Institut de Ciències del Cosmos (ICCUB): Enviaments recents
Ara mostrant els elements 1-20 de 1020
Anomalous quantum transport in fractal lattices
Fractal lattices are self-similar structures with repeated patterns on different scales. Quantum transport through such structures is subtle due to the possible co-existence of localized and extended states. Here, we study ...
Superfluid rings as quantum pendulums
A nondispersive quantum pendulum is presented. The proposed setup consists of an ultracold atomic cloud, featuring attractive interatomic interactions, loaded into a tilted ring potential. The classical and quantum domains ...
Spectroscopic age estimates for APOGEE red-giant stars: Precise spatial and kinematic trends with age in the Galactic disc
Over the last few years, many studies have found an empirical relationship between the abundance of a star and its age. Here we estimate spectroscopic stellar ages for 178 825 red-giant stars observed by the APOGEE survey ...
Using clustering for disperse objects fields segmentation in MIRADAS instrument
Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS) is a near-infrared multi-object spectrograph for Gran Telescopio Canarias (GTC). It has 12 deployable Integral Field Units (IFU) based on probe arms with pick-off ...
Statistical detection of tidal streams generated by globular clusters and their application to measure the axis ratio of the Milky Way dark matter halo
[eng] In this thesis we have presented a new method to search for tidal streams generated by globular clusters in the Gaia catalogue. This statistical method is based on the maximum likelihood technique to distinguish ...
Gaia's Cepheids and RR Lyrae stars and luminosity calibrations based on Tycho-Gaia Astrometric Solution
Gaia Data Release 1 contains parallaxes for more than 700 Galactic Cepheids and RR Lyrae stars, computed as part of the Tycho-Gaia Astrometric Solution (TGAS). We have used TGAS parallaxes, along with literature (V, I, J, ...
Enhancing the detection of low-energy M dwarf flares: wavelet-based denoising of CHEOPS data
Stellar flares are powerful bursts of electromagnetic radiation triggered by magnetic reconnection in the chromosphere of stars, occurring frequently and intensely on active M dwarfs. While missions like TESS and Kepler ...
C60 fullerene as an on-demand single photon source at room temperature
Single photon sources are fundamental for applications in quantum computing, secure communication, and sensing, as they enable the generation of individual photons and ensure strict control over photon number statistics. ...
New high-sensitivity, milliarcsecond resolution results from routine observations of lunar occultations at the ESO VLT
Context. Lunar occultations (LO) are a very efficient and powerful technique that achieves the best combination of high angular resolution and sensitivity possible today at near-infrared wavelengths. Given that the events ...
Two waves of massive stars running away from the young cluster R136
Massive stars are predominantly born in stellar associations or clusters [1]. The irradiation fields, stellar winds, and supernovae strongly impact their local environment. In the first few million years of a cluster’s ...
Final state rescattering effects in axio-hadronic η and η' decays
It has been long-understood that final state rescattering effects provide O(1) corrections to hadronic meson decays rates, such as η →πππ and η′→ηππ. Hence, one would expect that such effects would be just as important in ...
The impact of human expert visual inspection on the discovery of strong gravitational lenses
We investigate the ability of human ‘expert’ classifiers to identify strong gravitational lens candidates in Dark Energy Survey like imaging. We recruited a total of 55 people that completed more than 25 per cent of the ...
Euclid: Searching for pair-instability supernovae with the Deep Survey
Pair-instability supernovae are theorized supernovae that have not yet been observationally confirmed. They are predicted to exist in low-metallicity environments. Because overall metallicity becomes lower at higher ...
TDCOSMO: IX. Systematic comparison between lens modelling software programs: Time-delay prediction for WGD 2038-4008
The importance of alternative methods for measuring the Hubble constant, such as time-delay cosmography, is highlighted by the recent Hubble tension. It is paramount to thoroughly investigate and rule out systematic biases ...
Solar neutrinos and leptonic spin forces
We quantify the efects of light spin-zero particles with pseudoscalar couplings to leptons and scalar couplings to nucleons on the evolution of solar neutrinos. In this scenario the matter potential sourced by the nucleons ...
Roton instabilities in the superfluid outer core of neutron stars
We study the superfluid dynamics of the outer core of neutron stars by means of a generalized hydrodynamic model made of a neutronic superfluid and a protonic superconductor, coupled by both the dynamic entrainment and the ...
Low-mass enhancement of kaon pairs in B + → D<em> (*)</em> 0 K + K 0 and B 0 → D<em> (*) -</em> K + K 0 decays
Very recently, the Belle II collaboration presented a measurement for the decays + →¯ (*)0 +¯ 0 and 0 → (*)− +¯ 0, with the bulk of observed ( + 0 ) distributions showing low-mass structures in all ...
Performance and first measurements of the MAGIC stellar intensity interferometer
In recent years, a new generation of optical intensity interferometers has emerged, leveraging the existing infrastructure of Imaging Atmospheric Cherenkov Telescopes (IACTs). The MAGIC telescopes host the MAGIC-SII system ...
Status of direct determination of solar neutrino fluxes after Borexino
We determine the solar neutrino fuxes from the global analysis of the most up-to-date terrestrial and solar neutrino data including the fnal results of the three phases of Borexino. The analysis are performed in the framework ...
Observation of New Charmonium or Charmoniumlike States in B+ →D∗±D∓K+ Decays
A study of resonant structures in Bþ → DþD−Kþ and Bþ → D−DþKþ decays is performed, using proton-proton collision data at center-of-mass energies of ffiffi s p ¼ 7, 8, and 13 TeV recorded by the LHCb experiment, corresponding ...
