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In this paper, pointwise convergence, uniform convergence and compact convergence of sequences of holomorphic functions on an open subset of the complex plane are compared from a linear point of view. In fact, it is proved the existence of large linear algebras consisting, except for zero, of sequences of holomorphic functions tending to zero compactly but not uniformly on the open set or of sequences of holomorphic functions tending pointwisely to zero but not compactly. Also dense linear subspaces in an appropriate Fr\'echet space as well as infinite dimensional Banach spaces of sequences converging to zero in the mentioned modes are shown to exist.

Operating on a surface with high noise rates and requiring susceptible, yet small-scale detectors, the Neutrinos-Angra detector is an excellent platform for technological development and expertise in new detection methods. This report details the primary features of the detector, the electronics involved, and preliminary physics results from the operational phase, particularly the ON-OFF analysis comparing the signals with the reactor in operation (ON) and during the maintenance shut-down (OFF), demonstrating the detector's capability to monitor reactor activity. Additionally, we will briefly discuss the prospects of using a cryogenic calorimeter to detect neutrinos via Coherent Elastic Neutrino-Nucleus Scattering (CEvNS), highlighting potential advancements in neutrino detection technology. Looking ahead, the project promises to play a crucial role in the integration of Latin American scientists and engineers into global scientific collaborations, significantly contributing to the LASF4RI and the broader HECAP strategic framework., Comment: White paper submited to III LASF4RI for HECAP Symposium: Update of the Strategic Plan (26-29/August/2024, ICTP-SAIFR, S\~ao Paulo, Brazil) \url{https://www.ictp-saifr.org/hecap2024/}

It is proved that, if $(P_n)$ is a sequence of polynomials with complex coefficients having unbounded valences and tending to infinity at sufficiently many points, then there is an infinite dimensional closed subspace of entire functions, as well a dense $\mathfrak{c}$-dimensional subspace of entire functions, all of whose nonzero members are hypercyclic for the corresponding sequence $(P_n(D))$ of differential operators. In both cases, the subspace can be chosen so as to contain any prescribed hypercylic function.

The Neutrinos Angra Experiment, a water-based Cherenkov detector, is located at the Angra dos Reis nuclear power plant in Brazil. Designed to detect electron antineutrinos produced in the nuclear reactor, the primary objective of the experiment is to demonstrate the feasibility of monitoring reactor activity using an antineutrino detector. This effort aligns with the International Atomic Energy Agency (IAEA) program to identify potential and novel technologies applicable to nonproliferation safeguards. Operating on the surface presents challenges such as high noise rates, necessitating the development of very sensitive, yet small-scale detectors. These conditions make the Angra experiment an excellent platform for both developing the application and gaining expertise in new technologies and analysis methods. The detector employs a water-based target doped with gadolinium to enhance its sensitivity to antineutrinos. In this work, we describe the main features of the detector and the electronics chain, including front-end and data acquisition components. We detail the data acquisition strategies and the methodologies applied for signal processing and event selection. Preliminary physics results suggest that the detector can reliably monitor reactor operations by detecting the inverse beta decay induced by electron antineutrinos from the reactor.

The optical spectroscopic classification of active galactic nuclei (AGN) into type 1 and type 2 can be understood in the frame of the AGN unification models. However, it remains unclear which physical properties are driving the classification into intermediate sub-types (1.0,1.2,1.5,1.8,1.9). To shed light on this issue, we present an analysis of the effect of extinction and AGN and host galaxy luminosities on sub-type determination for a sample of 159 X-ray selected AGN with a complete and robust optical spectroscopic classification. The sample spans a rest-frame 2 - 10 keV X-ray luminosity range of $10^{42}-10^{46}$ erg s$^{-1}$ and redshifts between 0.05 and 0.75. From the fitting of their UV-to-mid-infrared spectral energy distributions, we extracted the observed AGN over total AGN+galaxy contrast, optical/UV line-of-sight extinction as well as host galaxy and AGN luminosities. The observed contrast exhibits a clear decline with sub-type, distinguishing two main groups: 1.0-5 and 1.8-9/2. This difference is partly driven by an increase in extinction following the same trend. Nevertheless, 50% of 1.9s and 2s lack sufficient extinction to explain the lack of detection of broad emission lines, unveiling the necessity of an additional effect. Our findings show that 1.8-9/2s preferentially live in host galaxies with higher luminosities while displaying similar intrinsic AGN luminosities to 1.0-5s. Consequently, the AGN to host galaxy luminosity ratio diminishes, hindering the detection of the emission of the broad emission lines, resulting in the 1.8-9/2 classification of those with insufficient extinction. Thus, the combination of increasing extinction and decreasing AGN/galaxy luminosity ratio, mainly driven by an increasing host galaxy luminosity, constitutes the main reasons behind the sub-type classification into 1.0-5 and 1.8-9/2., Comment: Accepted to Astronomy & Astrophysics. 15 pages, 21 figures

