DSpace Angular :: Browsing by Author "Lanzuisi, G."

Browsing by Author "Lanzuisi, G."

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An X-ray fading, UV brightening QSO at z ≈ 6
(2022) Vito, F.; Mignoli, M.; Gilli, R.; Brandt, W. N.; Shemmer, O.; Bauer, F. E.; Bisogni, S.; Luo, B.; Marchesi, S.; Nanni, R.; Zamorani, G.; Comastri, A.; Cusano, F.; Gallerani, S.; Vignali, C.; Lanzuisi, G.
Explaining the existence of super massive black holes (SMBHs) with M-BH greater than or similar to 10(8) M-circle dot at z greater than or similar to 6 is a persistent challenge to modern astrophysics. Multiwavelength observations of z greater than or similar to 6 quasi-stellar objects (QSOs) reveal that, on average, their accretion physics is similar to that of their counterparts at lower redshift. However, QSOs showing properties that deviate from the general behavior can provide useful insights into the physical processes responsible for the rapid growth of SMBHs in the early universe. We present X-ray (XMM-Newton, 100 ks) follow-up observations of a z approximate to 6 QSO, J1641+3755, which was found to be remarkably X-ray bright in a 2018 Chandra dataset. J1641+3755 is not detected in the 2021 XMM-Newton observation, implying that its X-ray flux decreased by a factor greater than or similar to 7 on a notably short timescale (i.e., approximate to 115 rest-frame days), making it the z > 4 QSO with the largest variability amplitude. We also obtained rest-frame ultraviolet (UV) spectroscopic and photometric data with the Large Binocular Telescope (LBT). Surprisingly, comparing our LBT photometry with archival data, we found that J1641+3755 became consistently brighter in the rest-frame UV band from 2003 to 2016, while no strong variation occurred from 2016 to 2021. Its rest-frame UV spectrum is consistent with the average spectrum of high-redshift QSOs. Multiple narrow absorption features are present, and several of them can be associated with an intervening system at z = 5 :67. Several physical causes can explain the variability properties of J1641+3755, including intrinsic variations of the accretion rate, a small-scale obscuration event, gravitational lensing due to an intervening object, and an unrelated X-ray transient in a foreground galaxy in 2018. Accounting for all of the z > 6 QSOs with multiple X-ray observations separated by more that ten rest-frame days, we found an enhancement of strongly (i.e., by a factor >3) X-ray variable objects compared to QSOs at later cosmic times. This finding may be related to the physics of fast accretion in high-redshift QSOs.
Connecting X-ray nuclear winds with galaxy-scale ionised outflows in two z ∼ 1.5 lensed quasars
(2021) Tozzi, G.; Cresci, G.; Marasco, A.; Nardini, E.; Marconi, A.; Mannucci, F.; Chartas, G.; Rizzo, F.; Amiri, A.; Brusa, M.; Comastri, A.; Dadina, M.; Lanzuisi, G.; Mainieri, V.; Mingozzi, M.; Perna, M.; Venturi, G.; Vignali, C.
Aims. Outflows driven by active galactic nuclei (AGN) are expected to have a significant impact on host galaxy evolution, but the matter of how they are accelerated and propagated on galaxy-wide scales is still under debate. This work addresses these questions by studying the link between X-ray, nuclear ultra-fast outflows (UFOs), and extended ionised outflows, for the first time, in two quasars close to the peak of AGN activity (z similar to 2), where AGN feedback is expected to be more effective.Methods. Our selected targets, HS 0810+2554 and SDSS J1353+1138, are two multiple-lensed quasars at z similar to 1.5 with UFO detection that have been observed with the near-IR integral field spectrometer SINFONI at the VLT. We performed a kinematical analysis of the [O III]lambda 5007 optical emission line to trace the presence of ionised outflows.Results. We detected spatially resolved ionised outflows in both galaxies, extended more than 8 kpc and moving up to v>2000 km s(-1). We derived mass outflow rates of similar to 12 M-circle dot yr(-1) and similar to 2 M-circle dot yr(-1) for HS 0810+2554 and SDSS J1353+1138.Conclusions. Compared with the co-hosted UFO energetics, the ionised outflow energetics in HS 0810+2554 is broadly consistent with a momentum-driven regime of wind propagation, whereas in SDSS J1353+1138, it differs by about two orders of magnitude from theoretical predictions, requiring either a massive molecular outflow or a high variability of the AGN activity to account for such a discrepancy. By additionally considering our results together with those from the small sample of well-studied objects (all local but one) having both UFO and extended (ionised, atomic, or molecular) outflow detections, we found that in 10 out of 12 galaxies, the large-scale outflow energetics is consistent with the theoretical predictions of either a momentum- or an energy-driven scenario of wind propagation. This suggests that such models explain the acceleration mechanism of AGN-driven winds on large scales relatively well.
