English
Related papers

Related papers: The distance of quasar outflows from the central s…

200 papers

Spectroscopic observations of quasar outflows at rest-frame 500-1000 Angstrom have immense diagnostic power. We present analyses of such data, where absorption troughs from three important ions are measured: first, O IV and O IV* that allow…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Nahum Arav , Benoit Borguet , Carter Chamberlain , Doug Edmonds , Charles Danforth

Determining the distance of quasar absorption outflows from the central source (R) and their kinetic luminosity are crucial for understanding their contribution to active galactic nucleus (AGN) feedback. Here we summarize the results for a…

Astrophysics of Galaxies · Physics 2020-10-07 Timothy R. Miller , Nahum Arav , Xinfeng Xu , Gerard A. Kriss

The most robust way for determining the distance of quasar absorption outflows is the use of troughs from ionic excited states. The column density ratio between the excited and resonance states yields the outflow number density. Combined…

Astrophysics of Galaxies · Physics 2019-05-14 Nahum Arav , Guilin Liu , Xinfeng Xu , James Stidham , Chris Benn , Carter Chamberlain

Absorption outflows in quasars play an important role in understanding active galactic nuclei (AGN) feedback and their influence on galaxy evolution. The unprecedented spectral data provided by the Dark Energy Spectroscopic Instrument…

Astrophysics of Galaxies · Physics 2025-06-02 Maryam Dehghanian , Nahum Arav , Mayank Sharma , Gwen Walker , Kyle Johnston , Matthew Kaupin , Justin Gandhi

Quasar outflows carry mass, momentum and energy into the surrounding environment, and have long been considered a potential key factor in regulating the growth of supermassive black holes and the evolution of their host galaxies. A crucial…

From Hubble Space Telescope/Cosmic Origins Spectrograph spectra of five quasars, 16 outflows are detected. For 11 outflows, we are able to constrain their distances to the central source (R) and their energetics. In instances of multiple…

Astrophysics of Galaxies · Physics 2020-07-22 Timothy R. Miller , Nahum Arav , Xinfeng Xu , Gerard Kriss , Rachel Plesha

We conducted a survey of quasar outflows using the VLT/X-shooter spectrograph. When choosing the 14 BAL and mini-BALs comprising this sample, the data did not cover the S IV and S IV* troughs, whose ratio can be used to determine the…

Astrophysics of Galaxies · Physics 2019-05-14 Xinfeng Xu , Nahum Arav , Timothy Miller , Chris Benn

The Hubble Space Telescope/Cosmic Origins Spectrograph (COS) has opened a new discovery space for studying quasar absorption outflows and their contribution to AGN feedback. Specifically, COS provides high-quality far-ultraviolet (FUV)…

Astrophysics of Galaxies · Physics 2020-03-20 Nahum Arav , Xinfeng Xu , Timothy R. Miller , Gerard A. Kriss , Rachel J. Plesha

Quasar outflows can play a crucial role in the evolution of their host galaxies through various feedback processes. This effect is expected to be particularly important when the universe was only 2-3 billion years old, during the period…

Astrophysics of Galaxies · Physics 2025-08-13 Mayank Sharma , Nahum Arav , Maryam Dehghanian , Gwen Walker , Kyle Johnston , Matthew Kaupin , Justin Gandhi

AGN-driven outflows are invoked by galaxy evolutionary models to quench star formation and to explain the origin of the relations observed locally between super massive black holes and their host galaxies. This work aims to detect the…

Aims. Outflows from active galactic nuclei are invoked as the principal feedback process regulating the co-evolution of supermassive black holes and their host galaxies. Because of their multi-phase and multi-scale nature, an exhaustive…

We consider if outflowing winds that are detected via narrow absorption lines (NALs) with FWHM of $<$ 500 km/s (i.e., NAL outflows) in quasar spectra contribute to feedback. As our sample, we choose 11 NAL systems in eight optically…

Astrophysics of Galaxies · Physics 2025-08-01 Toru Misawa , Jane C. Charlton , Michael Eracleous

We present the analysis of two outflows (S1 at --5500 km s$^{-1}$ and S2 at --9700 km s$^{-1}$) seen in recent HST/COS observations of quasar SDSS J0755+2306 (z = 0.854). The outflows are detected as absorption troughs from both…

Astrophysics of Galaxies · Physics 2020-03-25 Xinfeng Xu , Nahum Arav , Timothy Miller , Gerard A. Kriss , Rachel Plesha

We detect four very energetic outflows in the Hubble Space Telescope/Cosmic Origin Spectrograph spectra of quasar 2MASS J1051+1247 with a combined kinetic luminosity ($\dot{E_k}$) of 10$^{46}$ erg s$^{-1}$. Remarkable similarities are seen…

Astrophysics of Galaxies · Physics 2020-03-20 Timothy R. Miller , Nahum Arav , Xinfeng Xu , Gerard A. Kriss , Rachel J. Plesha

We present observations of ionized gas outflows in eleven z$ =1.39-2.59$ radio-loud quasar host galaxies. Data was taken with the integral field spectrograph (IFS) OSIRIS and the adaptive optics system at the W.M. Keck Observatory targeting…

Quasar feedback is routinely invoked as an indispensable ingredient in galaxy formation models. Galactic outflows are a crucial agent of quasar feedback that frequently manifest themselves in absorption and emission lines. Measuring the…

Astrophysics of Galaxies · Physics 2025-02-27 Qinyuan Zhao , Luming Sun , Lu Shen , Guilin Liu , Junfeng Wang , Mayank Sharma , Nahum Arav , Yulong Gao , Chris Benn

We present the analysis of the absorption troughs of six outflows observed in quasar SDSS J1130+0411 ($z \approx 3.98$) with radial velocities ranging from $-2400$ to $-15,400$ km s$^{-1}$. These spectra were taken with the Very Large…

Astrophysics of Galaxies · Physics 2022-09-22 Andrew Walker , Nahum Arav , Doyee Byun

The aim of this paper is to test the basic model of negative AGN feedback. According to this model, once the central black hole accretes at the Eddington limit and reaches a certain critical mass, AGN driven outflows blow out gas,…

Astrophysics of Galaxies · Physics 2016-01-13 B. Balmaverde , A. Marconi , M. Brusa , S. Carniani , G. Cresci , E. Lusso , R. Maiolino , F. Mannucci , T. Nagao

Outflows from active galactic nuclei (AGNs) seem to be common and are thought to be important from a variety of perspectives: as an agent of chemical enhancement of the interstellar and intergalactic media, as an agent of angular momentum…

Astrophysics · Physics 2009-11-13 Rajib Ganguly , Michael S. Brotherton

Quasar outflows may play a crucial role in regulating the host galaxy, although the spatial scale of quasar outflows remain a major enigma, with their acceleration mechanism poorly understood. The kinematic information of outflow is the key…

‹ Prev 1 2 3 10 Next ›