scholarly journals Measurements of the direction of the solar wind using interplanetary scintillation

1998 ◽  
Vol 16 (10) ◽  
pp. 1259-1264 ◽  
Author(s):  
P. J. Moran ◽  
A. R. Breen ◽  
C. A. Varley ◽  
P. J. S. Williams ◽  
W. P. Wilkinson ◽  
...  
Keyword(s):  
Solar Wind ◽  
Plasma Flow ◽  
Solar Physics ◽  
Extended Period ◽  
Radial Component ◽  
Unique Determination ◽  
Interplanetary Scintillation ◽  
Maximum Correlation ◽  
The Past

Abstract. EISCAT observations of the interplanetary scintillation of a single source were made over an extended period of time, during which the orientation of the baselines between the two observing sites changed significantly. Assuming that maximum correlation between the scintillations observed at the two sites occurs when the projected baseline is parallel to the direction of plasma flow, this technique can be used to make a unique determination of the direction of the solar wind. In the past it has usually been assumed that the plasma flow is radial, but measurements of eleven sources using this technique have indicated conclusively that in at least six cases observed at mid or high heliocentric latitude there is a significant non-radial component directed in four cases towards the heliocentric equator and in two cases towards the pole.Key words. Solar physics · Astrophysics · Astronomy · Magnetic fields · Space plasma physics · Charged particle motion and acceleration

scholarly journals Observations of interplanetary scintillation during the 1998 Whole Sun Month: a comparison between EISCAT, ORT and Nagoya data

2000 ◽  
Vol 18 (9) ◽  
pp. 1003-1008 ◽  
Author(s):  
P. J. Moran ◽  
S. Ananthakrishnan ◽  
V. Balasubramanian ◽  
A. R. Breen ◽  
A. Canals ◽  
...  
Keyword(s):  
Solar Wind ◽  
Solar Wind Velocity ◽  
Solar Physics ◽  
Solar Wind Plasma ◽  
Interplanetary Scintillation ◽  
Velocity Measurements ◽  
Plasma Sources ◽  
Interplanetary Physics ◽  
Instruments And Techniques ◽  
Good Agreement

Abstract. Observations of interplanetary scintillation (IPS) allow accurate solar wind velocity measurements to be made at all heliographic latitudes and at a range of distances from the Sun. The data may be obtained with either single, double or multiple antennas, each requiring a different method of analysis. IPS data taken during the 1998 whole sun month (30th July-31st August 1998) by EISCAT, the ORT (Ooty Radio Telescope), India, and the Nagoya IPS system, Japan, allow the results of individual methods of analysis to be compared. Good agreement is found between the velocity measurements using each method, and when combined an improved understanding of the structure of the solar wind can be obtained.Key words: Interplanetary physics (solar wind plasma; sources of the solar wind) - Solar physics, astrophysics and astronomy (instruments and techniques)

scholarly journals Four Subjects in Solar Physics from the Point of View of the Electric Current Approach

2020 ◽  
pp. 33-45
Author(s):  
Syun-Ichi Akasofu
Keyword(s):  
Solar Wind ◽  
Electric Current ◽  
Solar Flares ◽  
Solar Physics ◽  
Current Approach ◽  
Point Of View ◽  
Coronal Temperature ◽  
The Past ◽  
Electromagnetic Processes ◽  
Difficult Subjects

Four major subjects in solar physics, the heating of the corona, the cause of the solar wind, the formation of sunspots and the cause of solar flares, are discussed on the basis of the electric current approach, a sequence of processes consisting of power supply(dynamo), transmission (currents/circuits) and dissipation(high coronal temperature, solar wind, sunspots and solar flares).This is because the four subjects have hardly been considered in terms of the electric current approach in the past, in spite of the fact that these subjects are various manifestations of electromagnetic processes. It is shown that this approach provides a new systematic way of considering each subject; (1) the long-standing issue of the coronal temperature, (2)the long-standing problem on the cause of the solar wind, (3)the presence of single spots(forgotten or dismissed in the past) and its relation to unipolar magnetic regions and (4) the crucial power/energy source and subsequent explosive processes of solar flares. The four subjects are obviously extremely complicated and difficult subjects, but it is hoped that the electric current approach might provide a new insight in considering the four subjects.