Discovery of a galaxy overdensity around a powerful, heavily obscured FRII radio galaxy at z=1.7: star formation promoted by large-scale AGN feedback?
(2019) Gilli, R.; Mignoli, M.; Peca, A.; Nanni, R.; Prandoni, I.; Liuzzo, E.; D'Amato, Q.; Brusa, M.; Calura, F.; Caminha, G. B.; Chiaberge, M.; Comastri, A.; Cucciati, O.; Cusano, F.; Grandi, P.; Decarli, R.; Lanzuisi, G.; Mannucci, F.; Pinna, E.; Tozzi, P.; Vanzella, E.; Vignali, C.; Vito, F.; Balmaverde, B.; Citro, A.; Cappelluti, N.; Zamorani, G.; Norman, C.
We report the discovery of a galaxy overdensity around a Compton-thick Fanaroff-Riley type II (FRII) radio galaxy at z = 1:7 in the deep multiband survey around the z = 6.3 quasi-stellar object (QSO) SDSS J1030 +0524. Based on a 6 h VLT/MUSE and on a 4 h LBT/LUCI observation, we identify at least eight galaxy members in this structure with spectroscopic redshift z = 1 .687 1 .699, including the FRII galaxy at z = 1.699. Most members are distributed within 400 kpc from the FRII core. Nonetheless, the whole structure is likely much more extended, as one of the members was serendipitously found at similar to 800 kpc projected separation. The classic radio structure of the FRII itself extends for similar to 600 kpc across the sky. Most of the identified overdensity members are blue, compact galaxies that are actively forming stars at rates of similar to 8-60 M-circle dot yr(-1). For the brightest of them, a half-light radius of 2 .2 similar to 0 .8 kpc at 8000A rest-frame was determined based on adaptive optics-assisted observations with LBT/SOUL in the Ks band. We do not observe any strong galaxy morphological segregation or concentration around the FRII core. This suggests that the structure is far from being virialized and likely constitutes the progenitor of a local massive galaxy group or cluster caught in its main assembly phase. Based on a 500 ks Chandra ACIS-I observation, we found that the FRII nucleus hosts a luminous QSO (L2-10 keV = 1 .3 similar to 10(44) erg s(-1), intrinsic and rest-frame) that is obscured by Compton-thick absorption (N-H = 1.5 +/- 0 .6 x 10(24) cm(-2)). Under standard bolometric corrections, the total measured radiative power (L-rad similar to 4 x 10(45) erg s(-1)) is similar to the jet kinetic power that we estimated from radio observations at 150MHz (P-kin = 6.3 x 10(45) erg s(-1)), in agreement with what is observed in powerful jetted AGN. Our Chandra observation is the deepest so far for a distant FRII within a galaxy overdensity. It revealed significant di ffuse X-ray emission within the region that is covered by the overdensity. In particular, X-ray emission extending for similar to 240 kpc is found around the eastern lobe of the FRII. Four out of the six MUSE star-forming galaxies in the overdensity are distributed in an arc-like shape at the edge of this di ffuse X-ray emission. These objects are concentrated within 200 kpc in the plane of the sky and within 450 kpc in radial separation. Three of them are even more concentrated and fall within 60 kpc in both transverse and radial distance. The probability of observing four out of the six z = 1.7 sources by chance at the edge of the di ffuse emission is negligible. In addition, these four galaxies have the highest specific star formation rates of the MUSE galaxies in the overdensity and lie above the main sequence of field galaxies of equal stellar mass at z = 1.7. We propose that the di ffuse X-rays originate from an expanding bubble of gas that is shock heated by the FRII jet, and that star formation is promoted by the compression of the cold interstellar medium of the galaxies around the bubble, which may be remarkable evidence of positive AGN feedback on cosmological scales.
