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Related papers: How old are the HII Galaxies?

200 papers

I review recent observational and theoretical progress in our understanding of the cosmic evolution of luminous sources. Largely due to a combination of deep HST imaging, Keck spectroscopy, and COBE far-IR background measurements, new…

Astrophysics · Physics 2009-10-31 Piero Madau

Recent observations with the Hubble Space Telescope (HST) have revealed that a large fraction of late-type (Sc and later) spiral galaxies harbor a bright, compact stellar cluster in their dynamical centers. Statistics of the mass, age, and…

Astrophysics · Physics 2007-05-23 T. Boeker

We present a high spatial resolution CCD surface photometry study in the optical V, R and I broadband filters of a sample of 15 HII galaxies. The colours of the starburst continuum and of the underlying galaxy are measured. The distribution…

Astrophysics · Physics 2015-06-24 Eduardo Telles , Roberto Terlevich

The morphology of HII regions around young star clusters provides insight into the timescales and physical processes that clear a cluster's natal gas. We study ~700 young clusters (<10Myr) in three nearby spiral galaxies (NGC 7793, NGC…

We combine star-formation histories derived from observations of high redshift galaxies with measurements of the z~0 relation between gas-phase metallicity, stellar mass, and star formation rate to make an explicit and completely empirical…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-16 Molly S. Peeples , Rachel S. Somerville

The degree of influence that environment and mass have on the stellar populations of early-type galaxies is uncertain. In this paper we present the results of a spectroscopic analysis of the stellar populations of early-type galaxies aimed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Craig Harrison , Matthew Colless , Harald Kuntschner , Warrick Couch , Roberto De Propris , Michael Pracy

We consider some aspects of the evolution of massive stars which can only be elucidated by means of "indirect" observations, i.e. measurements of the effects of massive stars on their environments. We discuss in detail the early evolution…

Astrophysics · Physics 2016-01-27 Nino Panagia

One of the fundamental goals of modern Astronomy is to estimate the physical parameters of galaxies from images in different spectral bands. We present a hierarchical Bayesian model for obtaining age maps from images in the \Ha\ line (taken…

Astrophysics of Galaxies · Physics 2015-10-09 M. Carmen Sánchez Gil , Angel Berihuete , Emilio J. Alfaro , Enrique Pérez , Luis M. Sarro

We present $[OIII]/H_{\rm \beta}$ emision line flux ratio predictions for galaxies at $z \sim 7-9$ using the MAPPINGS V v5.2.0 photoionization modelling code combined with an analytic galaxy formation model. Properties such as pressure and…

Astrophysics of Galaxies · Physics 2025-04-08 Aadarsh Pathak , J. Stuart B. Wyithe , Ralph S. Sutherland , L. J Kewley

The baryonic processes in galaxy evolution include gas infall onto galaxies to form neutral atomic hydrogen (HI), the conversion of HI to the molecular state (H$_2$), and, finally, the conversion of H$_2$ to stars. Understanding galaxy…

Astrophysics of Galaxies · Physics 2022-08-05 Aditya Chowdhury , Nissim Kanekar , Jayaram Chengalur , Shiv Sethi , K. S. Dwarakanath

The relative alignments of mid-infrared traced Galactic bubbles are compared to the orientation of the mean Galactic magnetic field in the disk. The orientations of bubbles in the northern Galactic plane were measured and are consistent…

Astrophysics of Galaxies · Physics 2015-06-11 Michael D. Pavel , Dan P. Clemens

We present a stellar population study of three HII galaxies (Mrk 36, UM 408, and UM 461) based on the analysis of new ground-based high resolution near-infrared J, H and Kp broad-band and Br narrow-band images obtained with Gemini/NIRI. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Patricio Lagos , Eduardo Telles , A. Nigoche-Netro , Eleazar Rodrigo Carrasco

Context. Determining stellar characteristics such as the radius, the mass or the age is crucial when studying stellar evolution, exoplanetary systems or characterising stellar populations in the Galaxy. Asteroseismology is the golden path…

Solar and Stellar Astrophysics · Physics 2015-01-28 Gaël Buldgen , Daniel Roy Reese , Marc-Antoine Dupret , Réza Samadi

A significant fraction of stars in globular clusters (about 70%-85%) exhibit peculiar chemical patterns with strong abundance variations in light elements along with constant abundances in heavy elements. These abundance anomalies can be…

Astrophysics · Physics 2015-05-13 T. Decressin , H. Baumgardt , P. Kroupa , G. Meynet , C. Charbonnel

This review covers age-dating methods applied to young stellar populations in starburst galaxies with ages of 10^8 yr and less. First, recent advances in stellar modeling, both for the interior and the atmospheres, are discussed and…

Astrophysics · Physics 2009-11-10 Claus Leitherer

We present near-infrared (H- and K-band) SINFONI integral-field observations of the circumnuclear star formation rings in five nearby spiral galaxies. We made use of the relative intensities of different emission lines (i.e. [FeII], HeI,…

Astrophysics · Physics 2009-11-13 J. Falcón-Barroso , T. Boeker , E. Schinnerer , J. H. Knapen , S. Ryder

We present illustrative models for the UV to millimeter emission of starburst galaxies which are treated as an ensemble of optically thick giant molecular clouds (GMCs) centrally illuminated by recently formed stars. The models follow the…

Astrophysics · Physics 2009-10-31 A. Efstathiou , M. Rowan-Robinson , R. Siebenmorgen

This work investigates the use of a well-known empirical correlation between the velocity dispersion, metallicity, and luminosity in H beta of nearby HII galaxies to measure the distances to HII-like starburst galaxies at high redshifts.…

HII galaxies are clumpy and their gas kinematics can be mapped to show the global turbulent motions and the effect of massive star evolution. The distribution of their physical conditions is homogeneous and oxygen abundance is uniform. The…

Astrophysics of Galaxies · Physics 2014-02-14 Eduardo Telles

We present a catalog of $\sim$52,000 extragalactic HII regions and their spectroscopic properties obtained using Integral Field Spectroscopy (IFS) from MUSE observations. The sample analyzed in this study contains 678 galaxies within the…