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We present an innovative approach to constraining the non-cold dark matter model using a convolutional neural network (CNN). We perform a suite of hydrodynamic simulations with varying dark matter particle masses and generate mock 21cm…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-23 Koya Murakami , Atsushi J. Nishizawa , Kentaro Nagamine , Ikko Shimizu

We report on capacitance-voltage spectroscopy of self-assembled InAs quantum dots under constant illumination. Besides the electronic and excitonic charging peaks in the spectrum reported earlier, we find additional resonances associated…

Mesoscale and Nanoscale Physics · Physics 2018-01-24 Sascha R. Valentin , Jonathan Schwinger , Pia Eickelmann , Patrick A. Labud , Andreas D. Wieck , Björn Sothmann , Arne Ludwig

Standard solar models (SSM) are facing nowadays a new puzzle: the solar composition problem. New determinations of solar metal abundances lead SSM calculations to conflict with helioseismological measurements, showing discrepancies that…

Astrophysics · Physics 2008-11-18 Carlos Pena-Garay , Aldo Serenelli

We attempt to characterise the chemical properties of a sample of massive clumps of IRDCs through multi-molecular line observations. We also search for possible evolutionary trends among the derived chemical parameters. The clumps are…

Astrophysics of Galaxies · Physics 2015-06-17 Oskari Miettinen

This chapter presents a review on the latest advances in the computation of physical conditions and chemical abundances of elements present in photoionized gas H II regions and planetary nebulae). The arrival of highly sensitive…

Solar and Stellar Astrophysics · Physics 2020-07-22 Jorge García-Rojas

The metal line profiles of different ions observed in high HI column density systems [N(HI) > 10^{16} cm^{-2}] in quasar spectra can be used to constrain the ionization structure and kinematic characteristics of the absorbers. For these…

Astrophysics · Physics 2009-11-07 S. A. Levshakov , I. I. Agafonova , M. Centurion , I. E. Mazets

Massive young stellar objects in the Magellanic Clouds show infrared absorption features corresponding to significant abundances of CO, CO$_2$ and H$_2$O ice along the line of sight, with the relative abundances of these ices differing…

Astrophysics of Galaxies · Physics 2018-02-21 Tyler Pauly , R. T. Garrod

Ionized nebulae are key to understanding the chemical composition and evolution of the Universe. Among these nebulae, H~{\sc ii} regions and planetary nebulae are particularly important as they provide insights into the present and past…

Astrophysics of Galaxies · Physics 2023-11-20 José Eduardo Méndez-Delgado , Jorge García-Rojas

We discuss variants of Cold Dark Matter (CDM) dominated cosmological models that give good agreement with a range of observations. We consider models with hot dark matter, tilt, $\Omega < 1$, or a cosmological constant. We also discuss the…

Astrophysics · Physics 2007-05-23 Rachel S. Somerville , Joel R. Primack

We present a study of NV absorption systems at 1.5 < z < 2.5 in the optical spectra of 19 QSOs. Our analysis includes both absorbers arising from the intergalactic medium as well as systems in the vicinity of the background quasar. We…

Astrophysics · Physics 2009-11-13 C. Fechner , P. Richter

As the share of renewables in the grid increases, the operation of power systems becomes more challenging. The present paper proposes a method to formulate and solve chance-constrained optimal power flow while explicitly considering the…

Systems and Control · Computer Science 2019-04-04 T. Mühlpfordt , L. Roald , V. Hagenmeyer , T. Faulwasser , S. Misra

Aims. We study the behaviour of Cl abundance and its ratios with respect to O, S and Ar abundances in a sample of more than 200 spectra of Galactic and extragalactic H ii regions and star-forming galaxies (SFGs) of the local Universe.…

Outflows in the form of fast winds from the accretion disk appear in nearly all high accretion rate cataclysmic variables (CVs), both novalikes (NLs) and dwarf novae in outburst (DN). The primary signatures of CV winds are broad,…

Astrophysics · Physics 2007-05-23 C. S. Froning

We present far-UV spectra of the three magnetic cataclysmic variables (MCVs) BY Cam, V1309 Ori and AE Aqr obtained with the FUSE satellite. These MCVs have revealed strongly unusual NV and CIV UV resonance lines. The FUSE spectra exhibit…

We present a series of hydrodynamic simulations of isolated galaxies with stellar mass of $10^{9} \, \rm{M}_{\odot}$. The models use a resolution of $750 \, \rm{M}_{\odot}$ per particle and include a treatment for the full non-equilibrium…

Astrophysics of Galaxies · Physics 2016-02-17 Alexander J. Richings , Joop Schaye

Estimating molecular abundances ratios from the direct measurement of the emission of the molecules towards a variety of interstellar environments is indeed very useful to advance in our understanding of the chemical evolution of the…

Astrophysics of Galaxies · Physics 2018-09-12 S. Paron , M. B. Areal , M. E. Ortega

So far large and different data sets revealed the accelerated expansion rate of the Universe, which is usually explained in terms of dark energy. The nature of dark energy is not yet known, and several models have been introduced: a non…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-16 M. Demianski , E. Piedipalumbo , D. Sawant , L. Amati

We report high-sensitivity millimetre observations of several molecular species (13CO, HCN, HNC, CN, HCO+ and N2H+) in a sample of compact planetary nebulae. Some species such as HCO+ and CN are particularly abundant compared to envelopes…

Astrophysics · Physics 2009-11-07 E. Josselin , R. Bachiller

Carbon abundances in late-type stars are important in a variety of astrophysical contexts. However C i lines, one of the main abundance diagnostics, are sensitive to departures from local thermodynamic equilibrium (LTE). We present a model…

Solar and Stellar Astrophysics · Physics 2019-04-24 A. M. Amarsi , P. S. Barklem , R. Collet , N. Grevesse , M. Asplund

For the first time, we establish a gas phase abundance pattern calibration for quiescent galaxies using optical emission lines. Quiescent galaxies have warm ionized gas showing line ratios similar to low-ionization nuclear emission line…

Astrophysics of Galaxies · Physics 2018-09-05 Renbin Yan