bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Origin of SN 2016hil—A Type II Supernova in the Remote Outskirts of an Elliptical Host
Authors: Irani Ido , Schulze Steve , Gal-Yam Avishay , Lunnan Ragnhild , Brink Thomas G. , Zheng WeiKang , Filippenko Alexei V. , Yang Yi , de Jaeger Thomas , Nugent Peter E. , Kasliwal Mansi M. , Fremling Christoffer , Neill James Don , Rebbapragada Umaa , Masci Frank J. , Sollerman Jesper , Yaron Ofer 
Published: December 2019

Abstract
Type II supernovae (SNe) stem from the core collapse of massive (>8 M
⊙) stars. Due to their short lifespan, we expect a very low rate of such events in elliptical hosts, where the star formation rate is low, and which are mostly comprised of an old stellar population. SN 2016hil (iPTF16hil) is an SN II located in the extreme outskirts of an elliptical galaxy at z = 0.0608 (projected distance 27.2 kpc). It was detected near peak (M

r
∼ −17 mag) 9 days after the last non-detection. The event has some potentially peculiar properties: it presented an apparently double-peaked light curve, and its spectra suggest low metallicity content (Z < 0.4 Z
⊙). We place a tentative upper limit on the mass of a potential faint host at

using deep optical imaging from Keck/LRIS. In light of this, we discuss the possibility of the progenitor forming locally and other more exotic formation scenarios such as a merger or common-envelope evolution causing a time-delayed explosion. Further observations of the explosion site in the UV are needed in order to distinguish between the cases. Regardless of the origin of the transient, observing a population of such seemingly hostless SNe II could have many uses, including an estimate the amount of faint galaxies in a given volume, and tests of the prediction of a time-delayed population of core-collapse SNe in locations otherwise unfavorable for the detection of such events.
The Structure of Solar Coronal Mass Ejections in the Extreme-ultraviolet Passbands
Authors: Song H. Q. , Zhang J. , Li L. P. , Liu Y. D. , Zhu B. , Wang B. , Zheng R. S. , Chen Y. 
Published: December 2019

Abstract
So far, most studies on the structure of coronal mass ejections (CMEs) are conducted through white-light coronagraphs, demonstrating that about one third of CMEs exhibit the typical three-part structure in the high corona (e.g., beyond 2

), i.e., the bright front, the dark cavity, and the bright core. In this paper, we address the CME structure in the low corona (e.g., below 1.3

) through extreme-ultraviolet (EUV) passbands and find that the three-part CMEs in the white-light images can possess a similar three-part appearance in the EUV images, i.e., a leading edge, a low-density zone, and a filament or hot channel. The analyses identify that the leading edge and the filament or hot channel in the EUV passbands evolve into the front and the core later within several solar radii in the white-light passbands, respectively. What is more, we find that the CMEs without an obvious cavity in the white-light images can also exhibit the clear three-part appearance in the EUV images, which means that the low-density zone in the EUV images (observed as the cavity in white-light images) can be compressed and/or transformed gradually by the expansion of the bright core and/or the reconnection of the magnetic field surrounding the core during the CME propagation outward. Our study suggests that more CMEs can possess the clear three-part structure in their early eruption stage. The nature of the low-density zone between the leading edge and the filament or hot channel is discussed.
Anisotropic Mass Segregation in Rotating Globular Clusters
Authors: Szölgyén Ákos , Meiron Yohai , Kocsis Bence 
Published: December 2019

Abstract
We investigate the internal dynamics of anisotropic, rotating globular clusters with a multimass stellar population by performing new direct N-body simulations. In addition to the well-known radial mass segregation effect, where heavy stars and stellar remnants sink toward the center of the cluster, we find a mass segregation in the distribution of orbital inclinations as well. This newly discovered anisotropic mass segregation leads to the formation of a disk-like structure of massive objects near the equatorial plane of a rotating cluster. This result has important implications on the expected spatial distribution of black holes in globular clusters.
The Generalized Ion-sound Speed in Space and Astrophysical Plasmas
Authors: Saberian E. 
Published: December 2019

