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相关论文: CLASSY XIV: The Nitrogen Exception -- Multi-Phase …

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Sensitive measurements of the interstellar gas-phase oxygen abundance have revealed a slight oxygen deficiency ($\sim$ 15%) toward stars within 500 pc of the Sun as compared to more distant sightlines. Recent $FUSE$ observations of the…

天体物理学 · 物理学 2009-11-11 David C. Knauth , James T. Lauroesch , David M. Meyer

We present spectra obtained with the 10.4 m Gran Telescopio Canarias telescope of 13 Galactic HII regions, most of them of very low ionisation degree. The objects are located along the Galactic disc, with R_G from 5.7 to 16.1 kpc. We…

星系天体物理 · 物理学 2018-05-16 C. Esteban , J. Garcia-Rojas

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…

星系天体物理 · 物理学 2018-09-05 Renbin Yan

We present observations with the Space Telescope Imaging Spectrograph (STIS) onboard the Hubble Space Telescope of eleven Lyman continuum (LyC) leaking galaxies at redshifts, z, in the range 0.29-0.43, with oxygen abundances…

星系天体物理 · 物理学 2023-04-20 Y. I. Izotov , D. Schaerer , G. Worseck , D. Berg , J. Chisholm , S. Ravindranath , T. X. Thuan

We present a detailed spectroscopic analysis of nitrogen abundances in 91 solar-type stars, 66 with and 25 without known planetary mass companions. All comparison sample stars and 28 planet hosts were analysed by spectral synthesis of the…

天体物理学 · 物理学 2016-08-16 A. Ecuvillon , G. Israelian , N. C. Santos , M. Mayor , R. J. García López , S. Randich

For the first time, a direct NLTE analysis of carbon and nitrogen lines in the spectra of nine RR Lyrae stars was carried out. We have determined the abundances of these elements together with oxygen, and have shown that the nitrogen…

太阳与恒星天体物理 · 物理学 2021-10-04 Sergei M. Andrievsky , Sergey A. Korotin , Valery V. Kovtyukh , Sergey V. Khrapaty , Yuri Rudyak

We present spatially-resolved measurements of the ionized gas masses and mass outflow rates for six low-redshift ($z \leq$ 0.02) active galaxies. In this study, we expand our sample to galaxies with more complex gas kinematics modeled as…

We employ the high-redshift suite of FIRE-2 cosmological hydrodynamic zoom-in simulations to investigate the evolution of gas-phase metallicity radial gradients in galaxies in the epoch of reionization (EoR). Our sample consists of 22…

The chemical evolution of galaxies on a cosmological timescale is still a matter of debate despite the increasing number of available data provided by spectroscopic surveys of star-forming galaxies at different redshifts. The fundamental…

We have determined the O/H and N/O of a sample of 122751 SFGs from the DR7 of the SDSS. For all these galaxies we have also determined their morphology and their SFH using the code STARLIGHT. The comparison of the chemical abundance with…

宇宙学与河外天体物理 · 物理学 2015-06-05 J. P. Torres-Papaqui , R. Coziol , R. A. Ortega-Minakata , D. M. Neri-Larios

We present a sample of 42 high-mass low-metallicity outliers from the mass--metallicity relation of star-forming galaxies. These galaxies have stellar masses that span log(M_*/M_sun) ~9.4 to 11.1 and are offset from the mass--metallicity…

天体物理学 · 物理学 2011-02-11 Molly S. Peeples , Richard W. Pogge , K. Z. Stanek

Galaxy chemical enrichment mechanisms have primarily been constrained by [$\alpha$/Fe] and [Fe/H] measurements of individual stars and integrated light from stellar populations. However such measurements are limited at higher redshifts…

星系天体物理 · 物理学 2025-03-27 Souradeep Bhattacharya , Magda Arnaboldi , Ortwin Gerhard , Chiaki Kobayashi , Kanak Saha

We present analyses of a nitrogen-enriched star-forming galaxy, ID60001, at $z=4.6928$ based on JWST/NIRSpec MSA spectroscopy and NIRCam photometry. From rest-frame optical emission lines we derive the nitrogen-to-oxygen (N/O) abundance…

星系天体物理 · 物理学 2025-02-10 Yechi Zhang , Takahiro Morishita , Massimo Stiavelli

Using the near-IR spectroscopy of the MOSFIRE Deep Evolution Field (MOSDEF) survey, we investigate the role of local environment in the gas-phase metallicity of galaxies. The local environment measurements are derived from accurate and…

We present 4 new measurements of nitrogen abundances and one upper limit in damped Lyman alpha absorbers (DLAs) obtained by means of high resolution (FWHM \~ 7 km/s) UVES/VLT spectra. In addition to these measurements we have compiled data…

天体物理学 · 物理学 2011-05-23 M. Centurion , P. Molaro , G. Vladilo , C. Peroux , S. A. Levshakov , V. D'Odorico

The metal enrichment of a galaxy is determined by the cycle of baryons in outflows, inflows, and star formation. The relative contribution and timescale of each process sets the relationship between stellar mass, metallicity, and the star…

We determined C, N and alpha-element relative abundances in the gas surrounding six QSOs at an average redshift of < z > ~ 2.4, by studying six narrow associated absorption systems in UVES high-resolution spectra. We found five systems with…

New abundances of N, O, Na, Mg, Si, Ca, Sc, Ti, Cr, Fe, Sr, Zr, and Ba are presented for 10 A-type supergiants in the SMC, plus upper limits for C. In interpreting the CNO results for constraints on stellar evolution theories, careful…

天体物理学 · 物理学 2009-06-16 Kim Venn

The combination of gas-phase oxygen abundances and stellar metallicities can provide us with unique insights into the metal enrichment histories of galaxies. In this work, we compare the stellar and gas-phase metallicities measured within a…

We present new and archival SOFIA FIFI-LS far-IR spectroscopic observations of 25 local galaxies of either the [OIII]52um and/or the [NIII]57um lines. Including other 31 galaxies from Herschel-PACS, we discuss a local sample of 47 galaxies,…

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