scholarly journals On Cosmic Rays, IP Structures and Geospace Consequences During WHI

2009 ◽  
Vol 5 (H15) ◽  
pp. 488-490
Author(s):  
A. Dal Lago ◽  
F. L. Guarnieri ◽  
M. R. da Silva ◽  
W. D. Gonzalez ◽  
C. R. Braga ◽  
...  
Keyword(s):  
High Speed ◽  
Interplanetary Space ◽  
Cosmic Ray ◽  
Corotating Interaction Regions ◽  
Near Earth Space ◽  
Long Duration ◽  
Minimum Solar Activity ◽  
Interaction Regions ◽  
Muon Detection ◽  
Whole Heliosphere Interval

AbstractThis work presents some observations during the period of the Whole Heliosphere Interval (WHI) of the effects of interplanetary (IP) structures on the near-Earth space using three sets of observations: magnetic field and plasma from the Advanced Composition Explorer (ACE) satellite, ground-based cosmic ray data from the Global Muon Detection Network (GMDN) and geomagnetic indices (Disturbance storm-time, Dst, and auroral electrojet index, AE). Since WHI was near minimum solar activity, high speed streams and corotating interaction regions (CIRs) were the dominant structures observed in the interplanetary space surrounding Earth. Very pronounced geomagnetic effects are shown to be correlated to CIRs, especially because they can cause the so-called High-Intensity Long-Duration Continuous AE Activity (HILDCAAs) - Tsurutani and Gonzalez (1987). At least a few high speed streams can be identified during the period of WHI. The focus here is to characterize these IP structures and their geospace consequences.

Solar wind temperature–velocity relationship over the last five solar cycles and Forbush decreases associated with different types of interplanetary disturbance

2020 ◽  
Vol 500 (3) ◽  
pp. 2786-2797
Author(s):  
A A Melkumyan ◽  
A V Belov ◽  
M A Abunina ◽  
A A Abunin ◽  
E A Eroshenko ◽  
...  
Keyword(s):  
Solar Wind ◽  
High Speed ◽  
Coronal Holes ◽  
Cosmic Ray ◽  
Magnetic Clouds ◽  
Solar Cycles ◽  
Forbush Decreases ◽  
Proton Temperature ◽  
Interaction Regions ◽  
Interplanetary Disturbance

ABSTRACT The behaviour of the solar wind (SW) proton temperature and velocity and their relationship during Forbush decreases (FDs) associated with various types of solar source – coronal mass ejections (CMEs) and coronal holes (CHs) – have been studied. Analysis of cosmic ray variations, SW temperature, velocity, density, plasma beta, and magnetic field (from 1965–2019) is carried out using three databases: the OMNI database, Variations of Cosmic Rays database (IZMIRAN) and Forbush Effects & Interplanetary Disturbances database (IZMIRAN). Comparison of the observed SW temperature (T) and velocity (V) for the undisturbed SW allows us to derive a formula for the expected SW temperature (Texp, the temperature given by a T–V formula, if V is the observed SW speed). The results reveal a power-law T–V dependence with a steeper slope for low speeds (V < 425 km s−1, exponent = 3.29 ± 0.02) and flatter slope for high speeds (V > 425 km s−1, exponent = 2.25 ± 0.02). A study of changes in the T–V dependence over the last five solar cycles finds that this dependence varies with solar activity. The calculated temperature index KT = T/Texp can be used as an indicator of interplanetary and solar sources of FDs. It usually has abnormally large values in interaction regions of different-speed SW streams and abnormally low values inside magnetic clouds (MCs). The results obtained help us to identify the different kinds of interplanetary disturbance: interplanetary CMEs, sheaths, MCs, corotating interaction regions, high-speed streams from CHs, and mixed events.

Cosmic-Ray Transport in Heliospheric Magnetic Structures. II. Modeling Particle Transport through Corotating Interaction Regions

2017 ◽  
Vol 837 (1) ◽  
pp. 37 ◽  
Author(s):  
Andreas Kopp ◽  
Tobias Wiengarten ◽  
Horst Fichtner ◽  
Frederic Effenberger ◽  
Patrick Kühl ◽  
...  
Keyword(s):  
Particle Transport ◽  
Cosmic Ray ◽  
Corotating Interaction Regions ◽  
Magnetic Structures ◽  
Interaction Regions

scholarly journals The Sources of Major Heliospheric Disturbances

1986 ◽  
Vol 7 ◽  
pp. 749-753
Author(s):  
A. Hewish
Keyword(s):  
Solar Flares ◽  
High Speed ◽  
Solar Maximum ◽  
Coronal Holes ◽  
Interplanetary Shocks ◽  
Spherical Shells ◽  
Corotating Interaction Regions ◽  
Speed Solar Wind ◽  
Interaction Regions ◽  
High Speed Solar Wind