Abstract
A generalized ion-sound speed for space and astrophysical plasmas in the regions of near- and far-from-thermal equilibrium is derived in the context of the new formulated invariant Kappa distribution. Inspired by the recent studies on the origin of polytropic behavior in space plasmas, it has been shown that the sound speed is connected to the extended polytropic index of Kappa distributed particles, which itself depends on the invariant Kappa index and the potential degrees of freedom. Generally, the ion-sound speed is a function of the polytropic index of Kappa distributed particles, which varies between two asymptotic regions of equilibrium and anti-equilibrium states. It is found that the ion-sound speed takes its maximum value in an equilibrium plasma and it reduces by approaching to the anti-equilibrium states. Furthermore, dispersion relation of the ion-acoustic waves in our formulism confirms, correspondingly, the recent study on the generalized formulation of Debye shielding in space plasmas. Finally, the classical and generalized relations between the ion-sound speed, the Debye length and the ion oscillation frequency have been discussed.
Unbiased Differential Size Evolution and the Inside-out Growth of Galaxies in the Deep CANDELS GOODS Fields at 1 ≤ z ≤ 7
Authors: Whitney A. , Conselice C. J. , Bhatawdekar R. , Duncan K. 
Published: December 2019

Abstract
We present a size analysis of a sample of ∼49,000 galaxies from the Cosmic Assembly Near-infrared Deep Extragalactic Survey GOODS North and South fields, using redshift-independent relative surface-brightness metrics to determine an unbiased measure of the differential size evolution of galaxies at 1 ≤ z ≤ 7. We introduce a novel method of removing foreground objects from distant galaxy (z > 3) images that makes use of the Lyman break at 912 Å, in what we call “2D Lyman-break imaging.” The images used are in the rest-frame optical at z < 3 and progressively bluer bands at z > 3. They are therefore subject to K-correction and cosmological dimming effects, which are tested and corrected for. We separately consider a mass-selected sample (with masses in the range 109
M
⊙ ≤ M
* ≤ 1010.5
M
⊙) and a number-density-selected sample (using a constant number density of n = 1 × 10−4Mpc−3). Instead of utilizing the commonly used, but potentially biased, effective radii for size measurements, we measure the redshift-independent Petrosian radius, defined by the parameter η, for each galaxy for three values of η, and use this as a proxy for size. The evolution of the measured radii can be described by a power law of the form R
Petr = α(1+z)
β
kpc where β < 0. We find that the outer radius increases more rapidly, suggesting that as a galaxy grows, mass is added to its outer regions via an inside-out growth. This growth is stronger for the number-density-selected sample, with a growth rate of nearly three in the outer radii compared to the inner. We test and confirm these results using a series of image simulations.
Star Formation Histories of the LEGUS Dwarf Galaxies. III. The Nonbursty Nature of 23 Star-forming Dwarf Galaxies*
Authors: Cignoni M. , Sacchi E. , Tosi M. , Aloisi A. , Cook D. O. , Calzetti D. , Lee J. C. , Sabbi E. , Thilker D. A. , Adamo A. , Dale D. A. , Elmegreen B. G. , Gallagher J. S. , Grebel E. K. , Johnson K. E. , Messa M. , Smith L. J. , Ubeda L. 
Published: December 2019

Abstract
We derive the recent star formation histories (SFHs) of 23 active dwarf galaxies using Hubble Space Telescope observations from the Legacy Extragalactic UV Survey. We apply a color–magnitude diagram (CMD) fitting technique using two independent sets of stellar models, PARSEC-COLIBRI and MIST. Despite the nonnegligible recent activity, none of the 23 star-forming dwarfs show enhancements in the last 100 Myr larger than three times the 100 Myr average. The unweighted mean of the individual SFHs in the last 100 Myr is also consistent with a rather constant activity, irrespective of the atomic gas fraction. We confirm previous results that for dwarf galaxies, the CMD-based average star formation rates (SFRs) are generally higher than the FUV-based SFRs. For half of the sample, the 60 Myr average CMD-based SFR is more than two times the FUV SFR. In contrast, we find remarkable agreement between the 10 Myr average CMD-based SFR and the Hα-based SFR. Finally, using core helium-burning stars of intermediate mass, we study the pattern of star formation spatial progression over the past 60 Myr and speculate on the possible triggers and connections of the star formation activity with the environment in which these galaxies live. Approximately half of our galaxies show spatial progression of star formation in the last 60 Myr and/or very recent diffuse and off-center activity compared to RGB stars.
Multi-wavelength Variability Signatures of Relativistic Shocks in Blazar Jets
Authors: Böttcher Markus , Baring Matthew G. 
Published: December 2019

