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Using the 3XMM catalogue of serendipitous X-ray sources, and the SDSS-DR9 spectroscopic catalogue, we have obtained a new sample of X-ray selected narrow emission line galaxies. The standard optical diagnostic diagram and selection by hard…

High Energy Astrophysical Phenomena · Physics 2014-09-05 Estelle Pons , Mike G. Watson

We derive the metallicity (traced by the O/H abundance) of the Narrow Line Region ( NLR) of 108 Seyfert galaxies as well as radial metallicity gradients along their galaxy disks and of these of a matched control sample of no active…

We present a coherent database of spectroscopic observations of far-IR fine-structure lines from the Herschel/PACS archive for a sample of 170 local AGN, plus a comparison sample of 20 starburst galaxies and 43 dwarf galaxies. Published…

Astrophysics of Galaxies · Physics 2016-10-19 J. A. Fernández-Ontiveros , L. Spinoglio , M. Pereira-Santaella , M. A. Malkan , P. Andreani , K. M. Dasyra

We present the results of Hi line observations towards 26 Active Galactic Nuclei (AGN)-hosting and one star-forming dwarf galaxies (Mstar < 10^9.5 Msun) with the 19-beam spectral line receiver of FAST at 1.4 GHz. Our FAST observed targets…

Astrophysics of Galaxies · Physics 2025-12-01 Hong-Ying Chen , Chao-Wei Tsai , Pei Zuo , Niankun Yu , Jialai Wang , Kai Zhang , Guodong Li , Yogesh Chandola , Zheng Zheng , Jingwen Wu , Di Li , Lulu Bao

We present long slit optical spectroscopy of 67 HII regions in 21 dwarf irregular galaxies to investigate the enrichment of oxygen, nitrogen, neon, sulfur, and argon in low mass galaxies. Oxygen abundances are obtained via direct detection…

Astrophysics · Physics 2009-11-13 L. van Zee , M. P. Haynes

We present a new sample of 116 double-peaked Balmer line Active Galactic Nuclei (AGN) selected from the Sloan Digital Sky Survey. Double-peaked emission lines are believed to originate in the accretion disks of AGN, a few hundred…

Astrophysics · Physics 2009-09-29 Iskra V. Strateva , Michael A. Strauss , Lei Hao , David J. Schlegel

We present new upper limits on the neutral hydrogen (HI) content within the stellar half-light ellipses of 15 Galactic dwarf spheroidal galaxies (dSphs), derived from pointed observations with the Green Bank Telescope (GBT) as well as…

Astrophysics of Galaxies · Physics 2015-06-23 K. Spekkens , N. Urbancic , B. S. Mason , B. Willman , J. E. Aguirre

We present evidence for unusually strong Halpha emission in galaxies with spectroscopic redshifts in the range of 3.8<z<5.0, over the Great Observatories Origins Deep Survey (GOODS) fields. Among 74 galaxies detected in the Spitzer IRAC 3.6…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Hyunjin Shim , Ranga-Ram Chary , Mark Dickinson , Lihwai Lin , Hyron Spinrad , Daniel Stern , Chi-Hung Yan

The James Webb Space Telescope (JWST) has enabled us to uncover faint galaxies and active galactic nuclei (AGNs) in the early universe. Taking advantage of the unique filter combination used in the Cosmic Evolution Early Release Science…

Although it is well known that massive galaxies have central black holes, most of them accreting at low Eddington ratios, many important questions still remain open. Among them, are the nature of the ionizing source, the characteristics and…

Astrophysics of Galaxies · Physics 2015-06-19 T. V. Ricci , J. E. Steiner , R. B. Menezes

We analysed the nuclear region of all 56 early-type galaxies from the DIVING$^\mathrm{3D}$ Project, which is a statistically complete sample of objects that contains all 170 galaxies of the Southern Hemisphere with B < 12.0 mag and galactic…

Astrophysics of Galaxies · Physics 2023-04-28 T. V. Ricci , J. E. Steiner , R. B. Menezes , K. Slodkowski Clerici , M. D. da Silva

We use time-domain optical spectroscopy to distinguish between broad emission lines powered by accreting black holes (BHs) or stellar processes (i.e., supernovae) for 16 galaxies identified as AGN candidates by Reines \etal (2013). Our…

(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 review ASCA results on a search for low luminosity active nuclei at the center of nearby normal galaxies. More than a dozen low-luminosity AGN have been discovered with 2-10 keV luminosity in the range 10^{40-41} ergs/s. Their X-ray…

Astrophysics · Physics 2007-05-23 Y. Terashima

We have used the VIMOS integral field spectrograph to map the emission line properties in a sample of 24 star forming galaxies selected from the SDSS database. In this data paper we present and describe the sample, and explore some basic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 J. Gerssen , D. J. Wilman , L. Christensen

We present infrared, optical, and X-ray data of 48 X-ray bright, optically dull AGNs in the COSMOS field. These objects exhibit the X-ray luminosity of an active galactic nucleus (AGN) but lack broad and narrow emission lines in their…

We present X-ray and multiwavelength studies of a sample of eight high-luminosity active galactic nuclei (AGNs) with disc-like H\beta emission-line profiles selected from the Sloan Digital Sky Survey Data Release 7. These sources have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 B. Luo , W. N. Brandt , M. Eracleous , Jian Wu , P. B. Hall , A. Rafiee , D. P. Schneider , Jianfeng Wu

We present a spectroscopic study of the incidence of AGN nuclear activity in two samples of isolated galaxies (Karachentseva, V.E. & Varela, J.). Our results show that the incidence of non-thermal nuclear activity is about 43% and 31% for…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Francisco Hernandez-Ibarra , Deborah Dultzin , Yair Krongold , Ascencion Del Olmo , Jaime Perea , Jesus Gonzalez

The massive black hole (BH) population in dwarf galaxies ($M_{\rm BH} \lesssim 10^5~M_\odot$) can provide strong constraints on the origin of BH seeds. However, traditional optical searches for active galactic nuclei (AGNs) only reliably…

Astrophysics of Galaxies · Physics 2022-06-24 M. Molina , A. E. Reines , L. J. Latimer , V. Baldassare , Sheyda Salehirad