Feb 28, 2024
XMM-Newton's energetic universe joins forces with the Euclid satellite's vision of the sky. A thousand hours of X-ray observations, over a region 40 times the size of the moon, will complement multi-wavelength studies of the cosmic evolution of galaxy clusters. A decisive association to constrain cosmological scenarios and reveal the nature of dark energy.
Nov 27, 2023
The majority of the 3400 known pulsars are "seen" in radio waves, and are located in the Milky Way. The 340 pulsars seen in gamma-rays all share the common feature of being among the 10-15% most powerful pulsars.
An international team led by French researchers, including those at DAp, publishes on November 28, 2023 in the Astrophysical Journal a compilation of 340 pulsars seen in gamma rays (30 MeV - 30 GeV) with the LAT space telescope on NASA's Fermi satellite.
Prior to Fermi's launch in 2008, only 11 pulsars were known in gamma rays. This new catalog brings together all the characteristics of all known gamma-ray pulsars.
Sep 26, 2023
Fermi-LAT telescope continues systematic γ-ray survey
NASA's Fermi satellite was launched in June 2008, and the Fermi-LAT telescope has been carrying out a systematic γ-ray survey of near-GeV energies covering most of the sky every 3 hours (and the whole sky in no more than a week) since August 2008.
May 11, 2023
On October 9, 2022, at 13:16 and 59.99 seconds, a gamma-ray burst (GRB) dazzled almost all the X-ray and gamma ray detectors available at the time. Since their discovery, multi-wavelength telescopes in space and on the ground have continuously monitored these events. This outburst, named GRB221009A, shook the world community of astrophysicists, who have since been analysing it to understand the physical phenomena that triggered this most intense burst of energy in our history.
Mar 17, 2023
Magnetars are neutron stars known for their wide variety of electromagnetic emissions coming from the dissipation of their extreme magnetic fields, which are the strongest known in the Universe and can reach 1015 Gauss, or 10 billion times that of the strongest magnet created by humans.
Sep 09, 2022
The origin of Galactic cosmic rays, their energy source and their acceleration process raise many questions more than 100 years after their discovery by Victor Hess in 1912. What are their sources of acceleration and energy? What are the acceleration mechanisms and their properties?
If these are not the only sources considered, strong shocks in supernova remnants constitute one of the privileged places of acceleration which allows the acceleration of particles by the mechanism of diffusive acceleration.
May 06, 2022
New numerical simulations probe the origin of type Ia supernovae
While type Ia supernovae are considered as highly symmetric supernovae, the explosion in a tight binary system composed of two white dwarfs revises this paradigm. An international team (Japan, Canada, France), including a researcher from the Department of Astrophysics/AIM Laboratory of CEA Paris-Saclay, publishes a study in the Astrophysical Journal that reveals that the distinctive asymmetric structures of such a supernova leave post-mortem imprints on the morphology of the ejected matter.
Apr 14, 2022
The Eclairs and MXT instruments of the SVOM mission delivered to CNES-Toulouse
The French teams of the ECLAIRs and MXT telescopes, instruments at the heart of the SVOM mission, experienced an important moment during March 2022. First, a general review of the two projects took place at CNES in Toulouse in front of a group of experts. This review allowed to verify that the two instruments meet the technical specifications and will be able to carry out the scientific mission.
Feb 17, 2022
The Fermi-LAT space telescope reveals the nature of particles accelerated in this historic supernova remnant.
The explosion of a star produces a shock wave that propagates at more than 5000 km/s for centuries and it is thought that these shocks are the main source of highly energetic particles called cosmic-rays. Studying the high-energy photon emission of supernova remnants allows us to probe the nature of the accelerated particles, their energy and their composition.
Dec 10, 2021
Successful of the calibration of the complete flighting model
The X-ray telescope MXT, one of the two instruments under French responsibility onboard the SVOM Chinese-French satellite payload, has just completed an important step in the project's progress, the calibration of the complete flying instrument.
