Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3b

We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC-2020 March 27 17:00 UTC). We conduct two independent searches: A generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate. © 2022. The Author(s). Published by the American Astronomical Society

Open data from the third observing run of LIGO, Virgo, KAGRA, and GEO

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages

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

Despite the growing number of binary black hole coalescences confidently 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 the 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 have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame mass M > 70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave 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 a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 < e ≤ 0.3 at 16.9 Gpc−3 yr−1 at the 90% confidence level

Is it really a win win situation: Henna (Lawsonia inermis L.) farming for rural sustainability and economic security in arid zone

Henna (Lawsonia inermis L.), is a perennial shrub dominating the agro-ecosystem of Pali district of Rajasthan, India, which is priced for its leaves which have natural dying properties. From ancient times, Henna has been employed as a cosmetic dye for hair, skin and nails and it has acquired a particular significance in Islamic culture. It is dryland shrub which can tolerate extreme dry and high temperature conditions and survives well on problematic soils with high pH and saline water where other crops cannot be grown. The development of Henna cultivation and processing in Pali, Rajasthan, is a blend of indigenous knowledge and people's innovations. Presently Henna cultivation in the region is under 40,000 hectares which is the largest area under this crop at single location and it is purely rainfed with no use of fertilizers or pesticides. In this crop generally, no fertilizers and plant protection measures are used and a single leaf cutting is taken every year under the rainfed conditions and two cuttings where water is available. Under rainfed conditions for a dense planting the dried leaf yield in the first year is about 250 kg ha-1 while over the second, third and fourth years the yield normally ranges from 500 to 2,500 kg ha-1. The crop starts generating returns from its second year onwards, which continues for 20 years while incurring only maintenance costs in the form of hoeing, weeding and harvesting. By following these measures, on average they produce 15-20 quintal dry Henna leaves ha-1 from their barren fields. The financial analysis indicated that Henna farming due to its high quality at Pali is a profitable and attractive option for farmers livelihoods. Sustainable income from Henna benefits the farmers of the district as it can tolerate high salinity, drought and incidences of pest and diseases

Understanding agroecological domains: The key to a successful participatory plant breeding program

Farmers have an intricate knowledge of their agro ecological domains. The empirical evidences from Kachorwa (terai) and Begans (mid-hill) sites in Nepal suggest that farmers distinguish domains for rice primarily on the basis of moisture and fertility. Farmers also differentiate the number, relative size, and specific characteristics of each domain within a given geographic area. Similarly, they allocate Individual varieties landraces to each domain, indicating that the competition between varieties landraces occurs within the domain and that transgression of domain was rather limited. These deductions need to be verified at a wider level. A fuller understanding by researchers of specific agro ecological domains is a prerequisite for them to contribute substantially in planning and executing effective participatory plant breeding (PPB) programs. Only with a sound knowledge of agro ecological domains and the varietal distribution within domains can a program on diversity deployment and biodiversity conservation be effectively implemented. Likewise, justifying Ihe cost-effectiveness of PPB, targeting research extension activities, and measuring the contribution of PPB to food security demands a detailed understanding of agro ecological domains. Simple and practical ways to illicit information on agro ecological domains and associated varieties landraces through farmer' group discussion al the village level have been suggested as a pre-project activity for PPB, which could enhance the success of PPB programs