Radio burst from a stellar coronal mass ejection

Coronal mass ejections (CMEs) are massive expulsions of magnetized plasma from a star and are the largest contributors to space weather in the Solar System1,2. CMEs play an important role in planetary atmospheric erosion, especially for planets that are close to their host star3, 4–5. However, this conclusion remains controversial as there has not been an unambiguous detection of a CME from a star outside our Sun. Previous stellar CME studies have only inferred the presence of a CME through the detection of other types of stellar eruptive event6, 7, 8–9. A signature of a fast CME is a type II radio burst10,11, which is emitted from the shock wave produced as the CME travels through the stellar corona into interplanetary space. Here we report an analogue to a type II burst from the early M dwarf StKM 1-1262. The burst exhibits identical frequency, time and polarization properties to fundamental plasma emission from a solar type II burst. We demonstrate that the rate of these events with similar radio luminosity from M dwarfs is 0.84−0.69+1.94×10−3 per day per star. Our detection implies that we are no longer restricted to extrapolating the solar CME kinematics and rates to other stars, allowing us to establish observational limits on the impact of CMEs on exoplanets.</p

Strong correlation behavior and strong coupling superconductivity in (Ti_1/4Hf_1/4Nb_1/4Ta_1/4)_1−xNi_x with the rich magnetic element Ni

Searching for new superconductors, especially unconventional superconductors, has been studied extensively for decades but remains one of the major outstanding challenges in condensed matter physics. Medium/high-entropy alloys (MEAs-HEAs) are new fertile soils of unconventional superconductors and generate widespread interest and questions on the existence of superconductivity in highly disordered materials. Here, we report on the effect of Ni-doped on the crystal structure and superconductivity properties of strongly coupled TiHfNbTa MEA. X-ray diffraction results indicate that the maximum solid solution of (Ti1/4Hf1/4Nb1/4Ta1/4)1−xNix is about 7.7%. Resistivity, magnetic susceptibility, and specific heat measurements demonstrated that (Ti1/4Hf1/4Nb1/4Ta1/4)1−xNix HEAs are all bulk type-II superconductors and follow the trend of the increase of Tc with the increase of Ni-doped contents. The specific heat jump (ΔCel/γ T c mid ) of all (Ti1/4Hf1/4Nb1/4Ta1/4)1−xNix are much larger than the BCS value of 1.43, suggesting all these HEAs are strongly coupled superconductors. Additionally, large Kadawaki-Woods ratio values suggest that there is a strong electron correlation effect in this system. The (Ti1/4Hf1/4Nb1/4Ta1/4)1−xNix HEA system is a new ideal material platform for the study of strong correlation behavior and strongly coupled superconductivity, which provides an insight into the physics of high-temperature superconductors or other unconventional superconductors.</p

Estimation of and y distortions in the cosmic microwave background with COBE/FIRAS data

This paper presents a novel approach to estimate the and y-distortions in the Cosmic Microwave Background (CMB) using the COBE/FIRAS data. The analysis draws from the concept of blackbody radiation inversion (BRI), a mathematical technique typically used to determine the temperature distribution from a radiated power spectrum. We study the deviations from the ideal blackbody spectrum or the spectral distortions by incorporating first a non-zero chemical potential via the Bose-Einstein distribution and then also adding the Compton parameter y while keeping the monopole temperature constant. We infer the results as probability distribution functions on these distortions. Finally, we derive and at a confidence interval. Here we show how the BRI method performs in a test-case scenario, illustrating its potential for extracting spectral distortion parameters in CMB.</p

De verjaringsregel van art. 3:310 lid 4 BW:Enkele bezwaren uitgelicht mede naar aanleiding van rechtspraak over bestuurdersaansprakelijkheid

Bij schade die is veroorzaakt door strafbare feiten wordt op grond van art. 3:310 lid 4 BW de civiele verjaringstermijn van rechtsvorderingen tot schadevergoeding verlengd tot het moment dat het recht tot strafvordering verjaart. De auteurs bespreken hoe deze bepaling wordt toegepast in de praktijk en geven eenkritische analyse

Introduction:Amsterdam in Diaries and Life Writing

This introduction outlines the central theme of the volume: the representation of Amsterdam in diaries and other modes and forms of life writing. It situates this theme within the broader context of diary studies and urban history and addresses the crossovers between these fields of study. With the aim to grasp the interplay between self and city in urban lives, it explores various approaches to examining how the city has influenced and shaped individual identities, as well as how self-representations have, in turn, contributed to the shaping of the city’s imagery and urban fabric. The structure of the volume is explained through an overview of its five thematic sections: “Coming of Age,” “Belonging,” “Routes and Routines,” “Digital Lives” and a “Creative Section.