Sep 14, 2021
On June 1, 2021, the open source software solution Gammapy was selected by the CTA (Cherenkov telescope array) observatory as a high-level analysis tool (Science Tools) for the reduction and modeling of the data collected by its future network of telescopes being deployed in Chile and the Canary Islands.
May 28, 2021
The MXT camera for the SVOM mission has just been assembled and delivered by the CEA
An X-ray camera, intended to equip the Sino-French SVOM satellite, has just been assembled and delivered by scientists and technicians from the Institute for Research on the Fundamental Laws of the Universe (CEA/Irfu). This high-tech prototype will capture high-energy photons (X-rays) emitted during the explosion of massive stars or the fusion of dense stars. The camera, particularly compact and innovative, integrates in a very limited volume, a complete detection chain, an active thermal control and a filter wheel.
May 27, 2021
Numerical simulations trace the origin of stellar black hole mergers
Since the interferometers of the LIGO-Virgo collaboration detected gravitational waves from the merging of two black holes, black hole binaries have been among the celestial objects that most interrogate scientists.
May 20, 2020
The fourth catalog of Fermi-LAT sources comes on line
The Fermi-LAT collaboration has published its fourth source catalog, named 4FGL. Based on eight years of data, it contains 5064 celestial objects emitting gamma rays at energies around 1 GeV, adding more than 2000 high-energy sources to the previous collection (published in 2015). More than one fourth of the objects are of unknown nature, calling for numerous follow-up studies.
Dec 21, 2019
The European Space Agency is shaping its science programme for the period 2035-2050
After the Horizon 2000 programme started in 1983, followed by its extension Horizon 2000 Plus, the European Space Agency (ESA) is committed until 2035 into the Cosmic Vision programme that includes the launches of Athena (2031) and LISA (2034). To plan its scientific priorities beyond this date, ESA has solicited the community through a call for ideas/projects.
Dec 04, 2019
The hot heart of the SN 1987A supernova
An international team, led by astronomers from Cardiff University, with the contribution of the Astrophysics Department of CEA-Irfu, may have spotted for the first time the compact remains of the last star explosion visible by eye that occurred on February 23, 1987 in a nearby galaxy, the Large Magellanic Cloud, only 160 000 light-years away.
Oct 06, 2019
Optical follow-up of gravitionnal waves
The first results of the space mission SVOM (for Space-based multi-band astronomical Variable Objects Monitor) have just fallen before the launch scheduled for the end of 2021. How is this possible? Quite simply because this ambitious Franco-Chinese mission, which aims at studying gamma-ray bursts of the Universe, is also developing a network of ground-based cameras able to detect the emission of visible light that follows the outbreak of these bursts, the most violent known explosions.
Jul 08, 2019
The LISA experiment will be able to detect planets throughout the Galaxy
The recent detections of gravitational waves, tiny vibrations of space-time, have opened a new window in the observation of the Universe. Two researchers, including Camilla Danielski from the Astrophysics Department of CEA-Irfu, have just demonstrated that, when these waves are emitted by two dense stars in orbit, they can be disturbed if a planet is in orbit around this pair of stars.
Mar 20, 2019
Two chimneys of hot gas found around the central back hole
Thanks to the X-ray satellites Chandra and XMM-Newton, an international team including the Department of Astrophysics of CEA-Irfu has just discovered the existence of two bubbles of hot gas escaping to distances of about 500 light-years, on both sides of the massive black hole environment, in the center of our galaxy.
Nov 08, 2018
Outstanding results from this Japanese X-rays observatory
Despite a short period of activity, the japanese space agency (Jaxa) Hitomi satellite has shown its full potential by delivering relevant information’s on several celestial objects.
May 10, 2018
THESEUS pre-selected for an ESA M5 mission
On May 7, 2018, the European Space Agency (ESA) announced the three selected space missions, out of the 25 proposed, for the fifth ESA middle class mission in its scientific program Cosmic Vision, whose launch date is planned in 2032. One of these three missions is the THESEUS project (Transient High-Energy Sky and Early Universe Surveyor), a project developed in recent years by a large European consortium in which the Astrophysics Department-AIM Laboratory of CEA-Irfu plays a major role.
