A5051101155- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Diabetes Treatment and Management
- Italian Fascism and Post-war Society
- Diabetes Management and Research
- Scientific Research and Discoveries
- Dark Matter and Cosmic Phenomena
- Geophysics and Gravity Measurements
- Adaptive optics and wavefront sensing
- Statistics Education and Methodologies
- Astronomical Observations and Instrumentation
- Black Holes and Theoretical Physics
- Nutritional Studies and Diet
- Pulsars and Gravitational Waves Research
- Metabolism, Diabetes, and Cancer
- Diabetes Management and Education
- Advanced Mathematical Theories and Applications
- Italian Literature and Culture
Diego Portales University
2022-2024
European Southern Observatory
2018-2023
University of Central Florida
2014-2023
Max Planck Institute for Astronomy
2015-2019
Max Planck Society
2014-2019
Ospedale Policlinico San Martino
2015-2018
Heidelberg University
2017
University of Ferrara
2017
University of Genoa
2014-2015
University of Milan
2014
Distant quasars are unique tracers to study the formation of earliest supermassive black holes (SMBHs) and history cosmic reionization. Despite extensive efforts, only two have been found at $z\ge7.5$, due a combination their low spatial density high contamination rate in quasar selection. We report discovery luminous $z=7.642$, J0313$-$1806, most distant yet known. This has bolometric luminosity $3.6\times10^{13} L_\odot$. Deep spectroscopic observations reveal SMBH with mass $(1.6\pm0.4)...
We present a survey of the [CII] 158 $\mu$m line and underlying far-infrared (FIR) dust continuum emission in sample 27 z>6 quasars using Atacama Large Millimeter Array (ALMA) at ~1" resolution. The was significantly detected (at >5-sigma) 23 sources (85%). find typical luminosities $L_{\rm [CII]}=10^{9-10}$ L$_\odot$, an average width ~385 km/s. [CII]-to-far-infrared luminosity ratio ([CII]/FIR) our span one order magnitude, highlighting variety conditions star-forming medium. Four quasar...
Abstract Quasars are galaxies hosting accreting supermassive black holes; due to their brightness, they unique probes of the early universe. To date, only a few quasars have been reported at <?CDATA $z\gt 6.5$?> (<800 Myr after big bang). In this work, we present six additional $z\gtrsim discovered using Pan-STARRS1 survey. We use sample 15 perform homogeneous and comprehensive analysis highest-redshift quasar population. report four main results: (1) majority show large blueshifts broad...
Abstract During reionization, neutral hydrogen in the intergalactic medium (IGM) imprints a damping wing absorption feature on spectrum of high-redshift quasars. A detection this signature provides compelling evidence for significantly universe, and enables measurements fraction x H i ( z ) at that epoch. Obtaining reliable quantitative constraints from technique, however, is challenging due to stochasticity induced by patchy inside-out topology degeneracies with quasar lifetime, unknown...
ABSTRACT Luminous quasars at <?CDATA $z\gt 5.6$?> can be studied in detail with the current generation of telescopes and provide us unique information on first gigayear universe. Thus far, these studies have been statistically limited by number known redshifts. Such are rare, therefore, wide-field surveys required to identify them, multiwavelength data separate them efficiently from their main contaminants, far more numerous cool dwarfs. In this paper, we update extend selection for $z\sim...
We present measurements of black hole masses and Eddington ratios for a sample 38 bright (M$_{1450}$ < -24.4 mag) quasars at 5.8 z 7.5, derived from VLT/X-shooter near-IR spectroscopy their broad CIV MgII emission lines. The (on average M$_{BH}$ ~ 4.6 x 10$^9$ M$_{\odot}$) accretion rates (with ranging between 0.1 1.0) are broadly consistent with that similarly luminous 0.3 2.3 quasars, but there is evidence mild increase in the median ratio going towards > 6. Combined deep ALMA observations...
We present the first results from JWST ASPIRE program (A SPectroscopic survey of biased halos In Reionization Era). This represents an imaging and spectroscopic 25 reionization-era quasars their environments by utilizing unprecedented capabilities NIRCam Wide Field Slitless Spectroscopy (WFSS) mode. will deliver largest ($\sim280~{\rm arcmin}^2$) galaxy redshift at 3-4 $\mu$m among Cycle-1 programs provide extensive legacy values for studying formation earliest supermassive black holes...
Abstract The variations in Ly α forest opacity observed at z > 5.3 between lines of sight to different background quasars are too strong be caused by fluctuations the density field alone. leading hypothesis for cause this excess variance is a late, ongoing reionization process redshifts below six. Another model proposes ionizing coupled short, spatially varying mean free path photons, without explicitly invoking incomplete reionization. With recent observations suggesting short ∼ 6, and...
Abstract We present in this paper (Paper II of the series) a 35 arcmin 2 JWST/NIRCam imaging and wide-field slitless spectroscopy mosaic centered on J0305–3150, luminous quasar at z = 6.61. The F356W grism data reveal 124 [O iii ]+H β emitters 5.3 < 7, 53 which constitute protocluster spanning (10 cMpc) across 6.5 6.8. find no evidence any broad-line active galactic nucleus (AGN) individual galaxies or stacking, reporting median H FWHM 585 ± 152 km s −1 ; however, mass–excitation diagram...
Abstract A SPectroscopic survey of bIased halos in the Reionization Era is a quasar legacy primarily using JWST to target sample 25 z > 6 quasars with NIRCam slitless spectroscopy and imaging. The first study this series found evidence strong overdensity galaxies around J0305−3150, luminous at = 6.61, within single pointing obtained Cycle 1. Here we present results 2 mosaic that covers 35 arcmin imaging/wide-field same field investigate spatial extent putative protocluster. F356W grism...
