On probing turbulence in core-collapse supernovae in upcoming neutrino detectors

Neutrino propagation through a turbulent medium can be highly non-adiabatic leading to distinct signatures in the survival probabilities. A core-collapse supernova can be host to a number of hydrodynamic instabilities which occur behind the shockfront. Such instabilities between the forward shock and a possible reverse shock can lead to cascades introducing turbulence in the associated matter profile, which can imprint itself in the neutrino signal. In this work, we consider realistic matter profiles and seed in the turbulence using a randomization scheme to study its effects on neutrino propagation in an effective two-flavor framework. In particular, we find that the double-dip feature, originally predicted in the neutrino spectra associated with forward and reverse shocks, can be completely washed away in the presence of turbulence, leading to total flavor depolarization. We also study the sensitivity of upcoming neutrino detectors - DUNE and Hyper-Kamiokande- to the power spectrum of turbulence to check for deviations from the usual Kolmogorov ($5/3$) inverse power law. We find that while these experiments can effectively constrain the parameter space for the amplitude of the turbulence power spectra, they will only be mildly sensitive to the spectral index.Comment: 18 pages, 8 figure

Resonance structures in kink-antikink scattering in a quantum vacuum

We investigate kink-antikink scattering in the $\lambda \phi^4$ model in the presence of an additional scalar field, $\psi$, that is in its quantum vacuum and interacts with $\phi$ via a $\xi \phi^2\psi^2$ term where $\xi$ is the coupling. The final state of such a scattering is either a bound state with eventual annihilation or a reflection of the kink-antikink pair. Without the $\psi$ field, the outcome is known to depend fractally on the initial velocity of the kink-antikink pair. In the quantum vacuum of the $\psi$ field, the fractal dependence gets modified and disappears above a critical interaction strength, $\xi \approx 0.1$.Comment: 11 pages, 9 figures, published versio

Multi-messenger signatures of delayed choked jets in tidal disruption events

Recent radio observations and coincident neutrino detections suggest that some tidal disruption events (TDEs) exhibit late-time activities, relative to the optical emission peak, and these may be due to delayed outflows launched from the central supermassive black hole. We investigate the possibility that jets launched with a time delay of days to months, interact with a debris that may expand outwards. We discuss the effects of the time delay and expansion velocity on the outcomes of jet breakout and collimation. We find that a jet with an isotropic-equivalent luminosity of $\lesssim 5 \times 10^{45}\,{\rm erg/s}$ is likely to be choked for a delay time of $\sim 3$ months. We also study the observational signatures of such delayed choked jets. The jet-debris interaction preceding the breakout would lead to particle acceleration and the resulting synchrotron emission can be detected by current and near-future radio, optical and X-ray telescopes, and the expanding jet-driven debris could explain late-time radio emission. We discuss high-energy neutrino production in delayed choked jets, and the time delay can significantly alleviate the difficulty of the hidden jet scenario in explaining neutrino coincidences.Comment: 14 pages, 7 figure

A New Blind DOA Estimation Using Two Uniform Linear Array for Low Side Lobe Adaptive Array

312-314Suitably designed Adaptive algorithm can collect the main signals’ multipath and add them constructively with main signal with very low side lobe level in all other directions, hence eliminating the jamming signal from other directions. A new technique for DOA estimation of signals impinging on Two Uniform Linear Array (ULA) offset with each other by a known angle also has been proposed for further analysis and discussions

Gravitational wave triggered searches for high-energy neutrinos from binary neutron star mergers: prospects for next generation detectors

The next generation gravitational wave (GW) detectors - Einstein Telescope (ET) and Cosmic Explorer (CE), will have distance horizons up to $\mathcal{O}(10)$ Gpc for detecting binary neutron star (BNS) mergers. This will make them ideal for triggering high-energy neutrino searches from BNS mergers at the next generation neutrino detectors, such as IceCube-Gen2. We calculate the distance limits as a function of the time window of neutrino analysis, up to which meaningful triggers from the GW detectors can be used to minimize backgrounds and collect a good sample of high-energy neutrino events at the neutrino detectors, using the sky localization capabilities of the GW detectors. We then discuss the prospects of the next generation detectors to work in synergy to facilitate coincident neutrino detections or to constrain the parameter space in the case of non-detection of neutrinos. We show that good localization of GW events, which can be achieved by multiple third generation GW detectors, is necessary to detect a GW-associated neutrino event or put a meaningful constraint ($\sim 3\sigma$ confidence level) on neutrino emission models. Such a model independent analysis can also help constrain physical models and hence provide insights into neutrino production mechanisms in binary neutron star mergers.Comment: 14 pages, 4 figure

Is autophagy associated with diabetes mellitus and its complications?

Diabetes mellitus (DM) is an endocrine disorder. In coming decades it will be one of the leading causes of death globally. The key factors in the pathogenesis of diabetes are cellular injuries and disorders of energy metabolism leading to severe diabetic complications. Recent studies have confirmed that autophagy plays a pivotal role in diabetes and its complications. It has been observed that autophagy regulates the normal function of pancreatic β cells and insulin-target tissues, such as skeletal muscle, liver, and adipose tissue. This review will summarize the regulation of autophagy in diabetes and its complications, and explore how this process would emerge as a potential therapeutic target for diabetes treatment