scholarly journals Quasi-Two-Dimensional Cosmic Jets

1985 ◽  
Vol 107 ◽  
pp. 497-501
Author(s):  
K. Tsinganos ◽  
A. Ferrari ◽  
R. Rosner
Keyword(s):  
Solar Wind ◽  
High Speed ◽  
Solar Physics ◽  
Coronal Holes ◽  
Star Forming ◽  
Ss 433 ◽  
The Past ◽  
Astrophysical Jet ◽  
Speed Solar Wind ◽  
High Speed Solar Wind

One of the major discoveries in solar physics over the past decade has been the association of coronal holes with high-speed solar wind streams (Zirker 1977 and references therein). On the other hand, advances in X-ray and radio instrumentation (e.g., Einstein, VLA, VLBI, etc.) in the past few years have allowed detailed observations of collimated outflows from rather more distant objects, such as young stars and active galaxies (Beer 1981, Lada 1982, Ferrari and Pacholczyk 1983 and references therein). The remarkable structural similarities between jets of magnetized gas from our Sun, other active stars, and active galactic nuclei suggest that these phenomena may be manifestations of similar hydrodynamic processes operating on both small and large scales. In this article, we shall use the experience gained by studying the nearest known astrophysical jet - high-speed solar wind streams - to address some of the problems of astrophysical jet acceleration and collimation associated with objects as diverse as SS 433, star-forming molecular clouds and, in particular, jets associated with galaxies and quasars.

Transmission Electron Microscopy of Protein Macromolecules

1971 ◽  
Vol 29 ◽  
pp. 424-425
Author(s):  
Henry S. Slayter
Keyword(s):  
Biological Systems ◽  
Metal Vapor ◽  
Resolving Power ◽  
Electron Microscopic ◽  
Chemical Methods ◽  
Molecular Weights ◽  
The Past ◽  
Physical Chemical ◽  
Transmission Electron

Electron microscopic methods have been applied increasingly during the past fifteen years, to problems in structural molecular biology. Used in conjunction with physical chemical methods and/or Fourier methods of analysis, they constitute powerful tools for determining sizes, shapes and modes of aggregation of biopolymers with molecular weights greater than 50, 000. However, the application of the e.m. to the determination of very fine structure approaching the limit of instrumental resolving power in biological systems has not been productive, due to various difficulties such as the destructive effects of dehydration, damage to the specimen by the electron beam, and lack of adequate and specific contrast. One of the most satisfactory methods for contrasting individual macromolecules involves the deposition of heavy metal vapor upon the specimen. We have investigated this process, and present here what we believe to be the more important considerations for optimizing it. Results of the application of these methods to several biological systems including muscle proteins, fibrinogen, ribosomes and chromatin will be discussed.

Quantitative surface damage studies by H.R.E.M.

1989 ◽  
Vol 47 ◽  
pp. 632-633
Author(s):  
S. R. Singh ◽  
H. J. Fan ◽  
L. D. Marks
Keyword(s):  
Solar Wind ◽  
Quantitative Analysis ◽  
Surface Science ◽  
Surface Damage ◽  
Space Environment ◽  
Oxygen Desorption ◽  
The Past ◽  
Diffusion Controlled ◽  
Original Observation ◽  
Substantial Interest

Since the original observation that the surfaces of materials undergo radiation damage in the electron microscope similar to that observed by more conventional surface science techniques there has been substantial interest in understanding these phenomena in more detail; for a review see. For instance, surface damage in a microscope mimics damage in the space environment due to the solar wind and electron beam lithographic operations.However, purely qualitative experiments that have been done in the past are inadequate. In addition, many experiments performed in conventional microscopes may be inaccurate. What is needed is careful quantitative analysis including comparisons of the behavior in UHV versus that in a conventional microscope. In this paper we will present results of quantitative analysis which clearly demonstrate that the phenomena of importance are diffusion controlled; more detailed presentations of the data have been published elsewhere.As an illustration of the results, Figure 1 shows a plot of the shrinkage of a single, roughly spherical particle of WO3 versus time (dose) driven by oxygen desorption from the surface.

