Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Monte Carlo and spin dynamics study of the anisotropic Heisenberg model in two dimensions : The 41st annual conference on magnetism and magnetic materials (1997)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 81 (1997), S. 5746-5748 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: By using Monte Carlo and molecular dynamics we study the static as well as the dynamical behavior of the classical two dimensional anisotropic Heisenberg model. Our results show that the vortices developed in such a model exhibit two different behaviors depending if the value of the anisotropy λ lies below or above a critical value λc. The in-plane and out-of-plane correlation functions were obtained numerically for λ〈λc and λ〉λc. We found that the out-of-plane dynamical correlation function exhibits a central peak for λ〉λc but not for λ〈λc at temperatures above TKT. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.364712
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Sub-second pulsations simultaneously observed at microwaves and hard X rays in a solar burst (1983)
    [s.l.] : Nature Publishing Group
    Nature 302 (1983), S. 317-319 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] A solar sub-flare occurred on 4 November 1981 at 18 h 28 min 20 s UT. The associated radio and X-ray bursts, shown in compressed time scale in Fig. la, b, reveal that the correlation of the major burst time structures is poor among the three microwave frequencies, and between microwaves and hard X ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/302317a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Solar burst with millimetre-wave emission at high frequency only (1985)
    [s.l.] : Nature Publishing Group
    Nature 313 (1985), S. 380-382 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Past observations at centimetre-millimetre wavelengths indicate that certain bursts can display turnover frequencies which are higher than 30 GHz (l 〈 10 mm)4-9. One very large burst exhibited a spectral 'flattening' in the range 30-71 GHz (refs 4, 5), which was also found for a few other ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/313380a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Low-level decimetric (1.6 GHz) solar burst activity (1987)
    Springer
    Solar physics 111 (1987), S. 189-199 
    Details
    ISSN: 1573-093X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Observations of solar bursts at 1.6 GHz were carried out in the month of July 1985 for about two weeks. Five intervals of solar burst activity, each one lasting for a couple of minutes, were observed. Predominantly, two classes of fast bursts were observed: viz: ‘spike’ and ‘blips’. However, some of these bursts were two orders of magnitude less intense than those reported earlier. Low-level blips have typical duration ∼ 350 ms, excitation time ∼ 200 ± 25 ms, decay time ∼ 130 ± 25 ms and a low degree of circular polarization of about 15%. Detailed investigations of decay times of the blips have been carried out in terms of collisional damping and Landau damping. Observed decay times of the blips seem to favour the hypothesis of collisional damping. This investigation suggests that blips probably originate at second harmonic by beam plasma interaction as that of metric type III bursts. Also, low-level ms-spikes with the half power duration in the range of 5 to 20 ms suggest that source sizes be smaller than 50 km if the process of emission is electron-cyclotron maser.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00145452
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    An eruptive prominence and associated cm-mm emission outside the solar limb (1988)
    Springer
    Solar physics 116 (1988), S. 83-89 
    Details
    ISSN: 1573-093X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We present radio maps at 22 and 44 GHz which show the emission before and after the eruption of a quiescent prominence located at the west limb. The observed radiation following the eruption is not consistent with thermal bremsstrahlung mechanism. It can be interpreted as due to gyrosynchrotron emission of nonthermal electrons. Our observations appear to be similar to the microwave radiation observed in post-flare loops; this radiation is due to nonthermal electrons trapped in the closed magnetic structures formed after the prominence eruption.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00171716
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A multibeam antenna for solar MM-wave burst observations with high spatial and temporal resolution (1992)
    Springer
    Solar physics 142 (1992), S. 157-170 
    Details
    ISSN: 1573-093X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In this paper a new method for the determination of the position of microwave burst sources on the Sun, its implementation and first observational results, are presented. The 13.7 m antenna at Itapetinga with a five-channel receiver operating at 48 GHz and with a time resolution of 1 ms is used. Five horn antennas clustered around the focus of the Cassegrain reflector provide 5 beams diverging by about 2′. This configuration allows the observation of different parts of an active region and the determination of the center of the burst position with an accuracy of 5″ to 20″ depending on the angular distance relative to the antenna axis. The field of view is ≈ 2′ by ≈ 4′. The time resolution of 1 ms is suitable to search for fast structures at 48 GHz. A total bandwidth of 400 MHz is used in order to achieve a sensitivity of 0.04 s.f.u. sufficient for the detection of weak bursts. First observational results of the flare on May 11, 1991 show a well-located source position during all stages.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00156639
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Interpretation of temporal features in an unusual X-ray and microwave burst (1986)
    Springer
    Solar physics 104 (1986), S. 191-198 
    Details
    ISSN: 1573-093X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Observations are briefly discussed of an event in which microwave and hard X-ray emissions were not correlated in the accepted way. Two impulsive peaks of roughly equal intensity were observed at three different microwave frequencies. The hard X-ray peaks accompanying these, however, differ in intensity by almost two orders of magnitude. Various possible interpretations of this burst are discussed, in the context of familiar models of these emissions. The most likely explanation is that the electron spectrum in the first burst has a break at about 350 keV. General implications for interpretation of X-rays and microwaves are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00159962
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Comments on fast pulses in mm-wave bursts (1986)
    Springer
    Solar physics 104 (1986), S. 253-256 
    Details
    ISSN: 1573-093X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The first observation of a solar burst with millisecond time resolution at λ = 3.3 mm was obtained on 21 May, 1984. The time-scale of the millimetric pulses durations was of about 60 ms. The possible strong correlation between pulsed emission at 3.3 mm and hard X-rays is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00159970
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Short-period pulsations observed simultaneously by X-ray and radio waves (1983)
    Springer
    Solar physics 86 (1983), S. 237-238 
    Details
    ISSN: 1573-093X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract From simultaneous high-time-resolution observations of solar X-rays from Hinotori and the millimeter waves at Itapetinga Radio Observatory in Brazil during a solar flare on November 4, 1981 at 1827 UT, short period (∼ 300 ms) pulsations have been detected in five time intervals of 2 s each. Both a cross-correlation analysis between X-rays and microwaves and a Fourier analysis were made to verify the significance of the quasi-periodic pulsations. The cross-correlation is significant but the pulsations could not be periodic oscillation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00157194
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Time delays in solar bursts measured in the mm-cm range of wavelengths (1982)
    Springer
    Solar physics 81 (1982), S. 159-172 
    Details
    ISSN: 1573-093X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Various solar bursts have been analysed with high sensitivity (0.03 sfu, rms) and high-time resolution (1 ms) at two frequencies in the millimeter wave range (22 GHz and 44 GHz), and with moderate time resolution (100 ms) by a patrol telescope at a frequency in the microwave range (7 GHz). It was found that, in most cases, burst maximum emission is not coincident in time at those frequencies. Preceding maximum emission can be either at the higher or at the lower frequency. Time delays ranged from about 3 s to near coincidence, defined within 10 ms. Some complex bursts presented all kinds of delays among different time structures, and sometimes nearly uncorrelated time structures. Large time delays favour the association of the dynamic effects to shock wave speeds. Directional particle acceleration in complex magnetic configuration could be considered to explain the variety of the dynamic effects. Fastest burst rise times observed, less than 50 ms at 44 GHz and at 22 GHz, might be associated to limiting formation times of emission sources combined with various absorption mechanisms at the source and surrounding plasma.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00151987
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...