We report a study on the static and dynamic properties of several liquid 5$d$ transition metals at thermodynamic conditions near their respective melting points. This is performed by resorting to ab initio molecular dynamics simulations in the framework of the density functional theory. Results are presented for the static structure factors and pair distribution functions; moreover, the local short range order in the liquid metal is also analized. As for the dynamical properties, both single-particle and collective properties are evaluated. The dynamical structure shows the propagating density fluctuations, and the respective dispersion relation is obtained. Results are also obtained for the longitudinal and transverse current spectral functions along with the associated dispersion of collective excitations. For some metals, we found the existence of two branches of transverse collective excitations in the region around the main peak of the structure factor. Finally, several transport coefficients are also calculated., Comment: 20 pages, 19 figures, 5 tables

This article describes the setup and performance of the near and far detectors in the Double Chooz experiment. The electron antineutrinos of the Chooz nuclear power plant were measured in two identically designed detectors with different average baselines of about 400 m and 1050 m from the two reactor cores. Over many years of data taking the neutrino signals were extracted from interactions in the detectors with the goal of measuring a fundamental parameter in the context of neutrino oscillation, the mixing angle {\theta}13. The central part of the Double Chooz detectors was a main detector comprising four cylindrical volumes filled with organic liquids. From the inside towards the outside there were volumes containing gadolinium-loaded scintillator, gadolinium-free scintillator, a buffer oil and, optically separated, another liquid scintillator acting as veto system. Above this main detector an additional outer veto system using plastic scintillator strips was installed. The technologies developed in Double Chooz were inspiration for several other antineutrino detectors in the field. The detector design allowed implementation of efficient background rejection techniques including use of pulse shape information provided by the data acquisition system. The Double Chooz detectors featured remarkable stability, in particular for the detected photons, as well as high radiopurity of the detector components., Comment: 49 pages, 29 figures

We study the thermodynamic properties of a relativistic magnetized neutral vector boson gas at any temperature. By comparing the results with the low temperature and the non relativistic descriptions of this gas, we found that the fully relativistic case can be separated in two regimes according to temperature. For low temperatures, magnetic field effects dominate and the system shows a spontaneous magnetization, its pressure splits in two components and, eventually, a transversal magnetic collapse might occur. In the high temperature region, the gas behavior is led by pair production. The presence of antiparticles preserves the isotropy in the pressure, and increases the magnetization and the total pressure of the system by several orders. Astrophysical implications of those behaviors are discussed., Comment: 26 pages, 7 figures

We present geometric and dynamical modeling of the broad line region for the multi-wavelength reverberation mapping campaign focused on NGC 5548 in 2014. The dataset includes photometric and spectroscopic monitoring in the optical and ultraviolet, covering the H$\beta$, C IV, and Ly$\alpha$ broad emission lines. We find an extended disk-like H$\beta$ BLR with a mixture of near-circular and outflowing gas trajectories, while the C IV and Ly$\alpha$ BLRs are much less extended and resemble shell-like structures. There is clear radial structure in the BLR, with C IV and Ly$\alpha$ emission arising at smaller radii than the H$\beta$ emission. Using the three lines, we make three independent black hole mass measurements, all of which are consistent. Combining these results gives a joint inference of $\log_{10}(M_{\rm BH}/M_\odot) = 7.64^{+0.21}_{-0.18}$. We examine the effect of using the $V$ band instead of the UV continuum light curve on the results and find a size difference that is consistent with the measured UV-optical time lag, but the other structural and kinematic parameters remain unchanged, suggesting that the $V$ band is a suitable proxy for the ionizing continuum when exploring the BLR structure and kinematics. Finally, we compare the H$\beta$ results to similar models of data obtained in 2008 when the AGN was at a lower luminosity state. We find that the size of the emitting region increased during this time period, but the geometry and black hole mass remain unchanged, which confirms that the BLR kinematics suitably gauge the gravitational field of the central black hole., Comment: 26 pages, 19 figures, 1 table, accepted for publication in ApJ

We present a search for signatures of neutrino mixing of electron anti-neutrinos with additional hypothetical sterile neutrino flavors using the Double Chooz experiment. The search is based on data from 5 years of operation of Double Chooz, including 2 years in the two-detector configuration. The analysis is based on a profile likelihood, i.e.\ comparing the data to the model prediction of disappearance in a data-to-data comparison of the two respective detectors. The analysis is optimized for a model of three active and one sterile neutrino. It is sensitive in the typical mass range $5 \cdot 10^{-3} $ eV$^2 \lesssim \Delta m^2_{41} \lesssim 3\cdot 10^{-1} $ eV$^2$ for mixing angles down to $\sin^2 2\theta_{14} \gtrsim 0.02$. No significant disappearance additionally to the conventional disappearance related to $\theta_{13} $ is observed and correspondingly exclusion bounds on the sterile mixing parameter $\theta_{14} $ as function of $ \Delta m^2_{41} $ are obtained., Comment: accepted for publication by EPJC