Galaxy-scale ionised winds driven by ultra-fast outflows in two nearby quasars
(2020) Marasco, A.; Cresci, G.; Nardini, E.; Mannucci, F.; Marconi, A.; Tozzi, P.; Tozzi, G.; Amiri, A.; Venturi, G.; Piconcelli, E.; Lanzuisi, G.; Tombesi, F.; Mingozzi, M.; Perna, M.; Carniani, S.; Brusa, M.; Alighieri, S. di Serego
We used MUSE adaptive optics data in narrow field mode to study the properties of the ionised gas in MR 2251-178 and PG 1126-041, two nearby (z similar or equal to 0.06) bright quasars (QSOs) hosting sub-pc scale ultra-fast outflows (UFOs) detected in the X-ray band. We decomposed the optical emission from diffuse gas into a low- and a high-velocity components. The former is characterised by a clean, regular velocity field and a low (similar to 80 km s(-1)) velocity dispersion. It traces regularly rotating gas in PG 1126-041, while in MR 2251-178 it is possibly associated with tidal debris from a recent merger or flyby. The other component is found to be extended up to a few kpc from the nuclei, and shows a high (similar to 800 km s(-1)) velocity dispersion and a blue-shifted mean velocity, as is expected from outflows driven by active galactic nuclei (AGN). We estimate mass outflow rates up to a few M-circle dot yr(-1) and kinetic efficiencies L-KIN/L-BOL between 1-4x10(-4), in line with those of galaxies hosting AGN of similar luminosities. The momentum rates of these ionised outflows are comparable to those measured for the UFOs at sub-pc scales, which is consistent with a momentum-driven wind propagation. Pure energy-driven winds are excluded unless about 100x additional momentum is locked in massive molecular winds. In comparing the outflow properties of our sources with those of a small sample of well-studied QSOs hosting UFOs from the literature, we find that winds seem to systematically lie either in a momentum-driven or an energy-driven regime, indicating that these two theoretical models bracket the physics of AGN-driven winds very well.
Inferring Compton-thick AGN candidates at z > 2 with Chandra using the > 8 keV rest-frame spectral curvature.
(2017) Baronchelli, Linda; Ricci, Claudio; Treister, Ezequiel; Koss, M.; Schawinski, K.; Cardamone, C.; Civano, F.; Comastri, A.; Elvis, M.; Lanzuisi, G.; Marchesi, S.
NuSTAR. reveals the extreme properties of the super-Eddington accreting supermassive black hole in PG. 1247+267
(2016) Lanzuisi, G.; Perna, M.; Comastri, A.; Cappi, M.; Dadina, M.; Marinucci, A.; Masini, A.; Matt, G.; Vagnetti, F.; Bauer, Franz Erik; Vignali, C.; Ballantyne, D.; Boggs, S.; Brandt, W.; Brusa, M.; Craig, W.; Ricci, Claudio
The Chandra COSMOS Legacy survey: optical/IR identifications
(2016) Marchesi, Stefano; Treister, Ezequiel; Civano, Francesca; Elvis, Martin; Salvato, M.; Brusa, Marcella; Comastri, A.; Gilli, R.; Hasinger, G.; Lanzuisi, G.; Miyaji, T.; Urry, C. Megan
The Chandra COSMOS-Legacy Survey: Source X-Ray Spectral Properties
(2016) Marchesi, Stefano; Treister, Ezequiel; Lanzuisi, G.; Civano, Francesca; Iwasawa, K.; Suh, H.; Comastri, A.; Zamorani, G.; Allevato, Viola; Griffiths, R.; Miyaji, T.
The Chandra COSMOS-Legacy Survey: The z>3 Sample
(2016) Marchesi, Stefano; Treister, Ezequiel; Civano, Francesca; Salvato, M.; Shankar, F.; Comastri, A.; Elvis, Martin; Lanzuisi, G.; Trakhtenbrot, Benny; Vignali, C.; Zamorani, G.; Allevato, Viola
The deep Chandra survey in the SDSS J1030+0524 field
(2020) Nanni, R.; Gilli, R.; Vignali, C.; Mignoli, M.; Peca, A.; Marchesi, S.; Annunziatella, M.; Brusa, M.; Calura, F.; Cappelluti, N.; Chiaberge, M.; Comastri, A.; Iwasawa, K.; Lanzuisi, G.; Liuzzo, E.; Marchesini, D.; Prandoni, I.; Tozzi, P.; Vito, F.; Zamorani, G.; Norman, C.
