【摘 要】
：
Forbush decrease (FD),discovered by Scott E.Forbush about 80 years ago,is referred to as the non-repetitive short-term depression in Galactic cosmic ray (GCR) flux,presumed to be associated with large-scale perturbations in solar wind and interplanetary m
【机 构】
：
Department of Physics and Astronomy,University of Nigeria,Nsukka 400001,Nigeria;Department of Indust
论文部分内容阅读
Forbush decrease (FD),discovered by Scott E.Forbush about 80 years ago,is referred to as the non-repetitive short-term depression in Galactic cosmic ray (GCR) flux,presumed to be associated with large-scale perturbations in solar wind and interplanetary magnetic field (IMF).It is the most spectacular variability in the GCR intensity which appears to be the compass for investigators seeking solar-terrestrial relationships.The method of selection and validation of FD events is very important to cosmic ray (CR)scientists.We have deployed new computer software to determine the amplitude and timing of FDs from daily-averaged CR data at Oulu Neutron Monitor station.The code selected 230 FDs between 1998 and 2002.In an attempt to validate the new FD automated catalog,the relationship between the amplitude of FDs,and IMF,solar wind speed (SWS) and geomagnetic storm indices (Dst,kp,ap) is tested here.A two-dimensional regression analysis indicates significant linear relationship between large FDs (CR(％)≤-3) and solar wind data and geomagnetic storm indices in the present sample.The implications of the relationship among these parameters are discussed.
其他文献
In the popular ΛCDM model,the cosmic microwave background radiation (CMBR) is thought to be the remnant of the early hot universe.An important precondition of this interpretation of CMBR is:after the last scattering surface formed,the high temperature ion
We investigate relations in the emission properties as revealed by drifting subpulses detected at different observing frequencies based on the method that incorporates the rotating carousels in pulsar magnetospheres of multiple emission states.An emission
PSR J1946 + 3417 is a millisecond pulsar (MSP) with a spin period P ≈ 3.17 ms.Harbored in a binary with an orbital period Pb ≈ 27 days,the MSP is accompanied by a white dwarf (WD).The masses of the MSP and the WD were determined to be 1.83 M⊙ and 0.266 M⊙
Spectrum denoising is an important procedure for large-scale spectroscopical surveys.This work proposes a novel stellar spectrum denoising method based on deep Bayesian modeling.The construction of our model includes a prior distribution for each stellar
Ellerman bombs (EBs) and ultraviolet (UV) bursts are common brightening phenomena,which are usually generated in the low solar atmosphere of emerging flux regions.In this paper,we have investigated the emergence of an initial un-twisted magnetic flux rope
Flat-field reflects the non-uniformity of the photometric response at the focal plane of an instrument,which uses digital image sensors,such as Charge Coupled Device (CCD) and Complementary Metal-Oxide-Semiconductor (CMOS).This non-uniformity must be corr
PolarLight is a space-borne X-ray polarimeter that measures the X-ray polarization via electron tracking in an ionization chamber.It is a collimated instrument and thus suffers from the background on the whole detector plane.The majority of background eve
This paper presents the results of Hα imaging of 169 galaxies randomly selected from the α.40-SDSS catalog.The sample has excluded all low surface brightness galaxies (LSBGs) whose central surface brightness in B band (μ0(B)) fainter than 22.5 mag arcsec-
The lower solar atmosphere is a gravitationally stratified layer of partially ionized plasma.We calculate the electric resistivity in the solar photosphere and chromosphere,which is the key parameter that controls the rate of magnetic reconnection in a Sw
Multi-band photometry and light curve analysis for two newly recognized contact binary systems,TYC 6995-813-1 and NSVS 13602901,are presented.Both were found to be of extreme low mass ratios 0.11 and 0.17,respectively.The secondary components of both syst