Alessandra De Rosa
A5032322585- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Mechanics and Biomechanics Studies
- Radio Astronomy Observations and Technology
- High-pressure geophysics and materials
- Particle Accelerators and Free-Electron Lasers
- Particle Detector Development and Performance
- Stellar, planetary, and galactic studies
- Solar and Space Plasma Dynamics
- Adaptive optics and wavefront sensing
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Neutrino Physics Research
- Scientific Measurement and Uncertainty Evaluation
- Nuclear Physics and Applications
- Particle accelerators and beam dynamics
- Geophysics and Gravity Measurements
- Superconducting Materials and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced X-ray Imaging Techniques
Institute for Space Astrophysics and Planetology
2015-2024
Brera Astronomical Observatory
2024
Fundação Carlos Chagas
2024
National Institute for Astrophysics
2009-2023
Institute of Space Sciences
2018
United States Naval Research Laboratory
2018
Observatoire astronomique de Strasbourg
2016
University of Pisa
2016
Institut de Planétologie et d'Astrophysique de Grenoble
2016
Centre National de la Recherche Scientifique
2016
We present the first catalog of active galactic nuclei (AGNs) detected by Large Area Telescope (LAT), corresponding to 11 months data collected in scientific operation mode. The First LAT AGN Catalog (1LAC) includes 671 γ-ray sources located at high Galactic latitudes (|b|>10°) that are with a test statistic greater than 25 and associated statistically AGNs. Some multiple AGNs, consequently, 709 comprising 300 BL Lacertae objects, 296 flat-spectrum radio quasars, 41 AGNs other types, 72...
Abstract The Laser Interferometer Space Antenna (LISA) will be a transformative experiment for gravitational wave astronomy, and, as such, it offer unique opportunities to address many key astrophysical questions in completely novel way. synergy with ground-based and space-born instruments the electromagnetic domain, by enabling multi-messenger observations, add further discovery potential of LISA. next decade is crucial prepare community LISA’s first observations. This review outlines...
Supermassive black holes in the nuclei of active galaxies expel large amounts matter through powerful winds ionized gas. The archetypal galaxy NGC 5548 has been studied for decades, and high-resolution X-ray UV observations have previously shown a persistent outflow. An observing campaign 2013 with six space observatories shows nucleus to be obscured by long-lasting, clumpy stream gas never seen before. It blocks 90% soft emission causes simultaneous deep, broad absorption troughs. outflow...
A black hole x-ray binary (XRB) system forms when gas is stripped from a normal star and accretes onto hole, which heats the sufficiently to emit x-rays. We report polarimetric observation of XRB Cygnus X-1 using Imaging Polarimetry Explorer. The electric field position angle aligns with outflowing jet, indicating that jet launched inner emitting region. polarization degree (4.01+-0.20)% at 2 8 kiloelectronvolts, implying accretion disk viewed closer edge-on than orbit. observations reveal...
Abstract Most of the light from blazars, active galactic nuclei with jets magnetized plasma that point nearly along line sight, is produced by high-energy particles, up to around 1 TeV. Although are known be ultimately powered a supermassive black hole, how particles accelerated such high energies has been an unanswered question. The process must related magnetic field, which can probed observations polarization jets. Measurements radio optical polarization—the only range available until...
ABSTRACT We present an X-ray spectropolarimetric analysis of the bright Seyfert galaxy NGC 4151. The source has been observed with Imaging Polarimetry Explorer (IXPE) for 700 ks, complemented simultaneous XMM–Newton (50 ks) and NuSTAR (100 pointings. A polarization degree Π = 4.9 ± 1.1 per cent angle Ψ 86° 7° east north (68 confidence level) are measured in 2–8 keV energy range. shows that could be entirely due to reflection. Given low reflection flux IXPE band, this requires, however, a...
Abstract We report on an observational campaign the bright black hole (BH) X-ray binary Swift J1727.8–1613 centered around five observations by Imaging Polarimetry Explorer. These track for first time evolution of polarization a BH across hard to soft state transition. The 2–8 keV degree decreased from ∼4% ∼3% observations, but angle remained oriented in north–south direction throughout. Based with Australia Telescope Compact Array, we find that intrinsic 7.25 GHz radio aligns polarization....
