Effects of LESA in Three-Dimensional Supernova Simulations with Multi-Dimensional and Ray-by-Ray-plus Neutrino Transport

A set of eight self-consistent, time-dependent supernova (SN) simulations in three spatial dimensions (3D) for 9 solar-mass and 20 solar-mass progenitors is evaluated for the presence of dipolar asymmetries of the electron lepton-number emission as discovered by Tamborra et al. and termed lepton-number emission self-sustained asymmetry (LESA). The simulations were performed with the Aenus-Alcar neutrino/hydrodynamics code, which treats the energy- and velocity-dependent transport of neutrinos of all flavors by a two-moment scheme with algebraic M1 closure. For each of the progenitors, results with fully multi-dimensional (FMD) neutrino transport and with ray-by-ray-plus (RbR+) approximation are considered for two different grid resolutions. While the 9 solar-mass models develop explosions, the 20 solar-mass progenitor does not explode with the employed version of simplified neutrino opacities. In all 3D models we observe the growth of substantial dipole amplitudes of the lepton-number (electron neutrino minus antineutrino) flux with stable or slowly time-evolving direction and overall properties fully consistent with the LESA phenomenon. Models with RbR+ transport develop LESA dipoles somewhat faster and with temporarily higher amplitudes, but the FMD calculations exhibit cleaner hemispheric asymmetries with a far more dominant dipole. In contrast, the RbR+ results display much wider multipole spectra of the neutrino-emission anisotropies with significant power also in the quadrupole and higher-order modes. Our results disprove speculations that LESA is a numerical artifact of RbR+ transport. We also discuss LESA as consequence of a dipolar convection flow inside of the nascent neutron star and establish, tentatively, a connection to Chandrasekhar's linear theory of thermal instability in spherical shells.Comment: 20 pages, 9 figures; revised version accepted by ApJ; new Figs. 6,7, and new panels in Fig.8 added; Sects. 4,5,6 considerably extended in reply to referee question

Marxists in the Nigerian labour movement: a case study in the failure of ideology.

Massachusetts Institute of Technology. Dept. of Political Science. Thesis. 1967. Ph.D.Bibliography: leaves 260-277.Ph.D

Striations in a plasma column

An investigation into wave interactions between self-excited ionization waves - striations - in the positive column of a direct current argon discharge is described. Since such self-excited ionization waves are determined by the ionization processes in the discharge, they are inherently nonlinear and a variety of nonlinear effects may be observed.After reviewing the theory and experimental observations for small amplitude linear ionization waves in gas discharges, experimental data obtained from an argon discharge, 5 cm in diameter, 110 cms in length, run at gas pressures between 0.1- 1.5 torr and discharge currents of 20- 250mA, are presented. Linear interactions between large amplitude self-excited waves of the same frequency, and nonlinear mode coupling between waves of different frequencies and wave numbers are reported and the characteristics of each wave type are described. In order to interpret some of the phenomena observed for the self-excited waves, experiments where an external alternating voltage was applied across the discharge were performed. Following a general discussion of wave modulation the wave-wave mode coupling is interpreted as due to nonlinear interactions which may arise during the initial nonlinear growth of ionization waves. A physical model for the nonlinear behaviour is described. By including a nonlinear term in the basic theory of striations expressions are derived which account for the mode-coupling and support the physical interpretation.- 2 -Theoretical techniques previously used to describe the nonlinear behaviour of water waves are outlined, and then applied to ionization waves to predict further nonlinear effects which could not be obtained from the modified linear theory. Finally, a general overall view of two-wave interactions between ionization waves in a discharge is presented using, as an example, the results from a neon discharge. The experimental observations are related to the linear and nonlinear growth of the waves.<p

The Ursinus Weekly, December 8, 1941

Guest vocalists and musical organizations will blend talents in Messiah presentation • Wenhold tells vespers that giving is one of most important virtues • First forum hears discussion of the post-war world • Gordon airs and novel tavern party to highlight gala senior weekend • President McClure calls for balance in time of crisis • Dr. N. W. Winkelman, Penn neurology prof, to address pre-meds • Michael named member of survey committee for secondary schools • Ursinus ranks high in grad school placements; stands 47th in survey of 215 leading colleges • Rec hall to have host, hostess; Appleget plans novelty events • Bomberger memorial maintains unceasing vigil as it celebrates completion of fiftieth year • Federal government to levy 10% tax on admissions to college activities • John and David Garvey present music recital in Bomberger Hall • Bear quintet faces Lehigh in season\u27s opener this Saturday • Twenty-one wrestlers prepare for opener against Kutztown Wednesday • Co-eds have last year\u27s team intact for season\u27s play • Jing Johnson announces athletic award winners • Captains elected! • 20 frosh candidates drill for season\u27s play under coach Pancoast • G-burg\u27s Bullets dominate bears opponent team; Petro unanimous • Bears make all teams of opponents and scribes • Giving: the spirit of Christmas • Vickland and Jamison to handle soprano, tenor parts in Messiahhttps://digitalcommons.ursinus.edu/weekly/1772/thumbnail.jp

