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

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Not AvailableA field experiment was carried out during the summer season of the year 2013 to study the “Influence of spacing and scheduling of irrigation on growth, yield and yield attributes of summer green gram (Vigna radiata L.)”. The plant height at harvest significantly influenced and recorded highest under treatment I3 (1.0 IW:CPE ratio). Number of branches plant-1 was significantly the highest, while number of pods plant-1, pod length, number of seeds pod-1, seed yield (1107 kg ha-1) and stover yield (1970) were observed significantly higher under the irrigation treatment of I3 (1.0 IW:CPE ratio) followed by I2 (0.8 IW:CPE ratio). In case of spacing, the number of branches plant-1, number of pods plant-1, number of seeds pod-1 were significantly higher under treatment S1 (30 x 10 cm) followed by treatment S10 (22.5 x 10 cm). An interaction effect between irrigation schedule and spacing levels on number of pod plant-1 and seed yield were found to be significantly higher under treatment combination I3S1 (1.0 IW/CPE ratio with 30 x 10 cm spacing) followed by treatment combination I2S1 (0.8 IW/CPE ratio with 30 x 10 cm spacing). Treatment combination I3S1 (1.0 IW:CPE ratio with 30 x 10 cm) registered highest net realization of Rs. 49118 ha-1 with BCR value of 1:3.14 followed by treatment combination I2S1 (0.8 IW:CPE ratio with 30 x 10 cm)Not Availabl

Not Available

Not AvailableA field experiment was carried out during the summer season of the year 2013 to study the “Influence of spacing and scheduling of irrigation on growth, yield and yield attributes of summer green gram (Vigna radiata L.)”. The plant height at harvest significantly influenced and recorded highest under treatment I3 (1.0 IW:CPE ratio). Number of branches plant-1 was significantly the highest, while number of pods plant-1, pod length, number of seeds pod-1, seed yield (1107 kg ha-1) and stover yield (1970) were observed significantly higher under the irrigation treatment of I3 (1.0 IW:CPE ratio) followed by I2 (0.8 IW:CPE ratio). In case of spacing, the number of branches plant-1, number of pods plant-1, number of seeds pod-1 were significantly higher under treatment S1 (30 x 10 cm) followed by treatment S10 (22.5 x 10 cm). An interaction effect between irrigation schedule and spacing levels on number of pod plant-1 and seed yield were found to be significantly higher under treatment combination I3S1 (1.0 IW/CPE ratio with 30 x 10 cm spacing) followed by treatment combination I2S1 (0.8 IW/CPE ratio with 30 x 10 cm spacing). Treatment combination I3S1 (1.0 IW:CPE ratio with 30 x 10 cm) registered highest net realization of Rs. 49118 ha-1 with BCR value of 1:3.14 followed by treatment combination I2S1 (0.8 IW:CPE ratio with 30 x 10 cm)Not Availabl

Experimental studies of the base flow from the nozzles with sudden expansion with micro jets

A method for evaluating the performance of micro jets, in a flow behind a highly expanded nozzle is presented. In the process, the pressure distribution of the flow behind the nozzle outlet is calculated for a defined range of Mach numbers. The outcome shows the existence of oblique shock, Mach waves, and expansion fan in the investigation depending upon the expansion level of the shear layer at the nozzle lip. The height of the backward facing step is 2.5. The range of NPRs chosen for this case is within 3 and 11.Since very small jets are used as active control method, four jets of one millimeter hole diameter are installed for flow control. It is observed that the control effectiveness is quite good for the entire range of L/D at around Mach 2.0. For L/D ranging from 10 to 2, the decrements in the suction at the base exhibits thirty per cent increase in base pressure with micro jets. The final argument is that efficacy of the flow regulation is case sensitive and to arrive at the optimum flow variable lot of runs are needed to draw the conclusions. Also, the efficacy of very small jets is improved for suitable pressure gradient. For over expanded jets the dynamic effectiveness is minimum. The nature of flow in the abruptly expanded duct, in the presence and absence of the flow manipulator is unaltered and hence, remains identical for most of the cases

Effect of level of expansion and inertia level in a suddenly expanded flow

An experimental study has been carried out to assess the effectiveness of the active control in the form of micro jets to control the base pressure in a suddenly expanded axi-symmetric duct. Four micro jets of 1mm orifice diameter located at 90 intervals along a pitch circle diameter of 1.3 times the nozzle outlet diameter in the base region are employed as active controls. The Mach numbers of the present study are 2.5 and 3.0. The jets are expanded suddenly into an axi-symmetric circular tube with four cross-sectional area 2.56, 3.24, 4.84 and 6.25 times that of nozzle exit area. The Length to Diameter ratio of the suddenly expanded duct is varied from 10 to 1 and experiments are conducted for Nozzle Pressure Ratio (NPR) from 3 to 11. Since the jets remain over expanded for all the NPRs of the present study, even though, with increase in the NPR, the level of over expansion will decrease. It is well known that for over expanded nozzles an oblique shock will be formed at the nozzle lip, which in turn will result in the increase of the base pressure once it passes through the shock wave. From the results it is observed that for the NPRs 3 and 5 there is no appreciable gain in the base pressure, and hence, control employed in the form of micro jets is not effective, however, at NPR 7, 9, and 11 there is remarkable change in the base pressure values. This clearly indicates that the level of expansion plays a significant role to decide on the value of the base pressure and the control effectiveness of the micro jets. It is found that the micro jets can serve as an effective controller of base pressure in a suddenly expanded duct. The micro jets do not adversely influence the wall pressure flow field in the enlarge duct

Towards a predictive framework for biocrust mediation of plant performance: A meta-analysis

Understanding the importance of biotic interactions in driving the distribution and abundance of species is a central goal of plant ecology. Early vascular plants likely colonized land occupied by biocrusts — photoautotrophic, surface-dwelling soil communities comprised of cyanobacteria, bryophytes, lichens and fungi — suggesting biotic interactions between biocrusts and plants have been at play for some 2,000 million years. Today, biocrusts coexist with plants in dryland ecosystems worldwide, and have been shown to both facilitate or inhibit plant species performance depending on ecological context. Yet, the factors that drive the direction and magnitude of these effects remain largely unknown. We conducted a meta-analysis of plant responses to biocrusts using a global dataset encompassing 1,004 studies from six continents. Meta-analysis revealed there is no simple positive or negative effect of biocrusts on plants. Rather, plant responses differ by biocrust composition and plant species traits and vary across plant ontogeny. Moss-dominated biocrusts facilitated, while lichen-dominated biocrusts inhibited overall plant performance. Plant responses also varied among plant functional groups: C grasses received greater benefits from biocrusts compared to C grasses, and plants without N-fixing symbionts responded more positively to biocrusts than plants with N-fixing symbionts. Biocrusts decreased germination but facilitated growth of non-native plant species. Synthesis. Results suggest that interspecific variation in plant responses to biocrusts, contingent on biocrust type, plant traits, and ontogeny can have strong impacts on plant species performance. These findings have important implications for understanding biocrust contributions to plant productivity and community assembly processes in ecosystems worldwide.USGS Ecosystem and Land Change Sciences Program; DePaul University College of Science and Health; National Science Foundation, Grant/Award Number: DEB‐1844531; U.S. Geological Survey; University of Colorado Boulder, Grant/ Award Number: DGE‐1144083; Consejo Nacional de Ciencia y Tecnología, Grant/ Award Number: SEP‐CONACYT 25138