Description du projet
Les rayons gamma au service de la compréhension des ondes gravitationnelles
La détection et la caractérisation des ondes gravitationnelles (OG) à basse fréquence permettent d’éclairer d’importantes questions ouvertes en physique, en astronomie et en cosmologie. Historiquement, les scientifiques ont utilisé des radiotélescopes pour rechercher un bruit de fond d’OG, mais le bruit, provenant principalement du milieu interstellaire, complique les mesures. Le projet GIGA, financé par le CER, vise à exploiter les rayons gamma, qui ne sont pas affectés par ce bruit, pour surmonter cet obstacle. Le projet vise à créer un ensemble d’étoiles à neutrons en rotation extrêmement stables afin d’étudier l’arrière-plan d’OG. L’équipe mesurera également les propriétés du milieu interstellaire et explorera les couplages de la matière noire en fonction de l’énergie. Les résultats devraient permettre de mieux comprendre la dynamique des trous noirs supermassifs et de leurs galaxies hôtes.
Objectif
When galaxies merge, do their central supermassive black holes also merge? How does the merger affect star formation and the evolution of galaxies? How does physics beyond the Standard Model of particles affect the Universe? The detection and characterisation of low-frequency gravitational waves (GWs) will address these fundamental and longstanding questions of astronomy and cosmology.
Supermassive black holes at the centres of merging galaxies are expected to form binary systems whose orbital motion generates GWs. A cosmological population of such systems combine to build up a GW background (GWB). Such a GWB is also expected if the Universe went through an inflationary period, providing a GW map just moments after the Big Bang. Pulsar timing arrays (PTAs), which are ensembles of extremely stable millisecond pulsars (rotating neutron stars), can be used to study this GWB.
Searches for the GWB have typically used sensitive radio telescopes. However, radio data exhibit complex noise processes, predominantly arising from the interstellar medium (ISM), that limit its sensitivity and introduce bias. Gamma rays are immune to the effects of the ISM and a gamma-ray PTA can overcome several of the limitations affecting radio data. GIGA will (a) establish a gamma-ray PTA and independently detect the GWB, (b) develop advanced inference techniques to distinguish its astrophysical origins, (c) measure properties of the ISM through multiwavelength studies, and (d) explore energy-dependent couplings of dark matter. Through these avenues, GIGA will also maximise the sensitivity of radio PTAs and provide crucial validation of their measurements.
The detection of the GWB will provide the first stringent constraints on the dynamical evolution of supermassive black holes and their host galaxies while advanced inferences techniques will aid in disentangling weaker astrophysical sources including cosmic strings and phase transitions, thus probing physics beyond the Standard Model.
Champ scientifique
- natural sciencesphysical sciencesastronomyobservational astronomygravitational waves
- natural sciencesphysical sciencesastronomyobservational astronomyradio astronomy
- natural sciencesphysical sciencesastronomyphysical cosmologybig bang
- natural sciencesphysical sciencesastronomyastrophysicsblack holes
- natural sciencesphysical sciencesastronomyplanetary sciencescelestial mechanics
Mots‑clés
Programme(s)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Thème(s)
Régime de financement
HORIZON-ERC - HORIZON ERC GrantsInstitution d’accueil
3526 KV Utrecht
Pays-Bas