We present the X-ray source catalog for the similar to 479 ks Chandra exposure of the SDSS J1030+0524 field, which is centered on a region that shows the best evidence to date of an overdensity around a z > 6 quasar, and also includes a galaxy overdensity around a Compton-thick Fanaroff-Riley type II (FRII) radio galaxy at z = 1.7. Using wavdetect for initial source detection and ACIS Extract for source photometry and significance assessment, we create preliminary catalogs of sources that are detected in the full (0.5-7.0 keV), soft (0.5-2.0 keV), and hard (2-7 keV) bands, respectively. We produce X-ray simulations that mirror our Chandra observation to filter our preliminary catalogs and achieve a completeness level of > 91% and a reliability level of similar to 95% in each band. The catalogs in the three bands are then matched into a final main catalog of 256 unique sources. Among them, 244, 193, and 208 are detected in the full, soft, and hard bands, respectively. The Chandra observation covers a total area of 335 arcmin(2) and reaches flux limits over the central few square arcmins of similar to 3 x 10(-16), 6 x 10(-17), and 2 x 10(-16) erg cm(-2) s(-1) in the full, soft, and hard bands, respectively This makes J1030 field the fifth deepest extragalactic X-ray survey to date. The field is part of the Multiwavelength Survey by Yale-Chile (MUSYC), and is also covered by optical imaging data from the Large Binocular Camera (LBC) at the Large Binocular Telescope (LBT), near-infrared imaging data from the Canada France Hawaii Telescope WIRCam (CFHT/WIRCam), and Spitzer IRAC. Thanks to its dense multi-wavelength coverage, J1030 represents a legacy field for the study of large-scale structures around distant accreting supermassive black holes. Using a likelihood ratio analysis, we associate multi-band (r, z, J, and 4.5 mu m) counterparts for 252 (98.4%) of the 256 Chandra sources, with an estimated reliability of 95%. Finally, we compute the cumulative number of sources in each X-ray band, finding that they are in general agreement with the results from the Chandra Deep Fields.
The MUSE view of He 2-10: No AGN ionization but a sparkling starburst
(2017) Cresci, G.; Vanzi, Leonardo; Telles, E.; Lanzuisi, G.; Brusa, M.; Mingozzi, M.; Sauvage, M.; Johnson, K.
The NuSTAR Extragalactic Surveys: X-Ray Spectroscopic Analysis of the Bright Hard-band Selected Sample
(2018) Zappacosta, L.; Ricci, Claudio; Treister, Ezequiel; Comastri, A.; Civano, Francesca; Puccetti, S.; Fiore, F.; Aird, J. A.; Del Moro, A.; Lansbury, George B.; Lanzuisi, G.
The universal shape of the X-ray variability power spectrum of AGN up to z ∼ 3
(2023) Paolillo, M.; Papadakis, I. E.; Brandt, W. N.; Bauer, F. E.; Lanzuisi, G.; Allevato, V.; Shemmer, O.; Zheng, X. C.; De Cicco, D.; Gilli, R.; Luo, B.; Thomas, M.; Tozzi, P.; Vito, F.; Xue, Y. Q.
Aims. We study the ensemble X-ray variability properties of active galactic nuclei (AGN) over large ranges of timescale (20 ks <= T <= 14 yr), redshift (0 <= z less than or similar to 3), luminosity (10(40) erg s(-1) <= L-X <= 10(46) erg s(-1)), and black hole (BH) mass (10(6) <= M-circle dot <= 10(9)).
The XMM deep survey in the CDF-S IX. An X-ray outflow in a luminous obscured quasar at z ≈ 1.6
(2015) Vignali, C.; Iwasawa, K.; Comastri, A.; Gilli, R.; Lanzuisi, G.; Ranalli, P.; Cappelluti, N.; Mainieri, V.; Georgantopoulos, I.; Bauer, Franz Erik; Fritz, J.; Brusa, M.; Brandt, W.; Carrera, F.; Fiore, F.; Tombesi, F.

Browsing by Author "Lanzuisi, G."

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