A. De Luca
A5065755325- Pulsars and Gravitational Waves Research
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- High-pressure geophysics and materials
- Astronomical Observations and Instrumentation
- Stellar, planetary, and galactic studies
- Geophysics and Gravity Measurements
- Geophysics and Sensor Technology
- Particle Detector Development and Performance
- Astronomy and Astrophysical Research
- Particle Accelerators and Free-Electron Lasers
- Radio Astronomy Observations and Technology
- Dark Matter and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Astro and Planetary Science
- Superconducting Materials and Applications
- Advanced X-ray Imaging Techniques
- SAS software applications and methods
- Mechanics and Biomechanics Studies
- Cosmology and Gravitation Theories
- Solar and Space Plasma Dynamics
- Atmospheric Ozone and Climate
Laboratoire de Physique Théorique
2023-2024
CY Cergy Paris Université
2023-2024
Laboratoire de Physique Théorique et Modélisation
2024
Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano
2014-2024
Centre National de la Recherche Scientifique
1998-2023
National Institute for Astrophysics
2013-2023
Istituto Nazionale di Fisica Nucleare, Sezione di Pavia
2013-2022
Istituto Nazionale di Fisica Nucleare
2012-2019
Istituto Universitario di Studi Superiori di Pavia
2008-2018
Institut d'Astrophysique Spatiale
1994-2018
ABSTRACT We present a catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), primary science instrument on Fermi Gamma-ray Space (Fermi) , during first 11 months phase mission, which began 2008 August 4. The First -LAT (1FGL) contains 1451 and characterized in 100 MeV to GeV range. Source detection was based average flux over month period, threshold likelihood Test Statistic is 25, corresponding significance just 4σ. 1FGL includes source location regions,...
We present the second catalog of high-energy gamma-ray sources detected by Large Area Telescope (LAT), primary science instrument on Fermi Gamma-ray Space (Fermi), derived from data taken during first 24 months phase mission, which began 2008 August 4. Source detection is based average flux over 24-month period. The Second Fermi-LAT (2FGL) includes source location regions, defined in terms elliptical fits to 95% confidence regions and spectral power-law, exponentially cutoff or log-normal...
This catalog summarizes 117 high-confidence ⩾0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on Fermi satellite. Half are neutron stars discovered LAT through periodicity searches in and radio around unassociated source positions. The pulsars evenly divided into groups: millisecond pulsars, young radio-loud radio-quiet pulsars. We characterize pulse profiles energy spectra derive luminosities when distance information exists. Spectral...
The dramatic increase in the number of known gamma-ray pulsars since launch Fermi Gamma-ray Space Telescope (formerly GLAST) offers first opportunity to study a sizable population these high-energy objects. This catalog summarizes 46 high-confidence pulsed detections using six months data taken by Large Area (LAT), Fermi's main instrument. Sixteen previously unknown were discovered searching for signals at positions bright sources seen with LAT, or objects suspected be neutron stars based on...
ABSTRACT Following its launch in 2008 June, the Fermi Gamma-ray Space Telescope ( ) began a sky survey August. The Large Area (LAT) on three months produced deeper and better resolved map of γ-ray than any previous space mission. We present here initial results for energies above 100 MeV 205 most significant (statistical significance greater ∼10σ) sources these data. These are best characterized localized point-like (i.e., spatially unresolved) early mission
Spinning up an extragalactic neutron star Ultraluminous x-ray sources (ULXs) are strange objects in other galaxies that cannot be explained by conventional accretion onto stellar-mass objects. This has led to exotic interpretations, such as the long-sought intermediate-mass black holes. Israel et al. observed a ULX nearby galaxy NGC 5907 and found it is instead star. The spinning accreting material so fast its spin period quickly accelerating. only way can consume enough explain these...
