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The Einstein Telescope (ET), a wide-band, future third generation gravitational wave detector, is expected to have detection rates of $\sim 10^5 - 10^6$ binary black hole (BBH) detections and $\sim 7 \times 10^4$ binary neutron star (BNS) detections in one year. The coalescence of compact binaries with a total mass of 20 - 100 $M_{\odot}$, typical of BH-BH or BH-NS binaries, will be visible up to redshift $z\approx 20$ and even higher, thus facilitating the understanding of the dark era of the Universe preceding the birth of the first stars. The ET will therefore be a crucial instrument for population studies. We analysed the compact binaries originating in stars from (i) Population (Pop) I+II, (ii) Pop III, and (iii) globular clusters (GCs), with the single ET instrument, using the ET-D design sensitivity for the analysis. We estimated the constraints on the chirp mass, redshift, and merger rate as function of redshift for these classes of compact object binaries. We conclude that the ET as a single instrument is capable of detecting and distinguishing different compact binary populations separated in chirp mass - redshift space. While compact binaries originating in stars from Pop III are clearly distinguishable, owing to the separation in chirp mass - redshift space, the other two populations, Pop I+II, and GCs, can be distinguished with just 500 detections, corresponding to an observation time of $\sim 1$ hr. The mass distribution characteristics of such different compact binary populations can also be estimated with the single ET instrument., Comment: 16 pages, 10 figures, Accepted in Astronomy & Astrophysics

The Einstein Telescope (ET), a future third-generation gravitational wave detector will have detection sensitivity for gravitational wave signals down to 1 Hz. This improved low-frequency sensitivity of the ET will allow the observation of low mass binaries for a longer period of time in the detection band before their merger. Because of an improved sensitivity as compared to current and advanced 2G detectors, the detection rate will also be greatly improved. Given the high detection rate of merging compact binaries with the ET, it will be a useful instrument to conduct population studies. In this paper we present an algorithm to estimate the parameters of the low mass merging compact binary systems such as localization, chirp mass, redshift, mass ratios and total mass of the source which are crucial in order to estimate the capability of the ET to study various compact binary populations. For the compact binary population distributed uniformly in comoving volume we find that with single ET, $\approx 1\%$ of binaries can be localized within 800 square degrees. The values of chirp mass and total mass can be constrained within $\lesssim 5\%$ error, while $z$ and $D_L$ can be estimated with an error of $\lesssim 15\%$ for effective SNR $\gtrsim 50$ using single ET., Comment: 24 pages, 16 figures. Published in Physical Review D

We performed a detailed analysis of the detectability of a wide range of gravitational waves derived from core-collapse supernova simulations using gravitational-wave detector noise scaled to the sensitivity of the upcoming fourth and fifth observing runs of the Advanced LIGO, Advanced Virgo, and KAGRA. We use the coherent WaveBurst algorithm, which was used in the previous observing runs to search for gravitational waves from core-collapse supernovae. As coherent WaveBurst makes minimal assumptions on the morphology of a gravitational-wave signal, it can play an important role in the first detection of gravitational waves from an event in the Milky Way. We predict that signals from neutrino-driven explosions could be detected up to an average distance of 10 kpc, and distances of over 100 kpc can be reached for explosions of rapidly rotating progenitor stars. An estimated minimum signal-to-noise ratio of 10-25 is needed for the signals to be detected. We quantify the accuracy of the waveforms reconstructed with coherent WaveBurst and we determine that the most challenging signals to reconstruct are those produced in long-duration neutrino-driven explosions and models that form black holes a few seconds after the core bounce., Comment: 20 pages, 12 figures, 3 tables