Background. Primary Sjögren's syndrome is a connective tissue disorder affecting primarily the lacrimal and salivary glands, resulting in xerophtalmia xerostomia. Extraglandular manifestations are frequent may include renal involvement.
Luminous distant quasars are unique probes of the high-redshift intergalactic medium (IGM) and growth massive galaxies black holes in early universe. Absorption due to neutral hydrogen IGM makes beyond a redshift very faint optical z band, thus locating at higher redshifts requires large surveys that sensitive above 1 micron. We report discovery three new quasars, corresponding an age universe Myr, selected as z-band dropouts Pan-STARRS1 survey. This increases number known from four seven....
Abstract We study quasar proximity zones in the redshift range <?CDATA $5.77\leqslant z\leqslant 6.54$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>5.77</mml:mn> <mml:mo>≤</mml:mo> <mml:mi>z</mml:mi> <mml:mn>6.54</mml:mn> </mml:math> by homogeneously analyzing 34 medium-resolution spectra, encompassing both archival and newly obtained data, exploiting recently updated systemic magnitude measurements. Whereas previous studies found strong evolution of...
We present IRAM/NOEMA and JVLA observations of the quasar J1342+0928 at z=7.54 report detections copious amounts dust [CII] emission in interstellar medium (ISM) its host galaxy. At this redshift, age universe is 690 Myr, about 10% younger than redshift previous record holder. Yet, ISM new galaxy significantly enriched by metals, as evidenced detection 158micron cooling line underlying far-infrared (FIR) continuum emission. To first order, FIR properties are similar to those found a slightly...
We present a study of the [CII] 158micron line and underlying far-infrared (FIR) continuum emission 27 quasar host galaxies at z~6, traced by Atacama Large Millimeter/submillimeter Array spatial resolution ~1 physical kpc. The in bright, central regions quasars have sizes 1.0-4.8kpc. dust is typically more compact than [CII]. find that 13/27 (approximately one-half) companion field, projected separations 3-90kpc. position Gaia-corrected positions accreting black holes are cospatial (typical...
We present Atacama Large Millimeter Array 1mm observations of the rest-frame far-infrared (FIR) dust continuum in 27 quasars at redshifts 6.0 < z 6.7. detect FIR emission >3sigma all quasar host galaxies with flux densities ~1900GHz 0.12 S_rest,1900GHz 5.9mJy, a median (mean) density 0.88mJy (1.59mJy). The implied luminosities range from L_FIR = (0.27-13)x10^12 L_sun, 74% our hosts having > 10^12 L_sun. estimated masses are M_dust 10^7-10^9 M_sun. If is heated only by star formation, then...
We use ALMA observations of the host galaxy quasar ULAS-J1342+0928 at z=7.54 to study dust continuum and far infrared lines emitted from its interstellar medium. The Rayleigh-Jeans tail is well sampled with eight different spectral setups, a modified black body fit we obtain an emissivity coefficient beta=1.85+-0.3. Assuming standard temperature 47 K derive mass Mdust=0.35x10^8 Msol star formation rate 150+-30 Msol/yr. have >4sigma detections [CII]_158, [OIII]_88 [NII]_122 atomic fine...
Abstract Radio sources at the highest redshifts can provide unique information on first massive galaxies and black holes, densest primordial environments, epoch of reionization. The number astronomical objects identified z > 6 has increased dramatically over last few years, but previously only three radio-loud ( R 2500 = f ν ,5 GHz / ,2500 Å 10) had been reported 6, with most distant being a quasar 6.18. Here we present discovery characterization PSO J172.3556+18.7734, 6.823. This source...
Studies of rest-frame optical emission in quasars at $z>6$ have historically been limited by the wavelengths accessible ground-based telescopes. The James Webb Space Telescope (JWST) now offers opportunity to probe this deep into reionization epoch. We report observations eight $z>6.5$ using JWST/NIRCam Wide Field Slitless Spectroscopy, as a part ''A SPectroscopic survey biased halos In Reionization Era (ASPIRE)" program. Our JWST spectra cover quasars' between rest frame $\sim$ 4100 and...
Abstract The identification of bright quasars at z ≳ 6 enables detailed studies supermassive black holes, massive galaxies, structure formation, and the state intergalactic medium within first billion years after Big Bang. We present spectroscopic confirmation 55 redshifts 5.6 < 6.5 UV magnitudes −24.5 M 1450 −28.5 identified in optical Pan-STARRS1 near-IR VIKING surveys (48 7, respectively). Five these have independently been discovered other studies. quasar sample shows an extensive...
We present bolometric luminosities, black hole masses and Eddington ratios for 42 luminous quasars at z>6 using high signal-to-noise ratio VLT/X-Shooter spectra, acquired in the enlarged ESO Large Programme XQR-30. In particular, we derive luminosities from rest-frame 3000 A, a correction literature, by modelling spectral regions around CIV 1549A MgII 2798A emission lines, with scaling relations calibrated local universe. find that derived both lines are same range, scatter of measurements...
Abstract We present the z ≈ 6 type-1 quasar luminosity function (QLF), based on Pan-STARRS1 (PS1) survey. The PS1 sample includes 125 quasars at 5.7–6.2, with −28 ≲ M 1450 −25. With addition of 48 fainter from SHELLQs survey, we evaluate QLF over −22. Adopting a double power law an exponential evolution density (Φ( ) ∝ 10 k ( −6) ; = −0.7), use maximum likelihood method to model our data. find break magnitude <?CDATA ${M}^{* }=-{26.38}_{-0.60}^{+0.79}\,\mathrm{mag}$?> <mml:math...