matching theoretical spectra…

Astrophysics · Physics 2009-11-10 Y. Zhang , X. -W. Liu , R. Wesson , P. J. Storey , Y. Liu , I. J. Danziger

(Abridged) Aims. We present a homogeneous observational study of electron temperature ($T_{\rm e}$) relations between ionic species: $T_{\rm e}$([N II]), $T_{\rm e}$([O II]), $T_{\rm e}$([O III]), $T_{\rm e}$([S II]), $T_{\rm e}$([S III])…

In this work, we test the validity of $T_e$ - $T_e$ relations in resolved (10-200~pc) measurements of four nearby, low-metallicity (7.25 $\leq$ 12+log(O/H) $\leq$ 8.33), low-mass (10$^{6.78}$ $\leq$ M$_*$/M$_\odot$ $\leq$ 10$^{8.7}$),…

There is evidence for temperature fluctuations in Planetary Nebulae and in Galactic HII regions. If such fluctuations occur in the low-metallicity, extragalactic HII regions used to probe the primordial helium abundance, the derived 4He…

Astrophysics · Physics 2015-06-24 Gary Steigman , Sueli M. Viegas , Ruth Gruenwald

We report measurements of the electron temperature at about a dozen locations in the extended emission-line regions of five active (Seyfert and radio) galaxies. Temperatures (T_{[OIII]} and T_{[NII]}) have been determined from both the…

Astrophysics · Physics 2016-08-30 A. S. Wilson , L. Binette , T. Storchi-Bergmann

We study the statistics of the fluctuating electron temperature in a metallic island coupled to reservoirs via resistive contacts and driven out of equilibrium by either a temperature or voltage difference between the reservoirs. The…

Mesoscale and Nanoscale Physics · Physics 2013-04-04 Tero T. Heikkila , Yuli Nazarov

We discuss the role of the electron temperature in abundance determinations in ionized nebulae (planetary nebulae and giant HII regions). We show that, even when observations provide a direct estimate of Te, abundance determinations may…

Astrophysics · Physics 2007-05-23 Grazyna Stasinska

HII region electron temperatures are a critical ingredient in metallicity determinations and recent observations reveal systematic variations in the temperatures measured using different ions. We present electron temperatures ($T_e$)…

Here, we demonstrate an interplay between superconducting fluctuations and electron-electron interaction (EEI) by low temperature magnetotransport measurements for a set of 2D disordered TiN thin films. While cooling down the sample, a…

Superconductivity · Physics 2023-01-31 Sachin Yadav , Vinay Kaushik , M. P. Saravanan , Sangeeta Sahoo

Aims. The main objective of this article is to provide a simple physical framework with permits a quantitative comparison of measurements of the temperature fluctuations in the ionized interstellar medium with possible mechanisms which can…

Astrophysics · Physics 2007-05-23 C. Giammanco , J. E. Beckman

The $\rm Fe_{1+y}Te_{1-x}Se_x$\ single crystals with the various Se/Te ratios were studied by the microwave absorption and direct current resistivity measurements. The comparison of the microwave absorption data and the resistivity versus…

Superconductivity · Physics 2021-03-05 I. I. Gimazov , N. M. Lyadov , D. A. Chareev , A. N. Vasiliev , Yu. I. Talanov

Large-amplitude electrostatic fluctuations are routinely observed by spacecraft upon traversal of collisionless shocks in the heliosphere. Kinetic simulations of shocks have struggled to reproduce the amplitude of such fluctuations,…

Space Physics · Physics 2025-09-29 Vadim Roytershteyn , Lynn B. Wilson , Li-Jen Chen , Michael Gedalin , Nikolai Pogorelov

We systematically determine the electron density and electron temperature of active galaxies and star-forming galaxies using spectroscopy from the SDSS DR7, while mainly focusing on the NLRs. Density and temperature are determined through…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-18 Zhitai Zhang , Yanchun Liang , François Hammer

While the temperature of the X-ray corona ($\rm{kT_e}$) in active galactic nuclei (AGN) are known for many sources, its variation, if any, is limited to a handful of objects. This is in part due to the requirement of good signal-to-noise…

High Energy Astrophysical Phenomena · Physics 2022-11-30 Indrani Pal , C. S. Stalin
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