Aims. We estimate the number of pulsars, detectable as continuous gravitational wave sources with the current and future gravitational-wave detectors, assuming a simple phenomenological model of evolving non-axisymmetry of the rotating neutron star. Methods. We employ a numerical model of the Galactic neutron star population, with the properties established by comparison with radio observations of isolated Galactic pulsars. We generate an arbitrarily large synthetic population of neutron stars and evolve their period, magnetic field, and position in space. We use a gravitational wave emission model based on exponentially decaying ellipticity - a non-axisymmetry of the star, with no assumption of the origin of a given ellipticity. We calculate the expected signal in a given detector for a 1 year observations and assume a detection criterion of the signal-to-noise ratio of 11.4 - comparable to a targeted continous wave search. We analyze the population detectable separately in each detector: Advanced LIGO, Advanced Virgo, and the planned Einstein Telescope. In the calculation of the expected signal we neglect signals frequency change due to the source spindown and the Earth motion with respect to the Solar barycentre. Results. With conservative values for the neutron stars evolution: supernova rate once per 100 years, initial ellipticity $\epsilon_{0}$ = 1e-5 with no decay of the ellipticity $\eta$ = $t_\rm{hub}$ = 1e4 Myr, the expected number of detected neutron stars is below one: 0.15 (based on a simulation of 10 M stars) for the Advanced LIGO detector. A broader study of the parameter space ($\epsilon_{0}$ , $\eta$) is presented. With the planned sensitivity for the Einstein Telescope, and assuming the same ellipiticity model, the expected detection number is: 26.4 pulsars during a 1-year long observing run., Comment: 10 pages, submitted to A&A

The Einstein Telescope (ET) is the future third generation gravitational wave detector consisting of three independent interferometers arranged in a triangular configuration, with the sensitivity large enough to be able to detect stellar mass black holes even beyond the redshift of 10. In this paper, we analyze the capabilities of ET as a standalone instrument and not part of a network. We show that the analysis of detection of binary coalescences in the three individual interferometers of the ET allow us to weakly constrain the sky location of the source. We present the analysis that leads to the constraints on the redshift and source frame chirp mass of detected binaries. We show that these values can be estimated with the accuracy comparable to the one expected from networks of gravitational wave interferometers. Thus, we show that the ET as a single instrument is able to break the redshift - chirp mass degeneracy and is therefore a valuable tool to explore properties of populations of merging compact object binaries., Comment: 13 pages, 7 figures. Published in Physical Review D

To predict if developing human embryos are permissive to coronaviruses, we analyzed publicly available single cell RNA-seq datasets of zygotes, 4-cell, 8-cell, morula, inner cell mass, epiblast, primitive endoderm and trophectoderm for the coronavirus receptors (ACE2, BSG, DPP4 and ANPEP), the Spike protein cleavage enzymes (TMPRSS2, CTSL). We also analyzed the presence of host genes involved in viral replication, the endosomal sorting complexes required for transport (ESCRT) and SARS-Cov-2 interactions. The results reveal that ACE2, BSG, DPP4 and ANPEP are expressed in the cells of the zygote, to blastocyst including the trophectodermal lineage. ACE2, TMPRSS, BSG and CTSL are co-transcribed in a proportion of epiblast cells and most cells of the trophectoderm. The embryonic and trophectodermal cells also express genes for proteins ESCRT, viral replication and those that interact with SARS-CoV-2. We identified 1985 genes in epiblast and 1452 genes in the trophectoderm that are enriched in the ACE2 and TMPRSS2 co-expressing cells; 216 genes of these are common in both the cell types. These genes are associated with lipid metabolism, lysosome, peroxisome and oxidative phosphorylation pathways. Together our results suggest that developing human embryos could be permissive to coronavirus entry by both canonical and non-canonical mechanisms and they also express the genes for proteins involved in viral endocytosis and replication. This knowledge will be useful for evidence-based patient management for IVF during the COVID-19 pandemic., Comment: 33 pages, 6 main figures, 3 main table, 2 supplementary figure

Social media generates an enormous amount of data on a daily basis but it is very challenging to effectively utilize the data without annotating or labeling it according to the target application. We investigate the problem of localized flood detection using the social sensing model (Twitter) in order to provide an efficient, reliable and accurate flood text classification model with minimal labeled data. This study is important since it can immensely help in providing the flood-related updates and notifications to the city officials for emergency decision making, rescue operations, and early warnings, etc. We propose to perform the text classification using the inductive transfer learning method i.e pre-trained language model ULMFiT and fine-tune it in order to effectively classify the flood-related feeds in any new location. Finally, we show that using very little new labeled data in the target domain we can successfully build an efficient and high performing model for flood detection and analysis with human-generated facts and observations from Twitter.