D. Paneque
A5050812987- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Particle Detector Development and Performance
- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Particle Accelerators and Free-Electron Lasers
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Galaxies: Formation, Evolution, Phenomena
- High-Energy Particle Collisions Research
- Radiation Detection and Scintillator Technologies
- Geophysics and Gravity Measurements
- Quantum Chromodynamics and Particle Interactions
- Gyrotron and Vacuum Electronics Research
- Stellar, planetary, and galactic studies
- Photocathodes and Microchannel Plates
- Nuclear Physics and Applications
- Astro and Planetary Science
- Calibration and Measurement Techniques
Institut d'Estudis Espacials de Catalunya
2024
Max Planck Institute for Physics
2015-2024
Universitat de Barcelona
2021-2024
Centro Brasileiro de Pesquisas Físicas
2017-2024
Institut de Recherche sur les Lois Fondamentales de l'Univers
2023
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2023
ETH Zurich
2017-2023
École Polytechnique
2023
Istituto Nazionale di Fisica Nucleare, Sezione di Padova
2003-2023
Deutsches Elektronen-Synchrotron DESY
2023
The blazar Mrk 501 was observed at energies above 0.10 TeV with the MAGIC Telescope from 2005 May through July. high sensitivity of instrument enabled determination flux and spectrum source on a night-by-night basis. Throughout our observational campaign, found to vary by an order magnitude. Intranight variability flux-doubling times down 2 minutes during two most active nights, namely, June 30 July 9. These are fastest variations ever in 501. ~20 minute long flare 9 showed indication 4 ± 1...
Microquasars are binary star systems with relativistic radio-emitting jets. They potential sources of cosmic rays and can be used to elucidate the physics We report detection variable gamma-ray emission above 100 gigaelectron volts from microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar phase, which suggests that is periodic. The strongest not observed when two stars closest one another, implying strong modulation or absorption processes.
The Fermi Large Area Telescope (LAT) has provided the most detailed view to date of emission towards Galactic centre (GC) in high-energy gamma-rays. This paper describes analysis data taken during first 62 months mission energy range 1-100 GeV from a $15^\circ \times 15^\circ$ region about direction GC, and implications for interstellar emissions produced by cosmic ray (CR) particles interacting with gas radiation fields inner Galaxy point sources detected. Specialised models (IEMs) are...
Very high energy (VHE) γ-ray emission from the flat spectrum radio quasar (FSRQ) PKS 1222+21 (4C 21.35, z = 0.432) was detected with MAGIC Cherenkov telescopes during a short observation (∼0.5 hr) performed on 2010 June 17. The detection coincides high-energy MeV/GeV activity measured by Large Area Telescope (LAT) board Fermi satellite. VHE extends about 70 GeV up to at least 400 and can be well described power-law dN/dE ∝ E−Γ photon index Γ 3.75 ± 0.27stat 0.2syst. averaged integral flux...
Dark matter in the Milky Way may annihilate directly into gamma rays, producing a monoenergetic spectral line. Therefore, detecting such signature would be strong evidence for dark annihilation or decay. We search lines Fermi Large Area Telescope observations of halo energy range 200 MeV to 500 GeV using analysis methods from our most recent line searches. The main improvements relative previous works are use 5.8 years data reprocessed with Pass 8 event-level and additional resulting...
The Fermi bubbles are two large structures in the gamma-ray sky extending to 55° above and below Galactic center. We analyze 50 months of Large Area Telescope data between 100 MeV 500 GeV 10° latitude derive spectrum morphology bubbles. thoroughly explore systematic uncertainties that arise when modeling diffuse emission through separate approaches. is well described by either a log parabola or power law with an exponential cutoff. exclude simple more than 7σ significance. cutoff has index...
We report about very high energy (VHE) γ-ray observations of the Crab Nebula with MAGIC telescope. The flux from nebula was measured between 60 GeV and 9 TeV. spectrum can be described by a curved power law dF/dE = f0(E/300 GeV)[a+blog10(E/300 GeV)] normalization f0 (6.0 ± 0.2stat) × 10−10 cm−2 s−1 TeV−1, − 2.31 0.06stat, b 0.26 0.07stat. peak in spectral distribution is estimated at 77 35 GeV. Within observation time experimental resolution telescope, emission steady pointlike. emission's...
The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova shockwaves, but we know little escape from the shock and evolution through turbulent medium surrounding massive stars. Gamma can probe spreading ambient gas radiation fields. Fermi Large Area Telescope (LAT) has observed star-forming region Cygnus X. 1- 100-gigaelectronvolt images reveal 50-parsec-wide cocoon freshly accelerated that flood cavities carved stellar winds...
The light emitted by stars and accreting compact objects through the history of Universe is encoded in intensity extragalactic background (EBL). Knowledge EBL important to understand nature star formation galaxy evolution, but direct measurements are lim- ited Galactic other foreground emissions. Here we report an absorption feature seen combined spectra a sample gamma-ray blazars out redshift z$\sim$1.6. This caused attenuation gamma rays at optical UV frequencies, allowed us measure flux...
ABSTRACT Most of the celestial γ rays detected by Large Area Telescope (LAT) on board Fermi Gamma-ray Space originate from interstellar medium when energetic cosmic interact with nucleons and photons. Conventional point-source extended-source studies rely modeling this diffuse emission for accurate characterization. Here, we describe development Galactic Interstellar Emission Model (GIEM), which is standard adopted LAT Collaboration publicly available. This model based a linear combination...
Dark matter particle annihilation or decay can produce monochromatic gamma-ray lines and contribute to the diffuse background. Flux upper limits are presented for spectral from 7 200 GeV background 4.8 264 obtained two years of Fermi Large Area Telescope data integrated over most sky. We give cross-section lifetime lower dark models that spectrum, including proposed as explanations PAMELA cosmic-ray data.