A young and energetic pulsar powers the well-known Crab Nebula. Here, we describe two separate gamma-ray (photon energy greater than 100 mega-electron volts) flares from this source detected by Large Area Telescope on board Fermi Gamma-ray Space Telescope. The first flare occurred in February 2009 lasted approximately 16 days. second was September 2010 4 During these outbursts, flux nebula increased factors of four six, respectively. brevity implies that gamma rays were emitted via...
The well known Crab Nebula is at the center of SN1054 supernova remnant. It consists a rotationally-powered pulsar interacting with surrounding nebula through relativistic particle wind. emissions originating from and have been considered to be essentially stable. Here we report detection strong gamma-ray (100 MeV-10 GeV) flares observed by AGILE satellite in September, 2010 October, 2007. In both cases, unpulsed flux increased factor 3 compared non-flaring flux. flare luminosity short...
Pulsars are rapidly-rotating, highly-magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there more than 1800 known radio pulsars, until recently, only seven were observed to pulse in gamma rays and these all discovered at other wavelengths. The Fermi Large Area Telescope makes it possible pinpoint through their gamma-ray pulsations. We report detection of 16 pulsars blind frequency searches using LAT. Most coincident with previously unidentified...
NGC 7793 P13 is a variable (luminosity range ~100) ultraluminous X-ray source (ULX) proposed to host stellar-mass black hole of less than 15 M$_{\odot}$ in binary system with orbital period 64 d and 18-23 B9Ia companion. Within the EXTraS project we discovered pulsations at ~0.42 s two XMM-Newton observations P13, during which was detected $L_{\mathrm{X}}\sim2.1\times10^{39}$ $5\times10^{39}$ erg s$^{-1}$ (0.3-10 keV band). These findings unambiguously demonstrate that compact object neutron...
Abstract We discovered 2.8 s pulsations in the X-ray emission of ultraluminous source (ULX) M51 ULX-7 within UNSEeN project, which was designed to hunt for new pulsating ULXs (PULXs) with XMM-Newton. The pulse shape is sinusoidal, and large variations its amplitude were observed even single exposures (pulsed fraction from less than 5% 20%). Source variable, generally at an luminosity between 10 39 40 erg −1 , located outskirts spiral galaxy M51a a distance 8.6 Mpc. According our analysis,...
We have measured the spectrum of Cosmic X-ray Background (CXB) in 2-8 keV range with high throughput EPIC/MOS instrument onboard XMM-Newton. A large sample galactic latitude observations was used, covering a total solid angle 5.5 square degrees. Our study is based on very careful characterization and subtraction instrumental background, which crucial for robust measurement faintest diffuse source sky. The CXB consistent power law having photon index Gamma=1.41+/-0.06 normalization...
We discuss the methods used to compile a high signal-to-noise dataset representative of both instrumental and cosmic background signal measured at galactic latitude by XMM-Newton EPIC cameras. The characteristics are described potential applications derived in general science analysis outlined. In case X-ray background, transition between hard power-law spectrum (due integrated emission unresolved, largely extragalactic, point sources) softer thermal (produced hot plasma associated with...
We report on gamma-ray observations of the Crab Pulsar and Nebula using 8 months survey data with Fermi Large Area Telescope (LAT). The high quality light curve obtained ephemeris provided by Nancay Jodrell Bank radio telescopes shows two main peaks stable in phase energy. first peak leads pulse (281 \pm 12 21) mus, giving new constraints production site non-thermal emission pulsar magnetospheres. improved sensitivity unprecedented statistics afforded LAT enable precise measurement spectral...
Gamma-Ray Pulsar Bonanza Most of the pulsars we know about were detected through their radio emission; a few are known to pulse gamma rays but first at other wavelengths (see Perspective by Halpern ). Using Fermi Space Telescope, Abdo et al. (p. 840 , published online 2 July; see cover) report detection 16 previously unknown based on gamma-ray emission alone. Thirteen these coincide with unidentified sources, solving 30-year-old mystery identities. Pulsars fast-rotating neutron stars. With...
