Acronym for New Extension in Nançay Upgrading LoFAR, NenuFAR is an array of nearly 2,000 antennas deployed over an area of 60,000 m2 in Nançay, on the radio astronomy station of Paris Observatory, within the scientific unit of Nançay - USN (Observatoire de Paris - PSL / Université d’Orléans/ CNRS).
NenuFAR is already operational with more than 1000 antennas and will keep expanding. On Monday, July 1, 2019, it began its major observation programs : birth of galaxies, magnetized exoplanets, pulsars, solar flares... About fifteen programs were proposed by 140 French and foreign scientists for the Early Science phase.
NenuFAR observes the sky in radio waves, at the lowest frequencies observable from the ground : from 10 to 85 MHz, or 3.5 to 30 m wavelength, making it the most powerful instrument on the planet in its frequency band.
NenuFAR electronically combines the signals from its thousands of antennas to point the celestial source of interest to produce images (intensity maps based on coordinates in the sky) and dynamic spectra (intensity maps based on time and frequency). Its antennas benefit from a very high performance preamplifier, developed jointly by the Subatech laboratory in Nantes (ITM Atlantique / Université de Nantes/ CNRS) and the Radioastronomy Station in Nançay. Its receptors also result from an original development. A user interface has been specifically developed for the programming of this complex instrument.
NenuFAR will operate in 3 modes :
- a wide field imaging mode,
- a multibeam mode dedicated to temporal and spectral studies, such as those of pulsars (hyperdense and highly magnetized dead stars in rapid rotation) and transient sources,
- a high-resolution imaging mode by coupling with the 50 European LOFAR (LOw Frequency ARray) radio telescope stations, whose core is located in the Netherlands.
NenuFAR’s main scientific objectives are : radio detection and study of exoplanets orbiting around other stars ; the signal of the Cosmic Dawn, the moment of the formation of the first stars and galaxies, 100 to 200 million years after the Big Bang ; and the study of pulsars. Many other studies are planned : radio emissions from eruptive or magnetized stars, galaxies and galaxy clusters, spectral lines in the interstellar medium, lightning from planetary storms, radio bursts from the Jupiter magnetosphere and the Sun.
As no other radio telescope has yet observed in this frequency band with such sensitivity, there is real hope of discovering new types of radio sources, for example signals related to the catastrophic events causing the emission of gravitational waves.
Through its commitment to LOFAR, NenuFAR has been labelled by the Ministry of Higher Education, Research and Innovation as a ″Research Infrastructure″. It is also an official pathfinder of the future world’s largest radio telescope, the Square Kilometre Array (SKA).
The main laboratories supporting the development of NenuFAR are LESIA (Observatoire de Paris - PSL / CNRS / Sorbonne Université / Université Paris Diderot), the scientific unit of Nançay - USN (Observatoire de Paris - PSL / Université d’Orléans/ CNRS) and LPC2E (Université d’Orléans / CNRS / CNES).
The Early Science phase, scheduled until the end of 2021, will combine scientific observations with the completion of the construction and development of the instrument. The official inauguration of NenuFAR will take place on October 3, 2019.
Collaboration
The development of NenuFAR has been supported in terms of personnel and funding by the Radioastronomy Station of Nancay, CNRS, the Observatoire de Paris - PSL, the University of Orléans, the Observatoire des Sciences de l’Univers en région Centre, the Région Centre-Val de Loire, the DIM-ACAV and DIM-ACAV+ of the Île-de-France Region, and the Agence Nationale de la Recherche.
