Interacting viscous ghost tachyon, K-essence and dilaton scalar field models of dark energy

We study the correspondence between the interacting viscous ghost dark energy model with the tachyon, K-essence and dilaton scalar field models in the framework of Einstein gravity. We consider a spatially non-flat FRW universe filled with interacting viscous ghost dark energy and dark matter. We reconstruct both the dynamics and potential of these scalar field models according to the evolutionary behavior of the interacting viscous ghost dark energy model, which can describe the accelerated expansion of the universe. Our numerical results show that the interaction and viscosity have opposite effects on the evolutionary properties of the ghost scalar filed models.Comment: 16 pages, 17 figure

Genotypes performance in relation to drought tolerance in barley using multi-environment trials

ArticleThe selection of stable and superior genotypes, with the aim of improving grain yield in breeding programs, requires the evaluation of genotypes under different environments. In this study, the yields of 10 barley genotypes were evaluated in eight different environments using a graphical method (GGE biplot). These experiments were conducted from 2011 to 2015. There were irrigated and rain-fed conditions, as a randomized complete block design (RCBD) with three replications. Results indicated that the two components of PC1 and PC2 explained 62.9% and 14.9% of the total variation observed in the yield, respectively. Genotypes with a positive value for PC1 (i.e., PC1 > 0) had the adaptable and the highest performance, whereas genotypes with a negative value for the first component (i.e., PC1 < 0) were non-adaptable and had the lowest performance. Likewise, among the genotypes, some had their second component scores near zero, and they exhibited the greatest stability compared to other genotypes. Specifically, genotype 3 had the highest grain yield and stability, while genotypes 2 and 8 showed relatively high yields

Unique probe of dark matter in the core of M87 with the Event Horizon Telescope

We demonstrate the unprecedented capabilities of the Event Horizon Telescope (EHT) to image the innermost dark matter profile in the vicinity of the supermassive black hole at the center of the M87 radio galaxy. We present the first model of the synchrotron emission induced by dark matter annihilations from a spiky profile in the close vicinity of a supermassive black hole, accounting for strong gravitational lensing effects. Our results show that the EHT should readily resolve dark matter spikes if present. Moreover, the photon ring surrounding the silhouette of the black hole is clearly visible in the spike emission, which introduces observable small-scale structure into the signal. We find that the dark matter-induced emission provides an adequate fit to the existing EHT data, implying that in addition to the jet, a dark matter spike may account for a sizable portion of the millimeter emission from the innermost (subparsec) region of M87. Regardless, our results show that the EHT can probe very weakly annihilating dark matter. Current EHT observations already constrain very small cross sections, typically down to a few 10−31 cm3 s−1 for a 10 GeV candidate, close to characteristic values for p-wave-suppressed annihilation. Future EHT observations will further improve constraints on the DM scenario

Restoring New Agegraphic Dark Energy in RS II Braneworld

Motivated by recent works [1,2], we investigate new agegraphic model of dark energy in the framework of RS II braneworld. We also include the case of variable gravitational constant in our model. Furthermore, we establish correspondence between the new agegraphic dark energy with other dark energy candidates based on scalar fields.Comment: 13 pages, accepted for publication in IJT