A5103102913- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Astrophysics and Star Formation Studies
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Astronomical Observations and Instrumentation
- Radio Wave Propagation Studies
- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Scientific Research and Discoveries
- Antenna Design and Optimization
- Geophysics and Gravity Measurements
- Impact of Light on Environment and Health
- Composite Structure Analysis and Optimization
- Astrophysical Phenomena and Observations
- Fluid Dynamics Simulations and Interactions
- Graphene and Nanomaterials Applications
- Soil Moisture and Remote Sensing
- Gaussian Processes and Bayesian Inference
University of Guilan
2009-2024
Centre National de la Recherche Scientifique
2015-2024
Laboratoire de Physique des 2 Infinis Irène Joliot-Curie
2020-2024
Institut National de Physique Nucléaire et de Physique des Particules
2010-2024
Université Paris-Saclay
2011-2024
Université Paris Cité
2003-2023
Astrophysique, Instrumentation et Modélisation
2023
CEA Paris-Saclay
2023
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2023
Université Paris-Sud
2009-2020
(Abridged) We describe here the most ambitious survey currently planned in optical, Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST have unique capability faint time domain. The design is driven four main themes: probing dark energy matter, taking an inventory Solar System, exploring transient optical sky, mapping Milky Way. wide-field ground-based system sited at Cerro Pach\'{o}n northern Chile. telescope 8.4 m...
Aims. The EROS-2 project was designed to test the hypothesis that massive compact halo objects (the so-called "machos") could be a major component of dark matter Milky Way galaxy. To this end, monitored over 6.7 years stars in Magellanic clouds for microlensing events caused by such objects.
We describe the processing of 336 billion raw data samples from High Frequency Instrument (HFI) which we performed to produce six temperature maps first 295 days Planck-HFI survey data. These provide an accurate rendition sky emission at 100, 143, 217, 353, 545 and 857 GHz with angular resolution ranging 9.9 4.4^2. The white noise level is around 1.5 μK degree or less in 3 main CMB channels (100--217GHz). photometric accuracy better than 2% frequencies between 100 353 7% two highest...
We searched for long-duration microlensing events originating from intermediate-mass black holes (BH) in the halo of Milky Way, using archival data EROS-2 and MACHO photometric surveys towards Large Magellanic Cloud (LMC). combined these two to create a common database light curves 14.1 million objects LMC, covering total duration 10.6 years, with flux series measured four wide passbands. carried out search on curves, complemented by 22.7 objects, observed only or MACHO, over about 7 A...
We analyze the cosmological constraints that Archeops (Benoît et al. 2003) places on adiabatic cold dark matter models with passive power-law initial fluctuations.Because its angular power spectrum has small bins in and large coverage down to COBE scales, provides a precise determination of first acoustic peak terms position at multipole l = 220 ± 6, height width.An analysis data combination other CMB datasets constrains baryon content Universe, Ω b h 2 0.022 +0.003 -0.004 , compatible...
The cosmic
Five years of eros data towards the Small Magellanic Cloud have been searched for gravitational microlensing events, using a new, more accurate method to assess impact stellar blending on efficiency. Four long-duration candidates found which, if they are hint at non-halo population lenses. Combined with results from other observation programs, this analysis yields strong limits amount Galactic dark matter made compact objects. Less than 25% standard halo can be composed objects mass between...
Large Scale Structures (LSS) in the universe can be traced using neutral atomic hydrogen HI through its 21cm emission. Such a 3D matter distribution map used to test Cosmological model and constrain Dark Energy properties or equation of state. A novel approach, called intensity mapping distribution, radio interferometers with large instantaneous field view waveband. In this paper, we study sensitivity different interferometer configurations, multi-beam instruments for observation scale...
This white paper envisions a revolutionary post-DESI, post-LSST dark energy program based on intensity mapping of the redshifted 21cm emission line from neutral hydrogen at radio frequencies. The proposed survey has unique capability to quadruple volume Universe surveyed by optical programs, provide percent-level measurement expansion history $z \sim 6$, open window explore physics beyond concordance $Λ$CDM model, and significantly improve precision standard cosmological parameters. In...
The Tianlai Dish Pathfinder Array is a radio interferometer designed to test techniques for 21~cm intensity mapping in the post-reionization universe as means measuring large-scale cosmic structure. It performs drift scans of sky at constant declination. We describe design, calibration, noise level, and stability this instrument based on analysis about $\sim 5 \%$ 6,200 hours on-sky observations through October, 2019. Beam pattern determinations using drones transit bright sources are good...
We fit the data for binary lens microlensing event MACHO 98-SMC-1 from five different collaborations and find two distinct solutions characterized by separation d mass ratio q: (d,q) = (0.54,0.50) (3.65,0.36), where is in units of Einstein radius. However, relative proper motion very similar solutions, 1.30 km s-1 kpc-1 1.48 kpc-1, thus confirming that Small Magellanic Cloud. The close can be either rotating or approximately static but wide must at to its maximum allowed rate consistent with...
We present the first determination of Galactic polarized emission at 353 GHz by Archeops.The data were taken during Arctic night February 7, 2002 after balloon-borne instrument was launched CNES from Swedish Esrange base near Kiruna.In addition to 143 and 217 frequency bands dedicated CMB studies, Archeops had one 545 six bolometers mounted in three polarization-sensitive pairs that used for foreground studies.We maps I, Q, U Stokes parameters over 17% sky with a 13 arcmin resolution (850...
R Coronae Borealis stars (RCB) are a rare type of evolved carbon-rich supergiant that increasingly thought to result from the merger two white dwarfs, called Double degenerate scenario. This scenario is also studied as source, at higher mass, Ia Supernovae (SnIa) explosions. Therefore better understanding RCBs composition would help constrain simulations such events. We searched for and RCB in EROS Magellanic Clouds database. extended our research DY Per (DYPers) expected be cooler (T~3500...
We present a measurement of the microlensing optical depth toward Galactic bulge based on analysis 15 contiguous fields centered and containing clump-giant stars (belonging to extended clump area) monitored during almost three seasons by EROS (Expérience de Recherche d'Objets Sombres). find averaged over all fields, 16 events with giants as sources. This value is substantially below several other determinations MACHO OGLE groups more in agreement what expected from axisymmetric...