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1. Characterizing Cortex-Wide Dynamics with Wide-Field Calcium Imaging

   https://doi.org/10.1523/JNEUROSCI.3003-20.2021  

   Ren, Chi; Komiyama, Takaki (May 2021, The Journal of Neuroscience)
2. Characterizing Cortex-Wide Dynamics with Wide-Field Calcium Imaging

   https://doi.org/https://doi.org/10.1523/JNEUROSCI.3003-20.2021  

   Ren, C. and (May 2021, The journal of neuroscience)

   null (Ed.)
3. Thermal management and packaging of wide and ultra-wide bandgap power devices: a review and perspective

   https://doi.org/10.1088/1361-6463/acb4ff  

   Qin, Yuan; Albano, Benjamin; Spencer, Joseph; Lundh, James Spencer; Wang, Boyan; Buttay, Cyril; Tadjer, Marko; DiMarino, Christina; Zhang, Yuhao (February 2023, Journal of Physics D: Applied Physics)

   Abstract Power semiconductor devices are fundamental drivers for advances in power electronics, the technology for electric energy conversion. Power devices based on wide-bandgap (WBG) and ultra-wide bandgap (UWBG) semiconductors allow for a smaller chip size, lower loss and higher frequency compared with their silicon (Si) counterparts, thus enabling a higher system efficiency and smaller form factor. Amongst the challenges for the development and deployment of WBG and UWBG devices is the efficient dissipation of heat, an unavoidable by-product of the higher power density. To mitigate the performance limitations and reliability issues caused by self-heating, thermal management is required at both device and package levels. Packaging in particular is a crucial milestone for the development of any power device technology; WBG and UWBG devices have both reached this milestone recently. This paper provides a timely review of the thermal management of WBG and UWBG power devices with an emphasis on packaged devices. Additionally, emerging UWBG devices hold good promise for high-temperature applications due to their low intrinsic carrier density and increased dopant ionization at elevated temperatures. The fulfillment of this promise in system applications, in conjunction with overcoming the thermal limitations of some UWBG materials, requires new thermal management and packaging technologies. To this end, we provide perspectives on the relevant challenges, potential solutions and research opportunities, highlighting the pressing needs for device–package electrothermal co-design and high-temperature packages that can withstand the high electric fields expected in UWBG devices. 

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4. Wide binaries from the H3 survey: the thick disc and halo have similar wide binary fractions

   https://doi.org/10.1093/mnras/stac650  

   Hwang, Hsiang-Chih; Ting, Yuan-Sen; Conroy, Charlie; Zakamska, Nadia L; El-Badry, Kareem; Cargile, Phillip; Zaritsky, Dennis; Chandra, Vedant; Han, Jiwon Jesse; Speagle, Joshua S; et al (April 2022, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT Due to the different environments in the Milky Way’s disc and halo, comparing wide binaries in the disc and halo is key to understanding wide binary formation and evolution. By using Gaia Early Data Release 3, we search for resolved wide binary companions in the H3 survey, a spectroscopic survey that has compiled ∼150 000 spectra for thick-disc and halo stars to date. We identify 800 high-confidence (a contamination rate of 4 per cent) wide binaries and two resolved triples, with binary separations mostly between 103 and 105 au and a lowest [Fe/H] of −2.7. Based on their Galactic kinematics, 33 of them are halo wide binaries, and most of those are associated with the accreted Gaia-Sausage-Enceladus galaxy. The wide binary fraction in the thick disc decreases toward the low metallicity end, consistent with the previous findings for the thin disc. Our key finding is that the halo wide binary fraction is consistent with the thick-disc stars at a fixed [Fe/H]. There is no significant dependence of the wide binary fraction on the α-captured abundance. Therefore, the wide binary fraction is mainly determined by the iron abundance, not their disc or halo origin nor the α-captured abundance. Our results suggest that the formation environments play a major role for the wide binary fraction, instead of other processes like radial migration that only apply to disc stars. 

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5. Wide-angle effects for peculiar velocities

   https://doi.org/10.1093/mnras/staa2129  

   Castorina, Emanuele; White, Martin (October 2020, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT The line-of-sight peculiar velocities of galaxies contribute to their observed redshifts, breaking the translational invariance of galaxy clustering down to a rotational invariance around the observer. This becomes important when the line-of-sight direction varies significantly across a survey, leading to what are known as ‘wide-angle’ effects in redshift-space distortions. Wide-angle effects will also be present in measurements of the momentum field, i.e. the galaxy density-weighted velocity field, in upcoming peculiar velocity surveys. In this work, we study how wide-angle effects modify the predicted correlation function and power spectrum for momentum statistics, both in autocorrelation and in cross-correlation with the density field. Using both linear theory and the Zel'dovich approximation, we find that deviations from the plane-parallel limit are large and could become important in data analysis for low-redshift surveys. We point out that even multipoles in the cross-correlation between density and momentum are non-zero regardless of the choice of line of sight, and therefore contain new cosmological information that could be exploited. We discuss configuration space, Fourier space, and spherical analyses; providing exact expressions in each case rather than relying on an expansion in small angles. We hope these expressions will be of use in the analysis of upcoming surveys for redshift-space distortions and peculiar velocities. 

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