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Related papers: High-Redshift Galaxies with Large Ionization Param…

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We are in the golden age for the search for high-redshift galaxies, made possible by a combination of new instruments and innovative search techniques. One of the major aims of such searches is to constrain the epoch of reionization (EoR),…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Pratika Dayal

(abridged) We present 8.2m VLT spectroscopic observations of 28 HII regions in 16 emission-line galaxies and 3.6m ESO telescope spectroscopic observations of 38 HII regions in 28 emission-line galaxies. These emission-line galaxies were…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-30 N. G. Guseva , P. Papaderos , H. T. Meyer , Y. I. Izotov , K. J. Fricke

We explore the properties of high-redshift Lyman-alpha emitters (LAE), and their link with the Lyman-Break galaxy population (LBG), using a semi-analytic model of galaxy formation that takes into account resonant scattering of Lya photons…

Astrophysics of Galaxies · Physics 2015-06-24 T. Garel , J. Blaizot , B. Guiderdoni , L. Michel-Dansac , M. Hayes , A. Verhamme

The variations of the metallicity and ionization parameter in HII regions are usually thought to be the dominant factors that produce the variations we see in the observed emission line spectra. There is an increasing amount of evidence…

Astrophysics of Galaxies · Physics 2022-03-16 Xihan Ji , Renbin Yan

The redshift-dependent fraction of color-selected galaxies revealing Lyman alpha emission has become the most valuable constraint on the evolving neutrality of the early intergalactic medium. However, in addition to resonant scattering by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Matthew A. Schenker , Richard S. Ellis , Nick P. Konidaris , Daniel P. Stark

This Letter presents a new, remarkably simple diagnostic specifically designed to derive chemical abundances for high redshift galaxies. It uses only the H \alpha, [N II] and [S II] emission lines, which can usually be observed in a single…

Astrophysics of Galaxies · Physics 2016-02-03 Michael A. Dopita , Lisa J. Kewley , Ralph S. Sutherland , David C. Nicholls

Emission line diagnostic diagrams probing the ionization sources in galaxies, such as the Baldwin-Phillips-Terlevich (BPT) diagram, have been used extensively to distinguish AGN from purely star-forming galaxies. Yet, they remain poorly…

Data on galaxies at high redshift, identified by the Lyman-break photometric technique, can teach us about how galaxies form and evolve. The stellar masses and other properties of such Lyman break galaxies (LBGs) depend sensitively on the…

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

Generally the gas metallicity in distant galaxies can only be inferred by using a few prominent emission lines. Various theoretical models have been used to predict the relationship between emission line fluxes and metallicity, suggesting…

Astrophysics · Physics 2014-10-13 Tohru Nagao , Roberto Maiolino , Alessandro Marconi

We examine the redshift evolution of standard strong emission-line diagnostics for Hbeta-selected star-forming galaxies using the local SDSS sample and a new z = 0.2 - 2.3 sample obtained from HST WFC3 grism and Keck DEIMOS and MOSFIRE…

Astrophysics of Galaxies · Physics 2016-01-27 Lennox L. Cowie , Amy J. Barger , Antoinette Songaila

We investigate the evolution of the ionisation parameter of star-forming galaxies using a high-redshift ($z\sim 1.5$) sample from the FMOS-COSMOS survey and matched low-redshift samples from the Sloan Digital Sky Survey. By constructing…

Astrophysics of Galaxies · Physics 2018-05-01 Melanie Kaasinen , Lisa Kewley , Fuyan Bian , Brent Groves , Daichi Kashino , John Silverman , Jeyhan Kartaltepe

We derive new self-consistent theoretical UV, optical, and IR diagnostics for the ISM pressure and electron density in the ionized nebulae of star-forming galaxies. Our UV diagnostics utilize the inter-combination, forbidden and resonance…

The next generation of telescopes aim to directly observe the first generation of galaxies that initiated the reionization process in our Universe. The Lyman Alpha (Lya) emission line is robustly predicted to be the most prominent intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-16 Mark Dijkstra

The most passive galaxies at high redshift are unlikely to be identified by either narrow-band emission-line searches, or by Lyman limit searches (both techniques which have been highlighted at this meeting) simply because such selection…

Astrophysics · Physics 2007-05-23 James Dunlop

Context: Narrow-band surveys for Ly-alpha emitters (LAEs) is a powerful tool in detecting high, and very high, redshift galaxies. Even though samples are growing at redshifts z = 3 - 6, the nature of these galaxies is still poorly known.…

We utilize medium-resolution JWST/NIRSpec observations of 164 galaxies at $z=2.0-9.3$ from the Cosmic Evolution Early Release Science (CEERS) survey to investigate the evolution of the excitation and ionization properties of galaxies at…

Astrophysics of Galaxies · Physics 2023-01-18 Ryan L. Sanders , Alice E. Shapley , Michael W. Topping , Naveen A. Reddy , Gabriel B. Brammer

Recent ALMA measurements have revealed bright OIII 88 micron line emission from galaxies during the Epoch of Reionization (EoR) at redshifts as large as $z \sim 9$. We introduce an analytic model to help interpret these and other upcoming…

Astrophysics of Galaxies · Physics 2020-10-07 Shengqi Yang , Adam Lidz

We present results from a blind, spectroscopic survey for redshift ~5.7 Lyman-alpha-emitting galaxies using the Inamori Magellan Areal Camera and Spectrograph. A total of ~200 square arcminutes were observed in the COSMOS and LCIRS fields…

Astrophysics · Physics 2009-11-13 Crystal L. Martin , Marcin Sawicki , Alan Dressler , Pat McCarthy

High ionization star forming (SF) galaxies are easily identified with strong emission line techniques such as the BPT diagram, and form an obvious ionization sequence on such diagrams. We use a locally optimally emitting cloud model to fit…

We present a multiple emission lines study of $\sim$1300 H$\alpha$ emitters (HAEs) at $z \sim 2.3$ in the ZFOURGE survey. In contrast to the traditional spectroscopic method, our sample is selected based on the flux excess in the…