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Abstract This article introduces a general processing framework to effectively utilize waveform data stored on modern cloud platforms. The focus is hybrid processing schemes for which a local system drives processing. We show that downloading files and doing all processing locally is problematic even when the local system is a high-performance computing (HPC) cluster. Benchmark tests with parallel processing show that approach always creates a bottleneck as the volume of data being handled increases with more processes pulling data. We find a hybrid model for which processing to reduce the volume of data transferred from the cloud servers to the local system can dramatically improve processing time. Tests implemented with the Massively Parallel Analysis System for Seismology (MsPASS) utilizing Amazon Web Service’s (AWS) Lambda service yield throughput comparable to processing day files on a local HPC file system. Given the ongoing migration of seismology data to cloud storage, our results show doing some or all processing on the cloud will be essential for any processing involving large volumes of data. 

We analyze effects of neutron-antineutron transitions in neutron stars, specifically on (i) cooling, (ii) rotation rate, and (iii) for binary pulsars, the increase in the orbital period. We show that these effects are negligibly small. 

Abstract Massive elliptical galaxies harbor large amounts of hot gas (T≳ 10⁶K) in their interstellar medium (ISM) but are typically quiescent in star formation. The jets of active galactic nuclei (AGNs) and Type Ia supernovae (SNe Ia) inject energy into the ISM, which offsets its radiative losses and keeps it hot. SNe Ia deposit their energy locally within the galaxy compared to the larger few ×10 kiloparsec-scale AGN jets. In this study, we perform high-resolution (512³) hydrodynamic simulations of a local (1 kpc³) density-stratified patch of the ISM of massive galaxies. We include radiative cooling and shell-averaged volume heating, as well as randomly exploding SN Ia. We study the effect of different fractions of supernova (SN) heating (with respect to the net cooling rate), different initial ISM density/entropy (which controls the growth timet_tiof the thermal instability), and different degrees of stratification (which affect the freefall timet_ff). We find that SNe Ia drive predominantly compressive turbulence in the ISM with a velocity dispersion ofσ_vup to 40 km s⁻¹and logarithmic density dispersion ofσ_s∼ 0.2–0.4. These fluctuations trigger multiphase condensation in regions of the ISM, where $\min \left(t_{\mathrm{ti}}\right)/t_{\mathrm{ff}}\lesssim 0.6\exp \left(6{\sigma }_s\right)$, in agreement with theoretical expectations that large density fluctuations efficiently trigger multiphase gas formation. Since the SN Ia rate is not self-adjusting, when the net cooling drops below the net heating rate, SNe Ia drive a hot wind which sweeps out most of the mass in our local model. Global simulations are required to assess the ultimate fate of this gas.