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Related papers: Relation between source and temperature fluctuatio…

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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…

Reliable nebular emission line diagnostics are essential for accurately inferring the physical properties (e.g. electron temperature, density, pressure, and metallicity) of H II regions from spectra. When interpreting spectra, it is typical…

Astrophysics of Galaxies · Physics 2026-02-06 Larrance Xing , Nicholas Choustikov , Harley Katz , Alex J. Cameron

We propose granularity noise thermometry (GNT), a fluctuation-based optical thermometry scheme that exploits the intrinsic fluctuations of susceptibility arising from atomic discreteness. The power spectral density of transmitted light…

Atomic Physics · Physics 2026-05-19 Chen-Rong Liu , Yixuan Wang , Xiaowei Wang , Chuang Li , Mingti Zhou , Runxia Tao , Hongwei Chen , Ying Dong

Emission lines in ionized nebulae can provide strong and useful constraints on the properties of both ionizing and non-ionizing stellar populations in regions with star formation, provided that stellar evolution and stellar atmosphere…

Astrophysics · Physics 2007-05-23 Angeles I. Diaz , Marcelo Castellanos

We examine a model for the variable free-free and neutral hydrogen absorption inferred towards the cores of some compact radio galaxies in which a spatially fluctuating medium drifts in front of the source. We relate the absorption-induced…

Astrophysics of Galaxies · Physics 2016-07-27 Jean-Pierre Macquart , Steven Tingay

A development of perturbations of number densities of ions and electrons during recombination epoch is analysed. The equations for relative perturbations of ionization fractions were derived from the system of equations for accurate…

Astrophysics · Physics 2009-11-11 B. Novosyadlyj

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

The variations in Ly$\alpha$ forest opacity observed at $z>5.3$ between lines of sight to different background quasars are too strong to be caused by fluctuations in the density field alone. The leading hypothesis for the cause of this…

Hot Jupiters receive intense incident stellar light on their daysides, which drives vigorous atmospheric circulation that attempts to erase their large dayside-to-nightside flux contrasts. Propagating waves and instabilities in hot Jupiter…

Earth and Planetary Astrophysics · Physics 2020-01-01 Thaddeus D. Komacek , Adam P. Showman

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

This paper presents an updated framework for studying the ionizing conditions and elemental abundances of photoionized, metal-enriched quasar absorption systems. The standard assumption of ionization equilibrium invoked in absorption line…

Astrophysics of Galaxies · Physics 2025-07-23 Suyash Kumar , Hsiao-Wen Chen

We study the current discrepancy between the model-predicted and measured concentrations of Fe++ and Fe3+ in ionized nebulae. We calculate a set of photoionization models, updated with the atomic data relevant to the problem, and compare…

Astrophysics · Physics 2009-11-10 Monica Rodriguez , Robert H. Rubin

(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])…

We present results from photoionization models of low-metallicity HII regions. These nebulae form the basis for measuring the primordial helium abundance. Our models show that the helium ionization correction factor (ICF) can be…

Astrophysics · Physics 2009-10-31 D. R. Ballantyne , G. J. Ferland , P. G. Martin

Differential rotation between the neutron star crust and a more rapidly rotating interior superfluid leads to frictional heating that affects the star's long-term thermal evolution and resulting surface emission. Here we present the results…

Astrophysics · Physics 2009-10-22 K. Van Riper , B. Link , R. Epstein

Cold ions trapped in the vicinity of conductive surfaces experience heating of their oscillatory motion. Typically, the rate of this heating is orders of magnitude larger than expected from electric field fluctuations due to thermal motion…

Atomic Physics · Physics 2018-01-17 Ivan A. Boldin , Alexander Kraft , Christof Wunderlich

This paper looks into various aspects brought to light by numerical work on the generalized interacting winds model for planetary nebulae. First, a detailed comparison between radiative and non-radiative models is made, showing that one's…

Astrophysics · Physics 2007-05-23 Garrelt Mellema , Adam Frank

We present new JVLA multi-frequency measurements of a set of stars in transition from the post-AGB to the Planetary Nebula phase monitored in the radio range over several years. Clear variability is found for five sources. Their light…

Solar and Stellar Astrophysics · Physics 2017-05-03 L. Cerrigone , G. Umana , C. Trigilio , P. Leto , C. S. Buemi , A. Ingallinera

We calculate the properties of 135 stellar supernovae using data from the Open Supernova Catalog. We generate temperatures, radii, luminosities, and expansion velocities using a spherically symmetric optically thick fireball model. These…

High Energy Astrophysical Phenomena · Physics 2022-12-15 Jacob Marshall , Scott Severson

In a very recent work, [1] claim that the scenario of temperature inhomogeneities proposed by [2] ($t2$ > 0) is not able to explain the O$^{2+}$/H$^{+}$ abundance discrepancy observed between the calculations based on the optical [OIII]…

Astrophysics of Galaxies · Physics 2023-10-03 J. Eduardo Méndez-Delgado , César Esteban , Jorge García-Rojas , Kathryn Kreckel , Manuel Peimbert