Search results for "COSMOLOGY"
showing 10 items of 2905 documents
Search for anisotropic gravitational-wave backgrounds using data from Advanced LIGO and Advanced Virgo's first three observing runs
2021
We report results from searches for anisotropic stochastic gravitational-wave backgrounds using data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. For the first time, we include Virgo data in our analysis and run our search with a new efficient pipeline called {\tt PyStoch} on data folded over one sidereal day. We use gravitational-wave radiometry (broadband and narrow band) to produce sky maps of stochastic gravitational-wave backgrounds and to search for gravitational waves from point sources. A spherical harmonic decomposition method is employed to look for gravitational-wave emission from spatially-extended sources. Neither technique found eviden…
Neutron halos in excited states of 12 B
2018
An experiment was done to search for states with a neutron halo in 12 B. The measurements were carried out at the cyclotron of the University of Jyvaskyla (Finland) using Large Scattering Chamber (LSC). The idea of the work was to search for two states with the expected neutron halo, 1¯ and 2¯. Differential cross sections with excitation of 12 B states, including abovementioned states, were observed. The preliminary calculations on halo radii by the method of asymptotic normalization coefficients for the 2¯ and 1¯ states which are in a discrete spectrum gave following values: 5.6 fm and 7.4 fm, which is much larger than the radius of the valence neutron in the ground state. But strictly the…
Review of Particle Physics
2020
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,143 new measurements from 709 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, …
An X-ray characterization of the central region of the supernova remnant G332.5-5.6
2015
Aims. We present an X-ray analysis of the central region of supernova remnant (SNR) G332.5-5.6 through an exhaustive analysis of XMM-Netwon observations with complementary infrared observations. We characterize and discuss the origin of the observed X-ray morphology, which presents a peculiar plane edge over the west side of the central region. Methods. The morphology and spectral properties of the X-ray SNR were studied using a single full frame XMM-Netwon observation in the 0.3 to 10.0 keV energy band. Archival infrared WISE observations at 8, 12 and 24 μm were also used to investigate the properties of the source and its surroundings at different wavelengths. Results. The results show th…
Sub-milliarcsecond imaging of a bright flare and ejection event in the extragalactic jet 3C 111
2020
Context. Flares in radio-loud active galactic nuclei are thought to be associated with the injection of fresh plasma into the compact jet base. Such flares are usually strongest and appear earlier at shorter radio wavelengths. Hence, very long baseline interferometry (VLBI) at millimeter(mm)-wavelengths is the best-suited technique for studying the earliest structural changes of compact jets associated with emission flares. Aims. We study the morphological changes of the parsec-scale jet in the nearby (z = 0.049) γ-ray bright radio galaxy 3C 111 following a flare that developed into a major radio outburst in 2007. Methods. We analyse three successive observations of 3C 111 at 86 GHz with th…
On the location of the supermassive black hole in CTA102
2015
Relativistic jets in active galactic nuclei represent one of the most powerful phenomena in the Universe. They form in the surroundings of the supermassive black holes as a by-product of accretion onto the central black hole in active galaxies. The flow in the jets propagates at velocities close to the speed of light. The distance between the first part of the jet that is visible in radio images (core) and the black hole is still a matter of debate. Only very-long-baseline interferometry observations resolve the innermost compact regions of the radio jet. Those can access the jet base, and combining data at different wavelenghts, address the physical parameters of the outflow from its emiss…
Octave Spanning Supercontinuum in Titanium Dioxide Waveguides
2018
International audience; We report on the experimental generation of an octave-spanning supercontinuum in a 2.2 cm-long titanium dioxide optical waveguide with two zero dispersion wavelengths. The resulting on-chip supercontinuum reaches the visible wavelength range as well as the mid-infrared region by using a femtosecond fiber laser pump at 1.64 µm.
UV variability and accretion in NGC 2264
2015
Photometric variability is a distinctive feature of young stellar objects; exploring variability signatures at different wavelengths provides insight into the physical processes at work in these sources. We explore the variability signatures at ultraviolet (UV) and optical wavelengths for several hundred accreting and non-accreting members of the star-forming region NGC 2264 (~3Myr). Cone search capability for table J/A+A/581/A66/table2 (Median photometry, variability amplitudes, light curve rms, J index, and color slopes for members monitored at CFHT)
15GHz and jet properties of MOJAVE blazars
2013
We investigate the Fermi Large Area Telescope {gamma}-ray and 15GHz Very Long Baseline Array radio properties of a joint {gamma}-ray and radio-selected sample of active galactic nuclei (AGNs) obtained during the first 11 months of the Fermi mission (2008 August 4-2009 July 5). Our sample contains the brightest 173 AGNs in these bands above declination -30{deg} during this period, and thus probes the full range of {gamma}-ray loudness ({gamma}-ray to radio band luminosity ratio) in the bright blazar population. The latter quantity spans at least 4 orders of magnitude, reflecting a wide range of spectral energy distribution (SED) parameters in the bright blazar population. The BL Lac objects,…
1.5Jy MOJAVE AGN sample and 3FGL data
2016
We use the complete MOJAVE 1.5Jy sample of active galactic nuclei (AGNs) to examine the gamma-ray detection statistics of the brightest radio-loud blazars in the northern sky. We find that 23% of these AGNs were not detected above 0.1GeV by the Fermi-LAT during the four-year 3FGL catalog period partly because of an instrumental selection effect and partly due to their lower Doppler boosting factors. Blazars with synchrotron peaks in their spectral energy distributions located below 10^13.4^Hz also tend to have high-energy peaks that lie below the 0.1GeV threshold of the LAT, and are thus less likely to be detected by Fermi. The non-detected AGNs in the 1.5Jy sample also have significantly l…