Abstract
Mildly relativistic shocks that are embedded in colliding magnetohydrodynamic flows are prime sites for relativistic particle acceleration and the production of strongly variable, polarized multi-wavelength emission from relativistic jet sources such as blazars and gamma-ray bursts. The principal energization mechanisms at these shocks are diffusive shock acceleration and shock drift acceleration. In recent work, we had self-consistently coupled shock acceleration and radiation transfer simulations in blazar jets in a basic one-zone scenario. These one-zone models revealed that the observed spectral energy distributions (SEDs) of blazars strongly constrain the nature of the hydromagnetic turbulence in the shock layer. In this paper, we expand our previous work by including full time dependence and treating two zones, one being the site of acceleration and the other a larger emission zone. This construction is applied to multi-wavelength flares of the flat-spectrum radio quasar (FSRQ) 3C 279, fitting snapshot SEDs and generating light curves that are consistent with observed variability timescales. We also present a generic study for the typical flaring behavior of the BL Lac object Mrk 501. The model predicts correlated variability across all wavebands, but cross-band time lags depending on the type of blazar (FSRQ versus BL Lac), as well as distinctive spectral hysteresis patterns in all wavelength bands, from millimeter radio waves to gamma-rays. These evolutionary signatures serve to provide diagnostics on the competition between acceleration and radiative cooling.
The study of the endothelial protective properties of the L-norvaline combination with mexidol in the simulation of L-NAME-induced NO deficiency
Authors: Konovalova Elena A. , Chernomortseva Elena S. 
Published: December 2019

Introduction: The endothelium is considered as a target for the prevention and treatment of pathological processes leading to cardiovascular diseases.
Materials and methods: Endothelial dysfunction was simulated in male rats using an e-NOS inhibitor L-NAME (25 mg/kg/day intraperitoneally, 7 days). This pathology was then corrected by administering mexidol at a dose of 60 mg/kg and L-norvaline at a dose of 10 mg/kg, as well as the combination of both at the same doses, intragastrically, through an atraumatic probe, once a day.
Results and discussion: A combination of L-norvaline at a dose of 10 mg/kg and mexidol at a dose of 60 mg/kg against the background of L-NAME-induced endothelial dysfunction has a pronounced endothelial protective effect. This is reflected in the prevalence of endothelial-dependent vascular relaxation, a significant decrease in the coefficient of endothelial dysfunction, as well as the prevention of a decline in the concentrations of stable nitric oxide metabolites and of a decrease in the level of the inflammatory changes marker in the vascular wall. The combination of L-norvaline and mexidol, with different pathogenetic action mechanisms, has a pronounced endothelial protective effect because of their antioxidant properties (mexidol) and donation of nitric oxide (L-arginine).
Conclusion: The investigated drugs showed pronounced endothelial protective activity and can be recommended for further pre-clinical studies.
Ferrites in Transfer Molded Power SiPs – Challenges in Packaging
Authors: Thomas Tina , van Dijk Marius , Dreissigacker Marc , Hoffmann Stefan , Walter Hans , Becker Karl-Friedrich , Schneider-Ramelow Martin 
Published: December 2019

