Sentences with phrase «cosmogenic radionuclide»

We discuss the East Asian naked - eye sunspot observations, the telescopic solar observations, the fraction of sunspot active days, the latitudinal extent of sunspot positions, auroral sightings at high latitudes, cosmogenic radionuclide data as well as solar eclipse observations for that period.

An alternative recorder for past geomagnetic field changes are cosmogenic radionuclide production rates, which are modulated by variations of both the solar magnetic field strength and the geomagnetic field intensity.

Therefore, cosmogenic radionuclide records can provide independent information about past dipole moment changes, but it is necessary to eliminate the influence of solar variations.

The cosmogenic radionuclide records have been low - pass filtered by a rectangular function in the frequency domain with different cut - off frequencies in order to minimise the solar influence and to investigate the time scales on which we see common changes in the radionuclide production rates and the geomagnetic field intensity reconstructions.

The variations of solar activity over long time intervals using a solar activity reconstruction based on the cosmogenic radionuclide 10Be measured in polar ice cores are studied.

The somewhat contradictory results for the similarity of radionuclide - based dipole reconstructions and geomagnetic field models on these time scales point out that geomagnetic field models have to be improved further before they can provide a truly robust means to eliminate the influence of geomagnetic variability in cosmogenic radionuclide production studies.

Dipole intensity estimates from cosmogenic radionuclide production records, with suitable filtering to minimise the solar influence, have also been included in the comparison to provide independent information about variations in the strength of the geomagnetic field.

Cosmogenic radionuclide production rates are also influence by the geomagnetic field.

Kovaltsov, G. A. & Usoskin, I. G. Occurrence probability of large solar energetic particle events: assessment from data on cosmogenic radionuclides in lunar rocks.

A test with the potential to be particularly informative would assess NWA 7325's levels of «cosmogenic radionuclides,» unstable atoms generated by exposure to cosmic radiation.

Cosmogenic radionuclides such as 10Be are proxies for this influence and for the poloidal field variations.

The model's validity is also tested using the cosmogenic radionuclides 14C and 10Be stored in terrestrial archives.

The cosmogenic radionuclides confirm the existence of these and other longer periodicities (e.g., 208 year DeVries or Suess cycle, 2300 year Hallstatt cycle, and others) and also the present relatively high level of solar activity, although there is some controversy as to how unusually high it really is [Muscheler et al., 2007; Usoskin et al., 2004; Steinhilber et al., 2008].

It is well known that the Sun plays the fundamental role as our energy source... To date, the only proxy providing information about the solar variability on millennial time scales are cosmogenic radionuclides stored in natural archives such as ice cores.

F. Steinhilber, J. A. Abreu, J. Beer, and K. G. McCracken (2010), Interplanetary magnetic field during the past 9300 years inferred from cosmogenic radionuclides, J. Geophys.

Reconstructions of the geomagnetic field in the past represent a useful tool not only to investigate the geodynamo process, but also to estimate the effect of geomagnetic shielding for any studies on cosmogenic radionuclides and galactic cosmic rays.

Here we use a 9400 year solar activity reconstruction derived from cosmogenic radionuclides to test this hypothesis.

Not exact matches

Volker Doormann says: July 27, 2011 at 2:38 pm http://adsabs.harvard.edu/abs/2010JGRA..11501104S We have reconstructed the interplanetary magnetic field (IMF), its radial component, and the open solar magnetic flux using the solar modulation potential derived from cosmogenic 10Be radionuclide data for a period covering the past 9300 years.

http://adsabs.harvard.edu/abs/2010JGRA..11501104S «We have reconstructed the interplanetary magnetic field (IMF), its radial component, and the open solar magnetic flux using the solar modulation potential derived from cosmogenic 10Be radionuclide data for a period covering the past 9300 years.