The Ursinus Weekly, November 10, 1941

Koch holds out hope of better day at vesper service • College poll shows division of opinion on war question • Two speakers at Fathers\u27 Day banquet depict qualities of the ideal college • Pre-medders hear talk on autonomic nervous system by Doctor Price • Well known woman lecturer will speak to AAUW tonight • Activities of Y include freshman drive, paper, and Christmas charity • Juniors lure sophs on wild goose chase; prexy at banquet intact • Pageant committee sets December 19 as last date for manuscript • Class of \u2741 turns to grad schools, vocations, defense • Librarian lauds contributions of Class of 1914; indicates potential effect a single gift might have • Weekly reporter writes \u27biographical\u27 sketch of science building; a dream becomes reality • Big-little sisters plan for movie party next Wednesday • Washington College ties bears Saturday, 0-0, in Fathers\u27 Day classic; bear cubs lose to Brown prep by 14-6 score • Baker soccermen drop close game to Delaware, 3-1 • Co-eds meet Rhode Island, Penn, and Drexel this week • Final grizzly gridder carries article by Harold Steward \u2707 • Grad testifies to value of college debating in making law work easy • Men schedule radio debate Sunday as season\u27s opener • Beardwood Chemical Society to see movie, Alloy metalshttps://digitalcommons.ursinus.edu/weekly/1768/thumbnail.jp

Design and analysis of low boom concepts at Langley Research Center

The objective of the sonic boom research in the current High Speed Research Program is to ultimately make possible overland supersonic flight by a high speed civil transport. To accomplish this objective, it is felt that results in four areas must demonstrate that such a vehicle would be acceptable by the general public, by the airframers, and by the airlines. It should be demonstrated: (1) that some waveform shape has the possibility of being acceptable to the general public; (2) that the atmosphere would not totally destroy such a waveform during propagation; (3) that a viable airplane could be built which produces such a waveform; and (4) that any performance penalty suffered by a low boom aircraft would be counteracted by the economic benefit of overland supersonic flight. The work being done at LaRC is in support of the third element listed above--the area of configuration design. The initial part of the paper will give a review of the theory being used for configuration designs and discuss two theory validation models which were built and tested within the past two years. Discussion of the wind tunnel and theoretical results (linear theory and higher order methods) and their implications for future designs will be included

Socio-demographic factors associated with pet ownership amongst adolescents from a UK birth cohort

Background: In developed nations, pet ownership is common within families. Both physical and psychological health benefits may result from owning a pet during childhood and adolescence. However, it is difficult to determine whether these benefits are due to pet ownership directly or to factors linked to both pet ownership and health. Previous research found associations between a range of socio-demographic factors and pet ownership in seven-year-old children from a UK cohort. The current study extends this research to adolescence, considering that these factors may be important to consider in future Human-Animal Interaction (HAI) research across childhood.Results:The Avon Longitudinal Study of Parents and Children (ALSPAC) collected pet ownership data prospectively via maternal reports from gestation up to age 10 years old and via self-report retrospectively at age 18 for ages 11(n= 3063) to 18 years old (n= 3098) on cats, dogs, rabbits, rodents, birds, fish, tortoise/turtles and horses. The dataset also contains a wide range of potential confounders, including demographic and socio-economic variables.The ownership of all pet types peaked at age 11 (80%) and then decreased during adolescence, with the exclusion of cats which remained constant (around 30%), and dogs which increased through 11–18 years (26–37%). Logistic regression was used to build multivariable models for ownership of each pet type at age 13 years, and the factors identified in these models were compared to previously published data for 7 year-olds in the same cohort. There was some consistency with predictors reported at age 7. Generally sex, birth order, maternal age, maternal education, number of people in the household, house type, and concurrent ownership of other pets were associated with pet ownership at both 7 and 13 years (the direction of association varied according to pet type).Factors that were no longer associated with adolescent pet ownership included child ethnicity, paternal education,and parental social class.Conclusions:A number of socio-demographic factors are associated with pet ownership in childhood and adolescence and they differ according to the type of pet, and age of child. These factors are potential confounders that must be considered in future HAI studies

Beyond national narratives? : centenary histories, the First World War and the Armenian Genocide

In April 2015 the centenary of the Armenian Genocide was commemorated. Just like the First World War centenary, this anniversary has provoked a flurry of academic and public interest in what remains a highly contested history. This article assesses the state of the current historiography on the fate of the Ottoman Armenians. It focuses on the possibilities for moving beyond the national narratives which continue to dominate the field, in particular through connecting the case of the Armenian Genocide to what has been termed a ‘transnational turn’ in the writing of the history of the First World War