Abstract The Lunar Gravitational-wave Antenna (LGWA) is a proposed array of next-generation inertial sensors to monitor the response Moon gravitational waves (GWs). Given size and expected noise produced by lunar seismic background, LGWA would be able observe GWs from about 1 mHz Hz. This make missing link between space-borne detectors like LISA with peak sensitivities around few millihertz future terrestrial Einstein Telescope or Cosmic Explorer. In this article, we provide first...
We present the first results from a 325-ks observation of Seyfert 1 galaxy MCG–6-30-15 with XMM-Newton and BeppoSAX. The strong, broad, skewed iron line is clearly detected well characterized by steep emissivity profile within 6rg (i.e. 6GM/c2) flatter beyond. inner radius emission appears to lie at about 2rg, consistent reported both an earlier Wilms et al. part ASCA Iwasawa when source was in lower flux state. do depend however on assumed incident power-law continuum lack complex...
The X-ray spectra of many active galactic nuclei (AGNs) show a soft excess below 1–2 keV on top the extrapolated high-energy power law. origin this component is uncertain. It could be signature relativistically blurred, ionized reflection or tail thermal Comptonization in warm ( kT ~ 1 keV), optically thick τ ≃ 10–20) corona producing optical/UV to emission. purpose present paper test model statistically significant sample unabsorbed, radio-quiet AGNs with XMM-Newton archival data, providing...
An extensive multi-satellite campaign on NGC 5548 has revealed this archetypal Seyfert-1 galaxy to be in an exceptional state of persistent heavy absorption. Our observations taken 2013-2014 with XMM-Newton, Swift, NuSTAR, INTEGRAL, Chandra, HST and two ground-based observatories have together enabled us establish that unexpected phenomenon is caused by outflowing stream weakly ionised gas (called the obscurer), extending from vicinity accretion disk broad-line region. In work we present...
eXTP is a science mission designed to study the state of matter under extreme conditions density, gravity and magnetism. Primary goals are determination equation at supra-nuclear measurement QED effects in highly magnetized star, accretion strong-field regime gravity. targets include isolated binary neutron stars, strong magnetic field systems like magnetars, stellar-mass supermassive black holes. The carries unique unprecedented suite state-of-the-art scientific instruments enabling for...
A soft X-ray excess above the 2-10 keV power law extrapolation is generally observed in AGN spectra. Presently there are two competitive models to explain it: blurred ionized reflection and warm Comptonisation. In latter case, observations suggest a corona temperature $\sim$ 1 optical depth 10. Moreover, radiative constraints from spectral fits with Comptonisation that most of accretion should be released corona. The disk below basically non-dissipative, radiating only reprocessed emission...
THESEUS, one of the two space mission concepts being studied by ESA as candidates for next M5 within its Comsic Vision programme, aims at fully exploiting Gamma-Ray Bursts (GRB) to solve key questions about early Universe, well becoming a cornerstone multi-messenger and time-domain astrophysics. By investigating first billion years Universe through high-redshift GRBs, THESEUS will shed light on main open issues in modern cosmology, such population primordial low mass luminosity galaxies,...
Abstract Particle acceleration mechanisms in supermassive black hole jets, such as shock acceleration, magnetic reconnection, and turbulence, are expected to have observable signatures the multiwavelength polarization properties of blazars. The recent launch Imaging X-Ray Polarimetry Explorer (IXPE) enables us, for first time, use X-ray band (2–8 keV) probe jet synchrotron emission high-synchrotron-peaked BL Lac objects (HSPs). We report discovery linear (degree Π x = 15% ± 2% electric...
We report on the first detection of linearly polarized x-ray emission from an ultra-magnetized neutron star with Imaging X-ray Polarimetry Explorer (IXPE). The IXPE 35 observations anomalous pulsar 4U 0142+61 reveal a linear polarization degree $(12\pm 1)\%$ throughout 2--8 keV band. detect substantial variation energy: is $(14\pm at 2--4 and $(41\pm 7)\%$ 5.5--8 keV, while it drops below instrumental sensitivity around 4--5 where angle swings by $\sim 90^\circ$. give us completely new...
We report on the first observation of a radio-quiet Active Galactic Nucleus (AGN) using polarized X-rays: Seyfert 1.9 galaxy MCG-05-23-16. This source was pointed with Imaging X-ray Polarimetry Explorer (IXPE) starting May 14, 2022 for net observing time 486 ks, simultaneously XMM-Newton (58 ks) and NuSTAR (83 ks). A polarization degree smaller than $\Pi<4.7\%$ (at 99% c.l.) is derived in 2-8 keV energy range, where emission dominated by primary component ascribed to hot corona. The...