Abstract
Transfer-Molding-Process is enjoying growing interest when aiming for novel high-power density System-in-Packages (Power SiPs), where not only transistors and diodes, but also drivers, passives, coils and transformers are supposed to be integrated in one package. Encapsulating modules in a Transfer-Molding-Process induces higher mechanical load onto module components compared to conventional silicone potting. Previous investigations have shown, that integration of delicate components as ferrite cores into molded packages is not as trivial as integration of conventional Surface Mount Devices (SMDs) or power semiconductors; the brittle ferrites tend to fracture during the encapsulation process, resulting in higher ferrite core loss. The present study aims to identify main root causes for ferrite core cracking during manufacturing of molded Power SiPs.
The test vehicle is a symmetrical Printed Circuit Board (PCB) based package with three pairs of E-shaped ferrite cores. The Epoxy Molding Compound (EMC) deployed here is characterized to enable filling simulations. Since technical datasheets of ferrites typically lack specifications of mechanical properties, ferrite materials are analyzed in more detail.
Filling simulations and thermo-mechanical simulations are performed in order to gain insight into process-induced stress, which may induce cracks in the ferrites. In addition, different ferrite designs are evaluated regarding core losses and mechanical stability, and thus their tendency to fracture.
A New Halogen-Free Parylene for High Performance & Reliability of Microelectronics in Harsh Environments
Authors: Kumar Rakesh , Ke Frank , England Dustin , Summers Angie , Young Lamar 
Published: December 2019

Abstract
The rapid growth and adoption of microelectronics around the world has resulted in an increased awareness of potential environmental issues related to their use and disposal. Halogens, which have had various uses in microelectronics over the years, are known to emit toxic and corrosive gases during the disposal of electronic waste. Many organizations have applied pressure to the electronics industry to eliminate halogens completely (e.g., fluorine, chlorine and bromine) from their products. Among the various efforts towards environmentally-friendly products, making electronics completely halogen-free has gained significant attention, particularly in Asia and Europe. This initiative even impacts conformal coatings worldwide, on which most electronics rely for their long-term protection, reliability and high performance against water and other corrosive harsh environments.
Among the various coating options, the Parylene family of conformal coatings offers beneficial properties to the microelectronics, improved over many properties offered by common epoxies, acrylics, urethanes and silicones. While Parylene N is the only commercially available Parylene that does not contain any halogens, its barrier performance against moisture and other corrosive chemicals is not quite as robust as the other Parylenes. To meet the industry's current and future requirements, a new halogen-free Parylene, ParyFree®, has been developed.
This paper introduces a new Parylene type to the microelectronics industry and shares the characterization and qualification results of ParyFree® Parylene conformal coating for the protection, reliability and robust performance of microelectronics. Testing on the new coating includes IPX water resistance, corrosion resistance and qualification per IPC-CC-830B.
Thin Glass Substrates with Through-Glass Vias.
Authors: Shorey Aric , Nelson Shelby , Levy David , Ballentine Paul 
Published: December 2019

Abstract
Glass substrates with fine-pitch through-glass via (TGV) technology is a promising approach to system in a package (SIP) integration. Millimeter wave applications, in particular, benefit from the superior RF properties, dimensional stability, and surface properties of glass. Glass can be made in very thin sheets (&lt;200 um) which aids in integration and eliminates the need for back-grinding operations. The biggest challenge to adopting glass as a microelectronics packaging substrate is the existence of gaps in the supply chain, caused primarily by the difficulty in handling large, thin glass substrates using existing automation and processing equipment. This paper presents a temporary bonding technology that allows the substrates to be processed in a semiconductor fab environment without the need to modify existing equipment.
Deformable Interconnects with Embedded Devices in Flexible Fan-Out Packages
Authors: Sayeed Sk Yeahia Been , Wilding Daniel , Camara Jose Solis , Vital Dieff , Bhardwaj Shubhendu , Raj P. M 
Published: December 2019