Apr 09, 2018
The HESS international collaboration, to which CNRS and CEA contribute, has published the results of fifteen years of gamma ray observations of the Milky Way. Its telescopes installed in Namibia have studied populations of pulsar wind nebulae and supernova remnants, as well as microquasars, never before detected in gamma rays. These studies are supplemented by precise measurements such as those of the diffuse emission at the center of our Galaxy.
Feb 22, 2018
The very first moments of a star explosion
An unprecedented observation of a supernova, an explosion of a massive star, was captured in its early days by an amateur astronomer, at the exact moment when the supernova became visible in the sky.
Oct 16, 2017
The discovery of a new type of gravitational wave
Using a range of detectors developed with the participation of the CEA, physicists at CEA-Irfu have scrutinized the region from which the gravitational wave was detected on August 17, 2017 by LIGO-VIRGO facilities. Unlike the four previous detections of waves of the same type discovered since 2015, this new vibration of space, called GW170817, is of different origin. It does not result from the fusion of two black holes but of two densest known stars, the neutron stars.
Oct 06, 2017
The Cherenkov Telescope Array (CTA) consortium brings together 1300 scientists from 32 countries. They have published their scientific aims in a document over 200 pages long. This is the result of several years of work, and includes contributions from approximately fifteen Irfu researchers involved in X-ray and gamma-ray observatories (Fermi, Integral, XMM-Newton, H.E.S.S., etc.).
Jun 13, 2016
A laboratory scale-model of accretion column onto a highly magnetized dense star
Scientists from a large international collaboration (Oxford, AWE, CEA, LULI, Observatoire de Paris, University of Michigan, University of York and STFC Rutherford Appleton Laboratory) have succeeded for the first time in generating a laboratory analogue of a strong shock that is produced when matter falls at very high speed on the surface of extremely dense stars called white dwarfs.
Feb 29, 2016
An exceptional flaring activity from a galactic black hole revealed by the INTEGRAL satellite
Analysis of the high-energy emission from the microquasar V404 Cygni has lead to the discovery of gusts of electron and positron (the electron anti-particle) plasma. This amazing discovery was possible thanks to the exquisite sensitivity of the INTEGRAL/SPI spectrometer during a strong outburst of the source in June 2015. These findings show that microquasars can be very efficient to provide significant pairs electron-positron and thus can be considered somehow as “antimatter factories”.
Feb 17, 2016
Launch of the Japanese X-ray Astronomy satellite Astro-H
The X-ray astronomy satellite Astro-H was successfully launched on 17 February 2016 at 17H 45 (UT 8H45) from the JAXA Tanegashima Space Center in Japan. The satellite was put into orbit 14 min later and the first tests started. ASTRO-H is a JAXA / NASA mission under the Japanese leadership and with an ESA participation. This new observatory aims to observe and study the hot and energetic Universe. Astro-H embeds several instruments that when combined cover the spectral band 0.3-600 keV.
Jan 07, 2016
Recent change in the optical and gamma-ray polarization observed in the center of the Crab Nebula
The Crab Nebula, thought for decades to be a "standard candle", has recently seen this status challenged by the observation of intense high-energy gamma rays flares. An Irish and French team (centre for Astronomy of the Université of Galway and Service d’Astrophysique from CEA–Irfu ) has stressed this finding by observing for the first time a change of polarization in visible and gamma-ray light in the central region of the nebula from 2005 to 2012.
Jun 22, 2015
The enigma of the quasi-periodic oscillations
A team of researchers from CEA (Astrophysical Department and CEA-DAM) and the LUTH Laboratory (Paris Observatory) has just published a comprehensive study of an enigmatic phenomenon of quasi-periodic oscillations at the surface of strongly magnetic white dwarfs also called "Polars ". These dense stars are orbiting a companion and capture its material that falls freely toward the white dwarf poles. Strongly heated to millions of degrees, the hot gas or plasma then emits mainly in X-rays.