AbstractObservations of interplanetary scintillation on about 900 sources made with the 3.6 hectare array at Cambridge have been used to map, and to track, 96 heliospheric transients during August 1978–September 1979. This sample included most of the interplanetary shocks recorded by near-Earth spacecraft in the same period.Some corotating interaction regions were observed but the most frequent disturbances were “erupting streams” in which spherical shells of enhanced density were driven by the birth of high-speed solar wind streams which persisted for several days. Although these transients were of the type traditionally associated with solar flares or disappearing filaments they were not caused by such processes. Back-projection to the Sun indicated that the sources were always associated with coronal holes. It is concluded that the sources of the most energetic interplanetary transients are mid-latitude coronal holes which, near solar maximum, produce sporadic high-speed streams lasting several days, in contrast to the more stable flows typical of the declining phase of the solar cycle.

scholarly journals Cosmic ray modulation by corotating interaction regions

2008 ◽  
Vol 4 (S257) ◽  
pp. 425-427 ◽  
Author(s):  
Jaša Čalogović ◽  
Bojan Vršnak ◽  
Manuela Temmer ◽  
Astrid M. Veronig
Keyword(s):  
Solar Wind ◽  
Time Lag ◽  
Cosmic Ray ◽  
Central Meridian ◽  
Corotating Interaction Regions ◽  
Cosmic Ray Modulation ◽  
Cross Correlation Analysis ◽  
Interaction Regions ◽  
The Relationship

AbstractWe analyzed the relationship between the ground-based modulation of cosmic rays (CR) and corotating interaction regions (CIRs). Daily averaged data from 8 different neutron monitor (NM) stations were used, covering rigidities from Rc = 0 − 12.91 GeV. The in situ solar wind data were taken from the Advanced Composition Explorer (ACE) database, whereas the coronal hole (CH) areas were derived from the Solar X-Ray Imager onboard GOES-12. For the analysis we have chosen a period in the declining phase of solar cycle 23, covering the period 25 January–5 May 2005. During the CIR periods CR decreased typically from 0.5% to 2%. A cross-correlation analysis showed a distinct anti-correlation between the magnetic field and CR, with the correlation coefficient (r) ranging from −0.31 to −0.38 (mean: −0.36) and with the CR time delay of 2 to 3 days. Similar anti-correlations were found for the solar wind density and velocity characterized by the CR time lag of 4 and 1 day, respectively. The relationship was also established between the CR modulation and the area of the CIR-related CH with the CR time lag of 5 days after the central-meridian passage of CH.

The influence of corotating interaction regions and high speed streams on electrons in the martian magnetosheath and ionosphere

2013 ◽  
Author(s):  
Heather A. Elliott ◽  
Rudy A. Frahm ◽  
James R. Sharber ◽  
Timothy A. Howard ◽  
Dusan Odstrčil ◽  
...  
Keyword(s):  
High Speed ◽  
Corotating Interaction Regions ◽  
Interaction Regions

scholarly journals Global geomagnetic responses to the IMF <i>B</i><sub>z</sub> fluctuations during the September/October 2003 high-speed stream intervals

2017 ◽  
Vol 35 (4) ◽  
pp. 853-868 ◽  
Author(s):  
Ezequiel Echer ◽  
Axel Korth ◽  
Mauricio José Alves Bolzan ◽  
Reinhard Hans Walter Friedel
Keyword(s):  
Solar Wind ◽  
High Speed ◽  
Auroral Zone ◽  
Corotating Interaction Regions ◽  
Ae Index ◽  
Speed Solar Wind ◽  
Interaction Regions ◽  
Cross Wavelet Analysis ◽  
Cross Wavelet ◽  
High Speed Solar Wind

Abstract. In this paper, we follow the coupling from the solar wind to the Earth's magnetotail, geosynchronous orbit, auroral zone and to the ground, during periods of Alfvénic fluctuations in high-speed solar wind streams (HSSs) and their corotating interaction regions (CIRs). We employ cross-wavelet analysis of magnetic field, particle flux and auroral electrojet (AE) index data for the HSSs of September and October 2003. Our results show a remarkably consistent periodic response among all of these regions and across multiple substorm indicators, indicating a possible driven substorm response of the global magnetosphere to the solar wind interplanetary structures. Across the seven intervals studied we find a range of periodic responses from 1.8 to 3.1 h, which is consistent with the 2.75 h peak of the Borovsky et al. (1993) statistical study of inter-substorm periods.

Sign in / Sign up

Export Citation Format

Share Document