A5032342022- Astrophysical Phenomena and Observations
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Trace Elements in Health
- Mitochondrial Function and Pathology
- Gamma-ray bursts and supernovae
- Iron Metabolism and Disorders
- Metabolism and Genetic Disorders
- Heme Oxygenase-1 and Carbon Monoxide
- Porphyrin Metabolism and Disorders
- Biochemical effects in animals
- Cassava research and cyanide
- Alcohol Consumption and Health Effects
- Drug Transport and Resistance Mechanisms
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Drug-Induced Hepatotoxicity and Protection
- Hemoglobin structure and function
- Aldose Reductase and Taurine
- Adipose Tissue and Metabolism
- Pancreatic function and diabetes
- Eicosanoids and Hypertension Pharmacology
- Neuroscience and Neuropharmacology Research
- Sulfur Compounds in Biology
- Adaptive optics and wavefront sensing
Scuola Internazionale Superiore di Studi Avanzati
2020-2023
Osservatorio di Astrofisica e Scienza dello Spazio
2018-2023
Dartmouth College
2018-2020
Osservatorio astronomico di Bologna
2016-2018
University of Bologna
2016-2018
Center for Astrophysics Harvard & Smithsonian
2018
University of Modena and Reggio Emilia
1990-2005
University of Genoa
1997
University of Siena
1995
IRCCS Istituto Auxologico Italiano
1995
Aims. We study the connection between masing disk and obscuring torus in Seyfert 2 galaxies.
Broadband X-ray spectroscopy of the emission produced in coronae active galactic nuclei (AGN) can provide important insights into physical conditions very close to their central supermassive black holes. The temperature Comptonizing plasma that forms corona is manifested through a high-energy cutoff has been difficult directly constrain even brightest AGN because it requires high-quality data at energies above 10 keV. In this paper we present large collection coronal constraints for obscured...
We have discovered heavy obscuration in the dual active galactic nucleus (AGN) Swift/Burst Alert Telescope (BAT) source SWIFT J2028.5+2543 using Nuclear Spectroscopic Array (NuSTAR). While an early XMM-Newton study suggested emission was mainly from NGC 6921, superior spatial resolution of NuSTAR above 10 keV resolves Swift/BAT into two sources associated with nearby galaxies MCG +04-48-002 and 6921 (z = 0.014) a projected separation 25.3 kpc (91"). NuSTAR's sensitivity finds both are...
We identify sources with extremely hard X-ray spectra (i.e., photon indices of Gamma<0.6 in the 13 sq. deg. NuSTAR serendipitous survey, to search for most highly obscured AGNs detected at >10 keV. Eight extreme are identified, and we use data combination lower energy observations (from Chandra, Swift XRT, XMM-Newton) characterize broad-band (0.5-24 keV) spectra. find that all AGNs, including three robust Compton-thick (CT; N_H > 1.5e24 cm^-2) low redshift (z<0.1), a likely-CT AGN higher...
We present a new, ambitious survey performed with the Chandra X-ray Observatory of 9.3 deg2 Boötes field NOAO Deep Wide-Field Survey. The wide probes statistically representative volume universe at high redshift. Wide-field Survey exploits excellent sensitivity and angular resolution over area, combining 281 observations spanning 15 yr, for total exposure time 3.4 Ms, detects 6891 point sources down to limiting fluxes 4.7 × 10−16, 1.5 9 ×10−16 erg cm−2 s−1 in 0.5–7, 0.5–2, 2–7 keV bands,...
We discuss the spectral analysis of a sample 63 Active Galactic Nuclei (AGN) detected above limiting flux $S(8-24$ keV$)=7\times10^{-14}$ erg/s/cm$^2$ in multi-tiered NuSTAR Extragalactic Survey program. The sources span redshift range z=0-2.1 (median $\langle$z$\rangle=$0.58). is performed over broad 0.5-24 keV energy range, combining with Chandra and/or XMM-Newton data and employing empirical physically motivated models. This constitutes largest AGN selected at $ >10$ to be homogeneously...
