相关论文: An ultra-dense fast outflow in a quasar at z=2.4

We present discovery spectra of a sample of eight lensed galaxies at high redshift, 3.7<z<5.2, selected by their red colors in the fields of four massive clusters: A1689, A2219, A2390, and AC114. Metal absorption lines are detected and…

The quasar SDSS 0956+5128 exhibits three distinct velocity components with large offsets in emission: the systemic velocity of [O II], [O III] and [Ne III] narrow lines have redshift $z=0.7142$; broad Mg II line is shifted by $-1200$ km…

In this paper, we provide new 1 Ms $Chandra$ ACIS spectra of two quasars in the Chandra Deep Field South (CDF-S), which were previously reported to show strong and extremely blueshifted X-ray emission/absorption line features in previous 1…

We investigate possible factors that drive fast quasar outflows using a sample of 39,249 quasars at median redshift $\langle z \rangle \approx$ 2.17. Unique to this study, the quasar redshifts are re-measured based on the Mg II emission…

Gaseous outflows appear to be a universal property of type-1 and type-2 active galactic nuclei (AGN). The main diagnostic is provided by emission features shifted to higher frequency via the Doppler effect, implying that the emitting gas is…

Many theoretical models predict that quasar driven outflows account for the observed quenching of star formation in massive galaxies. There is growing observational evidence for quasar-launched massive outflows at z>6, while the details of…

We present an observational study of 22 broad absorption line quasars (BAL QSOs) at $3\lesssim z \lesssim5$ based on optical/near-IR spectroscopy, aiming to investigate quasar winds and their effects. The near-IR spectroscopy covers the…

Using data from SDSS, UKIDSS and WISE, we investigate the properties of the high-frequency cutoff to the infrared emission in $\simeq$5000 carefully selected luminous ($L_{bol} \simeq 10^{47}$) type 1 quasars. The strength of $\simeq$2…

Quasar outflows may play important role in the evolution of its host galaxy and central black hole. In this paper, we present a detailed study of multiple outflows in the obscured ultra-luminous infrared quasar Q1321+058. The outflows…

We present near-IR, low resolution spectra of eight of the most distant quasars known, with redshifts in the range 4.9<z<6.4. Half of these quasars are characterized by deep, broad and blueshifted absorption features associated with both…

We present the first near-infrared interferometric data of a QSO at z=4. The K-band observations were performed with GRAVITY+ on the VLTI using all four UTs, detecting a differential phase signal that traces the spatially resolved…

We report the discovery of highly reddening and hydrogen Balmer and metastable helium broad absorption lines in the quasar SDSS J145057.28+530007.6, based on the optical and near-infrared spectra taken from the SDSS-III/BOSS and the…

Quasars accreting at very high rates are believed to be prime movers of galactic evolution because of their high radiative and mechanical output. The study presented in this paper investigates a sample of six highly accreting quasars at…

Broad absorption line quasars are among the objects presenting the fastest outflows. The launching mechanism itself is not completely understood. Models in which they could be launched from the accretion disk, and then curved and…

We report the detection of OH 1667 MHz and wide HI 21cm absorption at $z \sim 0.67$ towards the red quasar 1504+377, with the Green Bank Telescope and the Giant Metrewave Radio Telescope. The HI 21cm absorption extends over a velocity range…

We present a detailed study of the optical and NIR emission and absorption line spectrum of the quasar SDSS J163345.22+512748.4. We discovered on the newly acquired NIR spectrum a highly meta-stable neutral helium broad absorption line…

4C 71.07 is a high-redshift blazar whose optical radiation is dominated by quasar-like nuclear emission. We here present the results of a spectroscopic monitoring of the source to study its unbeamed properties. We obtained 24 optical…

Some cosmological hydrodynamical simulations predict that outflows driven by active galactic nuclei (AGN) play a key role in powering the Ly$\alpha$ nebulae observed around high-redshift quasars. In such simulations, AGN feedback seeded as…

We report on the discovery of a rare case of spatially and kinematically resolved galactic scale outflow at intermediate redshift, based on VLT/MUSE optical integral field spectroscopic observation of the quasar HE 0238$-$1904. This…

Observational evidence revealing the main mechanisms that accelerate quasar outflows has proven difficult to obtain, due to the complexity of the absorption features that this gas produces in the spectra of the emission sources. We build 36…