Abstract
A new class of interconnects that exhibit resilience to mechanical deformation are demonstrated with flexible fan-out or embedded-die packages. Active device embedding in flexible substrates is accomplished with direct printed interconnects onto die pads. Such a planar fan-out interconnect technology with a low-cost manufacturable process-flow results in the lowest electrical parasitics compared to flipchip with adhesives or printed-ramp interconnections with surface-assembled devices. The interconnects are made with conductive flexible silver-elastomer composites to sustain elastic deformation. The process is also modified to realize flexible backside-assembled fan-out interconnections where the backside of the die is accessible.
Cu pillar bump development for 7nm Chip package interaction (CPI) technology
Authors: Fu Lei , Bhagavat Milind , Selvanayagam Cheryl , Leong Ken , Barber Ivor 
Published: December 2019

Abstract
Power, performance, and area gains are important metrics driving the CMOS technology from older nodes to newer ones. Over past several decades, a steady downscaling of feature sizes of CMOS technology has been a leading force enabling continual improvement in circuit speeds and cost per functionality. Increase in functionality drives larger number of I/Os, and the scaling driven small IP block sizes force these larger number of I/Os to be accommodated by reduction of I/O pitches. The result is an unrelenting pressure to reduce bump pitches from one generation of CMOS to another. In contrast to 14nm/16nm nodes which used 150um bump pitch coming out of a die, for 7nm node the industry is targeting 130um bump pitch for high performance devices. With this pitch reduction, conventional SnAg solder bumps face limitations in terms of bridging. Cu pillar bumps are the best candidate for smaller bump pitches. However, for large die sizes prevalent in High Performance Computing, the Cu pillar bumps will induce higher stress on the silicon resulting in higher risks of ELK cracking. If copper pillar bumps are not properly developed, then there is a risk of marginal reliability in terms of chip package interaction. The situation becomes even more dire in large die sizes, where CTE mismatch between silicon and laminate substrate magnifies the stress.
The present paper discusses successful development of Cu pillar bumps for 7nm technology. The development program included a 2-step development path. In the first step, extensive thermo-mechanical modeling was done to find optimal design of copper pillar bump for robustness of interactions with 7nm BEOL ELK layers. In the second step, a 460 mm2 7nm Silicon test Vehicle was fabricated and its assembly process was optimized to characterize the copper pillar bumps and prove their extended reliability on 7nm silicon. As a result of this development, copper pillar technology has been qualified on AMD products. Today, copper pillar is a fully integral part of AMD's ever-growing 7nm product offering in High Performance Computing.
IMPROVE CONTROL AMIDST DIE SHRINKAGE AND 3D PACKAGE COMPLICATION
Authors: Young Woo Han , Marshall Mike 
Published: December 2019

Abstract
Die sizes continue to shrink and packaging technologies continue to evolve, but the common thread for all of them is the need for increased precision and tighter process control limits to achieve final package yield. Nearly all packaging technologies require connections in the third dimension, above or below the die, thus adding, quite literally, a new dimension to inspection and metrology requirements. Increased focus on reliability for automotive, health care and even mobile electronics is driving the need for improved process control solutions. The combination of higher packaging complexity and the need for improved reliability are driving changes to the requirements around inspection and metrology. Vertical integration continues to grow at a pervasive rate and the need for improved process control in the third dimension is growing rapidly in order to ensure reliability. Vertical integration is designed into nearly all packaging forms, including TSV, RDL, WLP, Fan-in, Fan-out, with a focus on continued increase in the number of I/Os, the pitch of features (RDL and bump) and the overall package size increasing. This integration drives the need for 3D metrology of feature height and coplanarity. In addition, the need to augment raw 3D metrology with defect inspection and 2D metrology data enables a comprehensive view (insight) into the packaging process. Achieve total bump process control with the combination of data from: (1) 2D defect detection – voids and shorts, foreign material, misprocessing; (2) 2D metrology – bump diameter, bump position, bump presence; (3) 3D inspection – bump too tall, bump too short, statistical process control (SPC); (4) Auto classifications – data must make sense and be easy to interpret.
By combining high speed 2D, 3D metrology with defect inspection and advanced analytics, the quality of process control data can be exponentially improved to enable quick time-to-results for both process development and HVM control.
This paper describes the inspection and metrology challenges of bumps in advanced packaging and the next generation high-throughput bump inspection methodology for wafers with extremely high bump counts as well as the data analysis