On 2015 June 16, Fermi-LAT observed a giant outburst from the flat spectrum radio quasar 3C 279 with peak $>100$ MeV flux of $\sim3.6\times10^{-5}\;{\rm photons}\;{\rm cm}^{-2}\;{\rm s}^{-1}$ averaged over orbital period intervals. It is historically highest $\gamma$-ray source including past EGRET observations, isotropic luminosity reaching $\sim10^{49}\;{\rm erg}\;{\rm s}^{-1}$. During outburst, Fermi spacecraft, which has an 95.4 min, was operated in special pointing mode to optimize...
We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in γ-ray spectrum of NGC 1275, central galaxy Perseus cluster. Using 6 years Fermi Large Area Telescope data, we find no evidence ALPs exclude couplings above 5×10^{-12} GeV^{-1} ALP masses 0.5≲m_{a}≲5 neV at 95% confidence. The limits are competitive with sensitivity planned laboratory experiments, and, together other bounds, strongly constrain possibility that can...
Abstract The Large Area Telescope (LAT) aboard the Fermi spacecraft routinely observes high-energy emission from gamma-ray bursts (GRBs). Here we present second catalog of LAT-detected GRBs, covering first 10 yr operations, 2008 to 2018 August 4. A total 186 GRBs are found; these, 91 show in range 30–100 MeV (17 which seen only this band) and 169 detected above 100 MeV. Most these sources were discovered by other instruments ( /GBM, Swift /BAT, AGILE, INTEGRAL ) or reported Interplanetary...
We present a measurement of the cosmic-ray electron+positron spectrum between 7 GeV and 2 TeV performed with almost seven years data collected Fermi Large Area Telescope. find that is well fit by broken power law break energy at about 50 GeV. Above GeV, described single spectral index $3.07 \pm 0.02 \; (\text{stat+syst}) 0.04 (\text{energy measurement})$. An exponential cutoff lower than 1.8 excluded 95\% CL.
Abstract We present a search for spatial extension in high-latitude ( ) sources recent Fermi point source catalogs. The result is the High-Latitude Extended Sources Catalog, which provides extensions (or upper limits thereof) and likelihood profiles suite of tested morphologies. find 24 extended sources, 19 were not previously characterized as extended. These include that are potentially associated with supernova remnants star-forming regions. also found γ -ray emission vicinity Cen A radio...
We report the detection of a new source very high energy (VHE; Eγ ≥ 100 GeV) γ-ray emission located close to Galactic plane, MAGIC J0616+225, which is spatially coincident with supernova remnant IC 443. The observations were carried out telescope in periods 2005 December-2006 January and 2006 December-2007 January. Here we present results from this source, leading VHE signal statistical significance 5.7 σ 2006/2007 data measured differential flux consistent power law, described as dNγ/(dA dt...
We have performed an analysis of the diffuse gamma-ray emission with Fermi Large Area Telescope in Milky Way Halo region searching for a signal from dark matter annihilation or decay. In absence robust signal, constraints are presented. consider both gamma rays produced directly annihilation/decay and by inverse Compton scattering e+e- annihilation/decay. Conservative limits derived requiring that does not exceed observed emission. A second set more stringent is based on modeling foreground...
Axionlike particles (ALPs) are predicted to couple with photons in the presence of magnetic fields. This effect may lead a significant change observed spectra gamma-ray sources such as active galactic nuclei (AGNs). Here we carry out detailed study that for first time simultaneously considers same framework both photon/axion mixing takes place source and one expected occur intergalactic An efficient always means an attenuation photon flux, whereas medium result decrement and/or enhancement...
Recently, the Galactic center has been reported to be a source of very high energy (VHE) γ-rays by CANGAROO, VERITAS, and HESS experiments. The spectra as measured these experiments show substantial differences. In this Letter we present MAGIC observations center, resulting in detection differential γ-ray flux consistent with steady, hard-slope power law, described dNγ/(dA dt dE) = (2.9 ± 0.6) × 10-12(E/TeV)-2.2±0.2 cm-2 s-1 TeV-1. is centered at (R.A., decl.) (17h45m20s, -29°2'). This...
The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This was obtained using 80 months data re-processed with Pass 8, the newest event-level analysis, which significantly improves acceptance and angular resolution instrument. Most 2FHL at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for first time, source count distribution, dN/dS, extragalactic γ-ray E>50 find that it is...
Supermassive black holes with masses of millions to billions solar are commonly found in the centers galaxies. Astronomers seek image jet formation using radio interferometry, but still suffer from insufficient angular resolution. An alternative method resolve small structures is measure time variability their emission. Here, we report on gamma-ray observations galaxy IC 310 obtained MAGIC telescopes revealing doubling scales faster than 4.8 min. Causality constrains size emission region be...
The Fermi Large Area Telescope (LAT) observed two bright X-class solar flares on 2012 March 7, and detected gamma-rays up to 4 GeV. We both during the impulsive temporally-extended emission phases, with above 100 MeV lasting for approximately 20 hours. Accurate localization of gamma-ray production site(s) coincide active region from which X-ray emissions associated these originated. Our analysis >100 shows a relatively rapid monotonic decrease in flux first hour phase, much slower, almost...
The contribution of unresolved sources to the diffuse gamma-ray background could induce anisotropies in this emission on small angular scales. We analyze power spectrum measured by Fermi LAT at Galactic latitudes |b| > 30 deg four energy bins spanning 1 50 GeV. At multipoles \ell \ge 155, corresponding scales \lesssim 2 deg, above photon noise level is detected >99.99% CL 1-2 GeV, 2-5 and 5-10 GeV bins, >99% 10-50 Within each bin takes approximately same value all suggesting that it...