Crime and Punishment

2017 ◽  
Author(s):  
Richard Adelstein
Keyword(s):  
Criminal Liability ◽  
Court Case ◽  
Efficient Allocation ◽  
Two Stage ◽  
Crime And Punishment ◽  
The Past ◽  
Ex Post ◽  
Ex Ante ◽  
Supreme Court Case

This chapter elaborates the operation of criminal liability by closely considering efficient crimes and the law’s stance toward them, shows how its commitment to proportional punishment prevents the probability scaling that systemically efficient allocation requires, and discusses the procedures that determine the actual liability prices imposed on offenders. Efficient crimes are effectively encouraged by proportional punishment, and their nature and implications are examined. But proportional punishment precludes probability scaling, and induces far more than the systemically efficient number of crimes. Liability prices that match the specific costs imposed by the offender at bar are sought through a two-stage procedure of legislative determination of punishment ranges ex ante and judicial determination of exact prices ex post, which creates a dilemma: whether to price crimes accurately in the past or deter them accurately in the future. An illustrative Supreme Court case bringing all these themes together is discussed in conclusion.

The Afterlife of a Tribunal

2018 ◽  
Author(s):  
Diane Orentlicher
Keyword(s):  
Extended Period ◽  
German Society ◽  
Norm Diffusion ◽  
Postwar Germany ◽  
The Past ◽  
Operational Life ◽  
Local Impact

The span of an international tribunal’s local impact is not the same as its operational life, as Germany’s evolved relationship with Nuremberg highlights. Recognizing that the ICTY’s impact in Bosnia and Serbia will continue to evolve after the Tribunal ends its work, this chapter considers the Tribunal’s future impact, focusing in particular on its potential to stimulate a future reckoning with Serbia’s wartime past. While recognizing myriad differences between post-Milošević Serbia and postwar Germany, this chapter explores factors behind the latter’s eventual emergence as a “model penitent” long after German society rejected the moral message the Allies hoped Nuremberg would impart. It suggests that, after an extended period of “transitional denial,” Nuremberg may have contributed to Germany’s far-reaching reckoning with the past through a process of delayed norm diffusion.

Sampling, Preservation and Counting of Samples II: Zooplankton

2017 ◽  
Author(s):  
Peter H. Wiebe ◽  
Ann Bucklin ◽  
Mark Benfield
Keyword(s):  
Genetic Analysis ◽  
High Speed ◽  
Morphological Analysis ◽  
Taxonomic Composition ◽  
Sampling Techniques ◽  
Sample Analysis ◽  
Sample Preservation ◽  
The Past ◽  
Plankton Collection

This chapter reviews traditional and new zooplankton sampling techniques, sample preservation, and sample analysis, and provides the sources where in-depth discussion of these topics is addressed. The net systems that have been developed over the past 100+ years, many of which are still in use today, can be categorized into eight groups: non-opening/closing nets, simple opening/closing nets, high-speed samplers, neuston samplers, planktobenthos plankton nets, closing cod-end samplers, multiple net systems, and moored plankton collection systems. Methods of sample preservation include preservation for sample enumeration and taxonomic morphological analysis, and preservation of samples for genetic analysis. Methods of analysis of zooplankton samples include determination of biomass, taxonomic composition, and size by traditional methods; and genetic analysis of zooplankton samples.

scholarly journals Analysis of the Mycosporine-Like Amino Acid (MAA) Pattern of the Salt Marsh Red Alga Bostrychia scorpioides

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 321
Author(s):  
Maria Orfanoudaki ◽  
Anja Hartmann ◽  
Julia Mayr ◽  
Félix L. Figueroa ◽  
Julia Vega ◽  
...  
Keyword(s):  
Amino Acids ◽  
High Performance Liquid Chromatography ◽  
High Performance ◽  
Red Alga ◽  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
The Past ◽  
Specific Species

This study presents the validation of a high-performance liquid chromatography diode array detector (HPLC-DAD) method for the determination of different mycosporine-like amino acids (MAAs) in the red alga Bostrychia scorpioides. The investigated MAAs, named bostrychines, have only been found in this specific species so far. The developed HPLC-DAD method was successfully applied for the quantification of the major MAAs in Bostrychia scorpioides extracts, collected from four different countries in Europe showing only minor differences between the investigated samples. In the past, several Bostrychia spp. have been reported to include cryptic species, and in some cases such as B. calliptera, B. simpliciuscula, and B. moritziana, the polyphyly was supported by differences in their MAA composition. The uniformity in the MAA composition of the investigated B. scorpioides samples is in agreement with the reported monophyly of this Bostrychia sp.

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