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Related papers: Slit Observations and Empirical Calculations for H…

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(Abridged) We have obtained new spectrophotometric data for 28 HII regions in the spiral galaxy NGC 300, a member of the nearby Sculptor Group. The detection of auroral lines, including [OIII]4363, [SIII]6312 and [NII]5755, has allowed us…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 Fabio Bresolin , Wolfgang Gieren , Rolf-Peter Kudritzki , Grzegorz Pietrzynski , Miguel A. Urbaneja , Giovanni Carraro

Synthetic stellar spectra are extensively used for many different applications in astronomy, from stellar studies (such as in the determination of atmospheric parameters of observed stellar spectra), to extragalactic studies (e.g. as one of…

Solar and Stellar Astrophysics · Physics 2017-04-05 Jessica R. Kitamura , Lucimara P. Martins , Paula Coelho

We study the effect of inclination on the apparent brightness of star-forming galaxies in spectral passbands that are commonly used as star-formation indicators. As diagnostics we use mass-to-light ratios in three passbands: the UV…

We analyze the stellar and nebular energy distributions of starbursts using our evolutionary synthesis model PEGASE coupled to the photoionization code CLOUDY. The originality of this study is to relate the evolution and the metallicity of…

Astrophysics · Physics 2009-11-06 E. Moy , B. Rocca-Volmerange , M. Fioc

It has long been known that infrared fine structure lines of abundant ions, like the [O III] 88 micron line, can become optically thick in H II regions under certain high luminosity conditions. This could mitigate their potential as…

We have collected from different surveys some significant spectroscopic data observed from star-forming galaxies in the local Universe. The objects showing a relatively rich spectrum in number of lines from different elements were selected…

Astrophysics of Galaxies · Physics 2022-01-19 Marcella Contini

We analysed the optical spectra of HII regions extracted from a sample of 350 galaxies of the CALIFA survey. We calculated total O/H abundances and, for the first time, N/O ratios using the semi-empirical routine HII-CHI-mistry, which,…

In a first of a series of studies of the H-alpha + [NII] emission from nearby spiral galaxies, we present measurements of H-alpha + [NII] emission from HII regions in M81. Our method uses large-field-CCD images and long-slit spectra, and is…

Astrophysics · Physics 2009-11-07 W. P. Lin , X. Zhou , D. Burstein , R. A. Windhorst , J. S. Chen

We have selected the Galactic HII region M43, a close-by apparently spherical nebula ionized by a single star (HD37061) to investigate several topics of recent interest in the field of HII regions and massive stars. In a series of two…

Astrophysics of Galaxies · Physics 2015-05-27 S. Simón-Díaz , J. García-Rojas , C. Esteban , G. Stasińska , A. R. López-Sánchez , C. Morisset

Integral field spectroscopy (IFS) is presented for star forming regions in M33. A central area of 300 x 500 pc^2 and the external HII region IC 132, at a galactocentric distance {\sim} 19arcmin (4.69 kpc) were observed with the Potsdam…

(ABRIDGED) We present an analysis of NGC588 based on IFS data with PMAS, together with Spitzer images at 8 mi and 24 mi. The extinction distribution in the optical shows complex structure, with maxima correlating in position with those of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 A. Monreal-Ibero , M. Relaño , C. Kehrig , E. Pérez-Montero , J. M. Vílchez , A. Kelz , M. M. Roth , O. Streicher

We have developed a robust, automated method, hereafter designated HIIphot, which enables accurate photometric characterization of HII regions while permitting genuine adaptivity to irregular source morphology. HIIphot utilizes…

Astrophysics · Physics 2009-10-31 David A. Thilker , Robert Braun , Rene A. M. Walterbos

We use spectroscopic observations of a sample of 82 HII regions in 76 blue compact galaxies to determine the primordial helium abundance Yp and the slope dY/dZ from the Y-O/H linear regression. To improve the accuracy of the dY/dZ…

Astrophysics · Physics 2008-11-26 Y. I. Izotov , T. X. Thuan

We present a comprehensive survey of CII* absorption detections toward stars within 100 pc in order to measure the distribution of electron densities present in the local interstellar medium (LISM). Using high spectral resolution…

Astrophysics · Physics 2009-11-13 Seth Redfield , Ross E. Falcon

We present Herschel spectroscopy of atomic lines arising in photodissociation regions as well as ionization regions of nearby early-type galaxies (ETGs), focusing on the volume-limited Atlas3D sample. Our data include the [CII], [OI], and…

Astrophysics of Galaxies · Physics 2017-05-10 Ryen Carl Lapham , Lisa M. Young , Alison Crocker

Some aspects of the systematic and statistical errors affecting grid-based estimation of stellar masses and radii have still not been investigated well. We study the impact on mass and radius determination of the uncertainty in the input…

Solar and Stellar Astrophysics · Physics 2015-06-18 G. Valle , M. Dell'Omodarme , P. G. Prada Moroni , S. Degl'Innocenti

We summarize the status of our program of near-infrared adaptive optics observations of ultracompact HII regions. By means of selected results we demonstrate the usefulness of this technique for disentangling the complexity of massive…

Astrophysics · Physics 2007-05-23 Thomas Henning , Markus Feldt , Bringfried Stecklum

We present integral field spectroscopy of two selected zones in the Orion Nebula obtained with the Potsdam Multi-Aperture Spectrophotometer (PMAS), covering the optical spectral range from 3500 to 7200 A and with a spatial resolution of 1".…

Astrophysics of Galaxies · Physics 2015-05-28 A. Mesa-Delgado , M. Núñez-Díaz , C. Esteban , L. López-Martín , J. García-Rojas

With the advent of Integral Field Units (IFUs), surveys can now measure metallicities across the discs of nearby galaxies at scales $\lesssim 100~$ pc. At such small scales, many of these regions contain too few stars to fully sample all…

Astrophysics of Galaxies · Physics 2021-10-07 Raghav Arora , Mark R. Krumholz , Christoph Federrath

We present a study of the consequences of an initial mass function that is stochastically sampled on the main emission lines used for gas-phase metallicity estimates in extra-galactic sources. We use the stochastic stellar population code…

Astrophysics of Galaxies · Physics 2017-07-19 Mieke Paalvast , Jarle Brinchmann
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