We present $NuSTAR$ X-ray observations of the active galactic nucleus (AGN) in NGC 7674. The source shows a flat spectrum, suggesting that it is obscured by Compton-thick gas columns. Based upon long-term flux dimming, previous work suggested alternate possibility recently switched-off AGN with observed X-rays being lagged echo from torus. Our high-quality data show to be reflection-dominated hard X-rays, but relatively weak neutral Fe K$\alpha$ emission line (equivalent width [EW] $\approx$...
We present X-ray bolometric correction factors, $\kappa_{Bol}$ ($\equiv L_{Bol}/L_X$), for Compton-thick (CT) active galactic nuclei (AGN) with the aim of testing AGN torus models, probing orientation effects, and estimating output most obscured AGN. adopt luminosities, $L_{Bol}$, from literature infrared (IR) modeling compile published intrinsic 2--10 keV $L_{X}$, NuSTAR data. Our sample consists 10 local CT where both these estimates are available. test systematic differences in values...
PG1247+267 is one of the most luminous known quasars at $z\sim2$ and a strongly super-Eddington accreting SMBH candidate. We obtained NuSTAR data this intriguing source in December 2014 with aim studying its high-energy emission, leveraging broad band covered by new archival XMM-Newton data. Several measurements are agreement scenario for PG1247+267: soft power law ($Γ=2.3\pm0.1$); weak ionized Fe emission line hint presence outflowing gas surrounding SMBH. The an extreme reflection...
We analyse high-quality NuSTAR observations of the local (z = 0.011) Seyfert 2 active galactic nucleus (AGN) IC 3639, in conjunction with archival Suzaku and Chandra data. This provides first broadband X-ray spectral analysis source, spanning nearly two decades energy (0.5-30 keV). Previous source below 10 keV indicated strong reflection/obscuration on basis a pronounced iron fluorescence line at 6.4 keV. The hard coverage NuSTAR, together self-consistent toroidal reprocessing models,...
Abstract We present new estimates on the fraction of heavily X-ray-obscured, Compton-thick (CT) active galactic nuclei (AGNs) out to a redshift z ≤ 0.8. From sample 540 AGNs selected by mid-infrared (MIR) properties in observed X-ray survey fields, we forward model observed-to-intrinsic luminosity ratio ( <?CDATA ${R}_{{L}_{{\rm{X}}}}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mi>L</mml:mi> <mml:mi...
Due to their heavily obscured central engines, the growth rate of Compton-thick (CT) active galactic nuclei (AGN) is difficult measure. A statistically significant correlation between Eddington ratio, λ$_{Edd}$, and X-ray power-law index, Γ, observed in unobscured AGN offers an estimate from spectroscopy (albeit with large scatter). However, since X-rays undergo reprocessing by Compton scattering photoelectric absorption when line-of-sight engine obscured, recovery intrinsic Γ challenging....
We present a large sample of infrared-luminous candidate active galactic nuclei (AGNs) that lack X-ray detections in Chandra, XMM-Newton, and NuSTAR fields. selected all optically detected SDSS sources with redshift measurements, combined additional broadband photometry from WISE, UKIDSS, 2MASS, GALEX, modeled the spectral energy distributions (SEDs) our sources. parameterize nuclear obscuration SEDs $E(B\!-\!V)_{\text{AGN}}$ uncover thousands powerful obscured AGNs counterparts, many which...
It has been found that oligomycin inhibits up to at least 50% state‐4 mitochondrial respiration. A time dependence of inhibition shown. titration curve for respiration sigmoidal profile presented. The possibility misreading this effect, so far never reported, excluded by evaluating the quality preparations used in respect their morphological, functional and electrochemical properties. conclusion therefore put forward most part steady‐state‐4 is driven ATP synthesis.
We present $NuSTAR$ observations of four active galactic nuclei (AGN) located within 15 Mpc. These AGN, namely ESO 121-G6, NGC 660, 3486 and 5195, have observed X-ray luminosities $L_{\rm 2-10\ keV, obs} \lesssim$ 10$^{39}$ erg s$^{-1}$, classifying them as low luminosity AGN (LLAGN). perform broadband spectral analysis for the by combining our data with $Chandra$ or $XMM-Newton$ to directly measure their column densities ($N_{\rm H}$) infer intrinsic power. complement archival new high...