We report the discovery of eight gamma-ray pulsars in blind frequency searches using LAT, onboard Fermi Gamma-ray Space Telescope. Five are young (tau_c<100 kyr), energetic (Edot>10^36 erg/s), and located within Galactic plane (|b|<3 deg). The remaining three older, less energetic, off plane. associated with sources included LAT bright source list, but only one, PSR J1413-6205, is clearly an EGRET source. J1023-5746 has smallest characteristic age (tau_c=4.6 kyr) most (Edot=1.1E37 erg/s) all...
This Letter presents the first results from observations of LSI +61 303 using Large Area Telescope data Fermi Gamma-Ray Space between 2008 August and 2009 March. Our indicate variability that is consistent with binary period, emission being modulated at 26.6 +/- 0.5 days. constitutes detection orbital periodicity in high-energy gamma rays (20 MeV-100 GeV, HE). The light curve characterized by a broad peak after periastron, as well smaller just before apastron. spectrum best represented power...
The Fermi Large Area Telescope First Source Catalog (1FGL) provided spatial, spectral, and temporal properties for a large number of gamma-ray sources using uniform analysis method. After correlating with the most-complete catalogs source types known to emit gamma rays, 630 these are "unassociated" (i.e. have no obvious counterparts at other wavelengths). Here, we employ two statistical analyses primary characteristics unassociated in an effort correlate their AGN pulsar populations 1FGL....
ABSTRACT The 6.67 hr periodicity and the variable X-ray flux of central compact object (CCO) at center supernova remnant RCW 103, named 1E 161348–5055, have been always difficult to interpret within standard scenarios an isolated neutron star (NS) or a binary system. On 2016 June 22, Burst Alert Telescope (BAT) on board Swift detected magnetar-like short burst from direction also coincident with large long-term outburst. Here, we report Chandra , Nuclear Spectroscopic Array (BAT XRT)...
We investigate the crucial role played by a global symmetry in purification timescales and phase transitions of monitored free fermionic systems separating mixed pure phase. Concretely, we study Majorana Dirac circuits with $\mathbb{Z}_2$ U(1) symmetries, respectively. In first case, demonstrate $L$ sites has timescale that scales as $\tau_P\sim L \ln $. At $1\ll t\ll \tau_P$ system attains finite residual entropy, use to unveil critical properties transition. contrast, fermions manifest...
XMM-Newton EPIC observations of PSR B0656+14, B1055-52, and Geminga have substantially increased the collection statistics available for these three isolated neutron stars, so apparently similar to deserve nickname Three Musketeers, given them by Becker & Trümper. Here we take advantage perform phase-resolved spectroscopy all objects. The phase-averaged spectrum Musketeers is best described a three-component model. This includes two blackbody components—a cooler one, possibly originating...
Observations with the Newton X-ray Multimirror Mission satellite show a strong periodic modulation at 6.67 +/- 0.03 hours of x-ray source center 2000-year-old supernova remnant RCW 103. No fast pulsations are visible. If genetically tied to remnant, could either be an binary, composed compact object and low-mass star in eccentric orbit, or isolated neutron star. In latter case, combination its age period would indicate that it is peculiar magnetar, dramatically slowed down, possibly by...
We report on analysis of timing and spectroscopy the Vela pulsar using 11 months observations with Large Area Telescope (LAT) Fermi Gamma-ray Space Telescope.The intrinsic brightness at GeV energies combined angular resolution sensitivity LAT allows us to make most detailed study date energy-dependent light curves phase-resolved spectra, a LAT-derived model.The curve consists two peaks (P1 P2) connected by bridge emission containing third peak (P3).We have confirmed strong decrease P1/P2...
We report the discovery of nine previously unknown gamma-ray pulsars in a blind search data from Fermi Large Area Telescope (LAT). The were found with novel hierarchical method originally developed for detecting continuous gravitational waves rapidly rotating neutron stars. Designed to find isolated spinning at up kHz frequencies, new is computationally efficient and incorporates several advances, including metric-based gridding parameter space (frequency, frequency derivative, sky location)...