In this expository article, we give several examples showing how drastically different can be the behavior of operators acting on finite versus infinite dimensional Hilbert spaces. This essay is written as in such a friendly-reader to show that the situation in the infinite dimensional setting is trickier than the finite one., Comment: 11 pages, some materials are added

A $\theta_{13}$ oscillation analysis based on the observed antineutrino rates at the Double Chooz far and near detectors for different reactor power conditions is presented. This approach provides a so far unique simultaneous determination of $\theta_{13}$ and the total background rates without relying on any assumptions on the specific background contributions. The analysis comprises 865 days of data collected in both detectors with at least one reactor in operation. The oscillation results are enhanced by the use of 24.06 days (12.74 days) of reactor-off data in the far (near) detector. The analysis considers the \nue interactions up to a visible energy of 8.5 MeV, using the events at higher energies to build a cosmogenic background model considering fast-neutrons interactions and $^{9}$Li decays. The background-model-independent determination of the mixing angle yields sin$^2(2\theta_{13})=0.094\pm0.017$, being the best-fit total background rates fully consistent with the cosmogenic background model. A second oscillation analysis is also performed constraining the total background rates to the cosmogenic background estimates. While the central value is not significantly modified due to the consistency between the reactor-off data and the background estimates, the addition of the background model reduces the uncertainty on $\theta_{13}$ to 0.015. Along with the oscillation results, the normalization of the anti-neutrino rate is measured with a precision of 0.86\%, reducing the 1.43\% uncertainty associated to the expectation.

We report an ab initio molecular dynamics simulation study of several static and dynamic properties of the liquid 3d transition metals. The calculated static structure factors show qualitative agreement with the available experimental data, and its second peak displays an asymmetric shape which suggests a significant local icosahedral short-range order. The dynamical structure reveals propagating density fluctuations whose dispersion relation has been evaluated; moreover, its long wavelength limit is compatible with their respective experimental sound velocity. Results are reported for the longitudinal and transverse current spectral functions as well as for the respective dispersion relations. We also analyze the possible appearance of transverse-like low-energy excitations in the calculated dynamic structure factors. Several transport coefficients have been evaluated and compared with the available experimental data., Comment: 12 pages, 10 figures, 3 tables

We report velocity-delay maps for prominent broad emission lines, Ly_alpha, CIV, HeII and H_beta, in the spectrum of NGC5548. The emission-line responses inhabit the interior of a virial envelope. The velocity-delay maps reveal stratified ionization structure. The HeII response inside 5-10 light-days has a broad single-peaked velocity profile. The Ly_alpha, CIV, and H_beta responses peak inside 10 light-days, extend outside 20 light-days, and exhibit a velocity profile with two peaks separated by 5000 km/s in the 10 to 20 light-day delay range. The velocity-delay maps show that the M-shaped lag vs velocity structure found in previous cross-correlation analysis is the signature of a Keplerian disk with a well-defined outer edge at R=20 light-days. The outer wings of the M arise from the virial envelope, and the U-shaped interior of the M is the lower half of an ellipse in the velocity-delay plane. The far-side response is weaker than that from the near side, so that we see clearly the lower half, but only faintly the upper half, of the velocity--delay ellipse. The delay tau=(R/c)(1-sin(i))=5 light-days at line center is from the near edge of the inclined ring, giving the inclination i=45 deg. A black hole mass of M=7x10^7 Msun is consistent with the velocity-delay structure. A barber-pole pattern with stripes moving from red to blue across the CIV and possibly Ly_alpha line profiles suggests the presence of azimuthal structure rotating around the far side of the broad-line region and may be the signature of precession or orbital motion of structures in the inner disk. Further HST observations of NGC 5548 over a multi-year timespan but with a cadence of perhaps 10 days rather than 1 day could help to clarify the nature of this new AGN phenomenon., Comment: 19 pages, 9 figures, ApJ in press

The Neutrinos Angra Experiment is a water-based Cherenkov detector located in the Angra dos Reis nuclear power plant. The experiment has completed a major step by finishing the commissioning of the detector and the data acquisition system at the experimental site. The experiment was designed to detect the electron antineutrinos produced by the nuclear reactor with the main purpose to demonstrate the feasibility of monitoring the reactor activity using an antineutrino detector. This effort is within the context of the International Atomic Energy Agency (IAEA) program to identify potential and novel technologies that can be applied for non-proliferation safeguards. Challenges, such as operating at the surface, therefore with huge noise rates, and the need to build very sensitive but small-scale detectors, make the Angra experiment an excellent platform for developing the application itself, as well as acquiring expertise in new technologies and analysis methods. In this report, we describe the main detector features and the electronics chain (front-end and data acquisition). We also report preliminary physics results obtained from the commissioning phase data. Finally, we address conclusions regarding the future perspectives to keep this program active, due to its importance in the insertion of Latin-American scientists and engineers in a world-scale cutting edge scientific program., Comment: arXiv admin note: substantial text overlap with arXiv:1812.11604