Search results for "GAL"
showing 10 items of 9260 documents
Population Properties of Compact Objects from the Second LIGO-Virgo Gravitational-Wave Transient Catalog
2021
Abbott, R., et al. (LIGO and Virgo Collaboration)
Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3a
2022
Abbott, R., et al. (LIGO and VIRGO Collaboration)
The advanced Virgo longitudinal control system for the O2 observing run
2020
Following a successful period of data-taking between 2006 and 2011, the Virgo gravitational-wave detector was taken offline for a major upgrade. The changes made to the instrument significantly increased the complexity of the control systems and meant that an extended period of commissioning was required to reach a sensitivity appropriate for science data-taking. This commissioning period was completed in July of 2017 and the second-generation Advanced Virgo detector went on to join the Advanced LIGO detectors in the O2 science run in August of the same year. The upgraded detector was approximately twice as sensitive to binary neutron star mergers as the first-generation instrument. During …
GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
2017
On August 17, 2017 at 12-41:04 UTC the Advanced LIGO and Advanced Virgo gravitational-wave detectors made their first observation of a binary neutron star inspiral. The signal, GW170817, was detected with a combined signal-to-noise ratio of 32.4 and a false-alarm-rate estimate of less than one per 8.0×104 years. We infer the component masses of the binary to be between 0.86 and 2.26 M, in agreement with masses of known neutron stars. Restricting the component spins to the range inferred in binary neutron stars, we find the component masses to be in the range 1.17-1.60 M, with the total mass of the system 2.74-0.01+0.04M. The source was localized within a sky region of 28 deg2 (90% probabili…
New orbital ephemerides for the dipping source 4U 1323-619: Constraining the distance to the source
2016
4U 1323-619 is a low mass X-ray binary system that shows type I X-ray bursts and dips. The most accurate estimation of the orbital period is 2.941923(36) hrs and a distance from the source that is lower than 11 kpc has been proposed. We aim to obtain the orbital ephemeris, the orbital period of the system, as well as its derivative to compare the observed luminosity with that predicted by the theory of secular evolution. We took the advantage of about 26 years of X-ray data and grouped the selected observations when close in time. We folded the light curves and used the timing technique, obtaining 12 dip arrival times. We fit the delays of the dip arrival times both with a linear and a quad…
New species of Deinogalerix (Mammalia, Eulipotyphla) from the late Miocene of Scontrone (Abruzzo, central Italy)
2017
Deinogalerix is a typical component of the late Miocene insular fauna of Gargano (south-eastern Italy). Remains of this taxon had also been found over the last 20 years at the early Tortonian site of Scontrone (Abruzzo, central Italy), but they had never been described in detail. Two new species are introduced. One of them, D. samniticus sp. nov., is larger sized and better documented, and received a formal description. The other entity is clearly distinct from D. samniticus sp. nov., but it is merely represented by a single mandible. It is therefore presented here as a different, but undetermined species, Deinogalerix sp. Comparative analyses show that the new species have exclusive dental…
Computational Structures and SAPT Interaction Energies of HXeSH···H2Y (Y=O or S) Complexes
2018
Ab initio calculations of the structures, vibrational spectra and supermolecular and symmetry-adapted perturbation theory (SAPT) interaction energies of the HXeOH and HXeSH complexes with H2O and H2S molecules are presented. Two minima already reported in the literature were reproduced and ten new ones were found together with some transition states. All complexes show blue shift in Xe&ndash
Bezdarbs Latgales reģionā
2018
Bakalaura darba tēma ir “Bezdarbs Latgales reģionā”. Bakalaura darba apjoms ir 76 lpp., kurās ir izvietoti 49 attēli, 3 tabulas, 1 pielikums. Darba gaitā tika izmantots 31 literatūras avots. Bakalaura darba pētāmā problēma ir Latgales bezdarba situācijas izcelšanās citu Latvijas reģionu starpā. Bakalaura darba tēma ir aktuāla, jo Latgales reģiona bezdarba problēma palēnina ne vien Latgales ekonomisko un saimniecisko attīstības dinamiku, bet visas Latvijas valsts labklājības pastiprināšanos, kā arī izraisa nelabvēlīgas demogrāfisko procesu sekas. Izvirzītais bakalaura darba mērķis ir, pamatojoties uz teorētiskajām atziņām, statistisko datu analīzi un respondentu aptauju, novērtēt Latgales re…
Nerezidentu noguldījumi Latvijas komercbankās: tendences un riski
2016
Bakalaura darba tēma ir “Nerezidentu noguldījumi Latvijas komercbankās- tendences un riski”. Darba mērķis ir analizējot Latvijas likumdošanu, noguldījumu portfeli un tā segmetus, kā arī nerezidentu noguldījumu tendences un riskus laika periodā no 2009.līdz 2015.gadam, secināt kādas ir iespējas un tai pašā laikā draudi saistīti ar nerezidentu noguldījumiem, kā arī izstrādāt priekšlikumus noguldījumu piesaistei komercbankās un ar nerezidentu noguldījumiem saistīto risku mazināšanai. Darbs sastāv no 3 nodaļām un 8 apakšnodaļām. Pirmajā nodaļā apskatīts noguldījumu teorētiskais raksturojums. Otrajā nodaļā tiek analizēts noguldījumu portfelis Latvijas komercbankās. Trešajā nodaļā analizētas nere…
Inference of proto-neutron star properties from gravitational-wave data in core-collapse supernovae
2021
The eventual detection of gravitational waves from core-collapse supernovae (CCSN) will help improve our current understanding of the explosion mechanism of massive stars. The stochastic nature of the late post-bounce gravitational wave signal due to the non-linear dynamics of the matter involved and the large number of degrees of freedom of the phenomenon make the source parameter inference problem very challenging. In this paper we take a step towards that goal and present a parameter estimation approach which is based on the gravitational waves associated with oscillations of proto-neutron stars (PNS). Numerical simulations of CCSN have shown that buoyancy-driven g-modes are responsible …