Poverty, Income Inequalities and Migration in the Global South

In this chapter, we critically engage with the existing literature to explore how the condition of countries of origin, the situation in countries of destination and the role of remittances relate to the key analytical instruments of poverty and income inequalities. We analyse the ways in which income inequalities contribute to patterns of migration; the mechanisms by which resources are transferred back to places of origin and their impacts on poverty and income inequalities; and the impact of migration on patterns of inequalities in places where people move. We discuss whether migration can play a role in reducing income inequality, by helping increase incomes and contribute to poverty alleviation, or whether it is a very selective phenomenon that tends to exacerbate inequalities. Global South and South–South migration are included in the analysis, albeit through a critical approach, that highlights the need to consider the historical dimensions involved in their creation, the political construction of these categories and the limitations embedded in their theoretical application

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Poverty, Income Inequalities and Migration in the Global South

In this chapter, we critically engage with the existing literature to explore how the condition of countries of origin, the situation in countries of destination and the role of remittances relate to the key analytical instruments of poverty and income inequalities. We analyse the ways in which income inequalities contribute to patterns of migration; the mechanisms by which resources are transferred back to places of origin and their impacts on poverty and income inequalities; and the impact of migration on patterns of inequalities in places where people move. We discuss whether migration can play a role in reducing income inequality, by helping increase incomes and contribute to poverty alleviation, or whether it is a very selective phenomenon that tends to exacerbate inequalities. Global South and South–South migration are included in the analysis, albeit through a critical approach, that highlights the need to consider the historical dimensions involved in their creation, the political construction of these categories and the limitations embedded in their theoretical application

Multimessenger Analysis Strategy for Core-Collapse Supernova Search: Gravitational Waves and Low-energy Neutrinos

Core-collapse supernovae are fascinating astrophysical objects for multimessenger studies. Gravitational waves (GWs) are expected to play a role in the supernova explosion mechanism, but their modelling is also challenging due to the stochastic nature of the dynamics and the vast possible progenitors, and moreover, the GW detection from these objects is still elusive with the already advanced detectors. Low-energy neutrinos will be emitted enormously during the core-collapse explosion and can help for the gravitational wave counterpart search. In this work we develop a multi-messenger strategy to search for such astrophysical objects by exploiting a global network of both low-energy neutrino and gravitational wave detectors. First, we discuss how to improve the detection potential of the neutrino sub-network by exploiting the temporal behaviour of a neutrino burst from a core-collapse supernova. We show that with the proposed approach neutrino detectors can gain at least $10\%$ of detection efficiency at the distance where their efficiency drops. Then, we combine the information provided by GW and neutrino in a multimessenger strategy. In particular, we obtain an increase of the probability to detect the GW signal from a CCSN at $60$ kpc from zero when using only GW analysis to $\sim 33\%$ with our combined GW-$\nu$ approach. Keywords: multimessenger, supernova, core-collapse, low-energy neutrino, gravitational wave.Comment: 14 pages, 15 figure

Borders, Migration and Globalization. An Interdisciplinary Perspective

Nowadays the reality of migrations defines the policies both of host and origin countries, invades the everyday life of all of us, dominates the pubòic language, builds new borders, and destroys others. The borders are a multifaceted concept that adapts to different disciplinary languages , that includes and covers unlike realities and for this reason represents a useful gimmick to deal with a theme, migrations, that in turn needs numerous perspectives of analysis to be adequately faced. borders can have the concreteness of geographical, political and bureaucratic barriers, or they may be methaphorical barrierrs: identity, prejudices, culture. through territories and consciences, they mark a space that includes and excludes at the same time