Search results for "Astrophysics"
showing 10 items of 8341 documents
Modelling regional-scale attenuation across Italy and the Tyrrhenian Sea
2021
Abstract Modelling regional-scale attenuation of seismic waves at ~1 Hz is challenging, especially when these waves propagate across both continental and oceanic crust. Recent developments in seismic imaging and modelling have provided us with the computational tools necessary to reconstruct these mixed settings using deterministic (coherent) and stochastic (coda) information. Here, we present new tomographic maps of coda-attenuation for both the Italian peninsula and the Tyrrhenian Sea. Kernel-based coda attenuation imaging in the diffusive approximation is tested in the oceanic environment, highlighting a non-diffusive behaviour across the Southern Tyrrhenian Sea. Joint deterministic and …
Charged and Neutral Current Neutrino Induced Nucleon Emission Reactions
2006
Presented by J. Nieves at the XX Max Born Symposium “Nuclear Effects in Neutrino Interactions”, Wrocław, Poland, December 7–10, 2005.
Trigger and aperture of the surface detector array of the Pierre Auger Observatory
2010
The surface detector array of the Pierre Auger Observatory consists of 1600 water-Cherenkov detectors, for the study of extensive airshowers (EAS) generated by ultra-high-energy cosmic rays. We describe the trigger hierarchy, from the identification of candidates howers at the level of a single detector, amongst a large background (mainly random single cosmic ray muons), up to the selection of real events and the rejection of random coincidences. Such trigger makes the surface detector array fully efficient for the detection of EAS with energy above 3 x 1018 eV, for all zenith angles between 03 and 603, independently of the position of the impact point and of the mass of the primary particl…
Quasi-periodic dipping in the ultraluminous X-ray source, NGC 247 ULX-1
2021
Most ultraluminous X-ray sources (ULXs) are believed to be stellar mass black holes or neutron stars accreting beyond the Eddington limit. Determining the nature of the compact object and the accretion mode from broadband spectroscopy is currently a challenge, but the observed timing properties provide insight into the compact object and details of the geometry and accretion processes. Here we report a timing analysis for an 800 ks XMM-Newton campaign on the supersoft ultraluminous X-ray source, NGC 247 ULX-1. Deep and frequent dips occur in the X-ray light curve, with the amplitude increasing with increasing energy band. Power spectra and coherence analysis reveals the dipping preferential…
Spectra and essential spectral radii of composition operators on weighted Banach spaces of analytic functions
2008
AbstractWe determine the spectra of composition operators acting on weighted Banach spaces Hv∞ of analytic functions on the unit disc defined for a radial weight v, when the symbol of the operator has a fixed point in the open unit disc. We also investigate in this case the growth rate of the Koenigs eigenfunction and its relation with the essential spectral radius of the composition operator.
Search for transient sources with the ANTARES and KM3NeT neutrino telescopes in the multi-messenger astronomy era
2020
En el presente manuscrito se expone el trabajo realizado en el seno de la Collaboración ANTARES-KM3NeT sobre la astronomía multi-mensanjero con neutrinos, que se ha enfocado en dos ejes: la detección de neutrinos de supernova a bajas energías (MeV) con los telecopios KM3NeT y la búsqueda de neutrinos de alta energía (TeV-PeV) en ANTARES en coincidencia con fuentes transitorias detectadas en ondas gravitationales o rayos gamma de muy alta energía O(TeV). El primer análisis, explora la capacidad de los telescopios de neutrinos KM3NeT para detectar la señal de una explosión de supernova (CCSN), así como el potencial de explotar dicha detección para aprender sobre la física que hay detrás, en p…
Zvaigžņu aicinājums: Latvijas Universitātes astronomijas studentu (1920-1949) dzīvesstāsti
2021
Grāmatā ievietota 51 Latvijas Universitātes astronomijas studenta (1920 – 1949) īsa biogrāfija. Divdesmit kādreizējie astronomijas studenti kļuva par profesionāliem astronomiem, matemātiķiem vai fiziķiem tepat Latvijā vai trimdā, daļa kļuva par pazīstamiem pedagogiem. Par pārējiem astronomijas studentiem, kopskaitā 31, grāmatā vienkop un izvērsti stāstīts pirmo reizi. Biogrāfijas papildina vizuālais materiāls, kas vēsta par Latvijas Universitātes Astronomiskās observatorijas vēsturi 20. gs. 20. un 30. gados.
"Table 4" of "J/$\psi$ elliptic flow in Pb-Pb collisions at $\mathbf{\sqrt{s_{\rm NN}}}$ = 5.02 TeV"
2017
Transverse momentum dependence of inclusive J/$\psi$ $v_2$ at $\sqrt{s_{\rm NN}}=5.02$ TeV for the 40-60% centrality class (forward rapidity). The first uncertainty (stat) is statistical, the second (sys,uncorrel) is the uncorrelated systematic, while the third one (sys,correl) is a $p_{\rm T}$-correlated systematic uncertainty.
"Table 2" of "J/$\psi$ elliptic flow in Pb-Pb collisions at $\mathbf{\sqrt{s_{\rm NN}}}$ = 5.02 TeV"
2017
Transverse momentum dependence of inclusive J/$\psi$ $v_2$ at $\sqrt{s_{\rm NN}}=5.02$ TeV for the 20-40% centrality class (mid-rapidity). The first uncertainty (stat) is statistical, the second (sys,uncorrel) is the uncorrelated systematic, while the third one (sys,correl) is a $p_{\rm T}$-correlated systematic uncertainty.
"Table 1" of "J/$\psi$ elliptic flow in Pb-Pb collisions at $\mathbf{\sqrt{s_{\rm NN}}}$ = 5.02 TeV"
2017
Transverse momentum dependence of inclusive J/$\psi$ $v_2$ at $\sqrt{s_{\rm NN}}=5.02$ TeV for the 20-40% centrality class (forward rapidity). The first uncertainty (stat) is statistical, the second (sys,uncorrel) is the uncorrelated systematic, while the third one (sys,correl) is a $p_{\rm T}$-correlated systematic uncertainty.