Search results for "raga"
showing 10 items of 1852 documents
Energy transfer in diiodoBodipy-grafted upconversion nanohybrids.
2015
Steady-state and time-resolved emission studies on nanohybrids consisting of NaYF4:Yb,Er and a diiodo-substituted Bodipy (UCNP-IBDP) show that the Yb(3+) metastable state, formed after absorption of a near-infrared (NIR) photon, can decay via two competitive energy transfer processes: sensitization of IBDP after absorption of a second NIR photon and population of Er(3+) excited states.
Glyphosate-based herbicide use affects individual microbial taxa in strawberry endosphere but not the microbial community composition
2023
AbstractAimsIn a field study, the effects of treatments of glyphosate-based herbicides (GBHs) in soil, alone and in combination with phosphate fertilizer, were examined on the performance and endophytic microbiota of garden strawberry.Methods and resultsThe root and leaf endophytic microbiota of garden strawberries grown in GBH-treated and untreated soil, with and without phosphate fertilizer, were analyzed. Next, bioinformatics analysis on the type of 5-enolpyruvylshikimate-3-phosphate synthase enzyme was conducted to assess the potential sensitivity of strawberry-associated bacteria and fungi to glyphosate, and to compare the results with field observations. GBH treatments altered the abu…
Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009
2017
Astronomy and astrophysics 603, A31 (2017). doi:10.1051/0004-6361/201629540
Detection of cosmic filaments using the Candy model
2004
We propose to apply a marked point process to automatically delineate filaments of the large-scale structure in redshift catalogues. We illustrate the feasibility of the idea on an example of simulated catalogues, describe the procedure, and characterize the results. We find the distribution of the length of the filaments, and suggest how to use this approach to obtain other statistical characteristics of filamentary networks.
Stellar populations of galaxies in the ALHAMBRA survey up toz ∼ 1
2018
Aims. We aim at constraining the stellar population properties of quiescent galaxies. These properties reveal how these galaxies evolved and assembled since z similar to 1 up to the present time. Methods. Combining the ALHAMBRA multi-filter photo-spectra with the fitting code for spectral energy distribution MUFFIT (MUlti-Filter FITting), we built a complete catalogue of quiescent galaxies via the dust-corrected stellar mass vs. colour diagram. This catalogue includes stellar population properties, such as age, metallicity, extinction, stellar mass, and photometric redshift, retrieved from the analysis of composited populations based on two independent sets of simple stellar population (SSP…
Cosmological Implications of some Nonstandard Particle Physics Models
2012
The standard cosmological model has been very successful in describing the evolution of the Universe from the first seconds until today. However, some challenges still remain concerning the nature of some of its components as well as observationally probing some of the periods of its expansion. In this thesis we discuss what are probably the three least known components of the Universe: neutrinos, dark matter, and dark energy. In particular, concerning the neutrino sector, we place limits on the relic neutrino asymmetries using some of the latest cosmological data, taking into account the effect of flavor oscillations. We find that the present bounds are still dominated by the limits coming…
Pinpointing the SMBH in NGC1052
2016
Supermassive black holes (SMBH) are essential for the production of jets in radio-loud active galactic nuclei (AGN). Theoretical models based on Blandford & Znajek (1977MNRAS.179..433B) extract the rotational energy from a Kerr black hole, which could be the case for NGC1052, to launch these jets. This requires magnetic fields on the order of 1000G to 10000G. We imaged the vicinity of the SMBH of the AGN NGC1052 with the Global Millimetre VLBI Array and found a bright and compact central feature that is smaller than 1.9 light days (100 Schwarzschild radii) in radius. Interpreting this as a blend of the unresolved jet bases, we derive the magnetic field at 1 Schwarzschild radius to lie betwe…
Sub-milliarcsecond imaging of 3C111
2020
Flares in radio-loud active galactic nuclei (AGNs) 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) gamma-ray bright radio galaxy 3C 111 following a flare that developed into a major radio outburst in 2007. We analyse three successive observations of 3C 111 at 86 GHz with the Global…
MOJAVE. VI. Kinematic analysis of blazar jets
2012
We discuss the jet kinematics of a complete flux-density-limited sample of 135 radio-loud active galactic nuclei (AGNs) resulting from a 13 year program to investigate the structure and evolution of parsec-scale jet phenomena. Our analysis is based on new 2cm Very Long Baseline Array (VLBA) images obtained between 2002 and 2007, but includes our previously published observations made at the same wavelength, and is supplemented by VLBA archive data. In all, we have used 2424 images spanning the years 1994-2007 to study and determine the motions of 526 separate jet features in 127 jets. Cone search capability for table J/AJ/138/1874/agn (AGN sample)
22GHz image of 3C 273
2017
RadioAstron is a 10m orbiting radio telescope mounted on the Spektr-R satellite, launched in 2011, performing Space Very Long Baseline Interferometry (SVLBI) observations supported by a global ground array of radio telescopes. With an apogee of ~350000km, it is offering for the first time the possibility to perform as-resolution imaging in the cm-band. The RadioAstron Active Galactic Nuclei (AGN) polarization Key Science Project (KSP) aims at exploiting the unprecedented angular resolution provided by RadioAstron to study jet launching/collimation and magnetic-field configuration in AGN jets. The targets of our KSP are some of the most powerful blazars in the sky. We present observations at…