STUDI GELOMBANG ULF: KORELASI PULSA MAGNET Pc3 DENGAN KECEPATAN ANGIN SURYA DAN MEDAN MAGNET ANTARPLANET

Energy for the Earth’s magnetospheric processes is provided by solar wind. Pc3 magnetic pulsation is one of geomagnetic ULF wave. Pc3 magnetic pulsation has been studied to understand the dynamic of magnetosphere. Geomagnetic pulsations are quasi-sinusoide variations in the Earth’s magnetic field in the period range of 10-45 seconds. The magnitude of these pulsations ranges from fraction of a nT (nano Tesla) to several nT. These pulsations can be observed in a number of ways such as applied of ground based magnetometer. We used the magnetometer data of Manado, Parepare, and Kupang stations to studied the effect of the solar wind and interplanetary magnetic field on these pulsations. To extract Pc3 magnetic pulsations we applied second order of Butterworth filter and using Hamming windowing. The result showed that Pc3 magnetic pulsation have correlation with increasing solar wind velocity and interplanetary magnetic field-IMF, it is mean that solar wind controls Pc3 magnetic pulsations occurrence. AbstrakAngin surya merupakan sumber energi bagi proses-proses fisis yang terjadi di magnetosfer Bumi. Untuk dapat memahami dinamika di magnetosfer Bumi dapat di tinjau dari gelombang ULF salah satunya pulsa magnet Pc3. Pulsa magnet Pc3 merupakan variasi quasi-sinusoide pada medan magnet Bumi dalam rentang periode 10 – 45 detik. Pulsa magnet Pc3 umumnya memiliki amplitudo rendah dengan rentang nT (nano Tesla). Terdapat beberapa cara yang dapat dilakukan untuk mengamati pulsa magnet Pc3 diantaranya dengan menggunakan magnetometer landas Bumi. Dalam makalah ini kami menggunakan data pengamatan magnetometer stasiun Kupang, Manado, dan Parepare untuk mempelajari hubungan pulsa magnet Pc3 terkait dengan angin surya dan medan magnet antarplanet. Pulsa magnet Pc3 diekstrak dari data variasi medan magnet dengan menggunakan Butterworth Filter dan Hamming windowing. Hasil yang diperoleh menunjukkan bahwa pulsa magnet Pc3 memiliki korelasi dengan peningkatan kecepatan angin surya dan medan magnet antarplanet. Hal ini mengindikasikan bahwa angin surya merupakan salah satu sumber yang mengontrol perubahan yang terjadi pada pulsa magnet Pc3.

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Effect of geomagnetic activity, solar wind and parameters of interplanetary magnetic field on regularities in intermittency of Pi2 geomagnetic pulsations

Solnechno-Zemnaya Fizika ◽

10.12737/11551 ◽

2015 ◽

Vol 1 (3) ◽

pp. 11-20 ◽

Cited By ~ 3

Author(s):

Надежда Куражковская ◽

Nadezhda Kurazhkovskaya ◽

Борис Клайн ◽

Boris Klain

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Interplanetary Magnetic Field ◽

Geomagnetic Activity ◽

Dynamic Pressure ◽

Cumulative Distribution ◽

Qualitative Assessment ◽

Geomagnetic Pulsations ◽

Magnetospheric Substorms ◽

Pi2 Pulsations

We present the results of investigation of the influence of geomagnetic activity, solar wind and parameters of the interplanetary magnetic field (IMF) on properties of the intermittency of midlatitude burst series of Pi2 geomagnetic pulsations observed during magnetospheric substorms on the nightside (substorm Pi2) and in the absence of these phenomena (nonsub-storm Pi2). We considered the index α as a main characteristic of intermittency of substorm and nonsubstorm Pi2 pulsations. The index α characterizes the slope of the cumulative distribution function of Pi2 burst amplitudes. The study indicated that the value and dynamics of the index α varies depending on the planetary geomagnetic activity, auroral activity and the intensity of magnetospheric ring currents. In addition, the forms of dependences of the index α on the density n, velocity V, dynamic pressure Pd of the solar wind and IMF Bx-component are different. The behavior of the index α depending on the module of B, By- and Bz-components is similar. We found some critical values of V, Pd, B, By- and Bz-components, after reaching of which the turbulence of the magnetotail plasma during substorm development is decreased. The revealed patterns of the intermittency of Pi2 pulsations can be used for qualitative assessment of turbulence level in the magnetotail plasma depending on changing interplanetary conditions.

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Even moderate geomagnetic pulsations can cause fluctuations of <i>fo</i>F2 frequency of the auroral ionosphere

Annales Geophysicae ◽

10.5194/angeo-39-549-2021 ◽

2021 ◽

Vol 39 (3) ◽

pp. 549-562

Author(s):

Nadezda Yagova ◽

Alexander Kozlovsky ◽

Evgeny Fedorov ◽

Olga Kozyreva

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Critical Frequency ◽

Solar Wind Speed ◽

Weather Conditions ◽

Wind Pressure ◽

Geomagnetic Pulsations ◽

Radio Waves ◽

Magnetic Pulsations ◽

Solar Wind Pressure

Abstract. The ionosonde at the Sodankylä Geophysical Observatory (SOD; 67∘ N, 27∘ E; Finland) routinely performs vertical sounding once per minute which enables the study of fast ionospheric variations at a frequency of the long-period geomagnetic pulsations Pc5–6/Pi3 (1–5 mHz). Using the ionosonde data from April 2014–December 2015 and colocated geomagnetic measurements, we have investigated a correspondence between the magnetic field pulsations and variations of the critical frequency of radio waves reflected from the ionospheric F2 layer (foF2). For this study, we have developed a technique for automated retrieval of the critical frequency of the F2 layer from ionograms. As a rule, the Pc5–6/Pi3 frequency band fluctuations in foF2 were observed at daytime during quiet or moderately disturbed space weather conditions. In most cases (about 80 %), the coherence between the foF2 variations and geomagnetic pulsations was low. However in some cases (specified as “coherent”) the coherence was as large as γ2≥0.5. The following conditions are favorable for the occurrence of coherent cases: enhanced auroral activity (6 h maximal auroral electrojet (AE) ≥800 nT), high solar wind speed (V>600 km/s), fluctuating solar wind pressure and northward interplanetary magnetic field. In the cases when the coherence was higher at shorter periods of oscillations, the magnetic pulsations demonstrated features typical for the Alfvén field line resonance.

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H-Cmes and Ii-Type Radio Bursts Related Intense Geomagnetic Storms in Relation With Interplanetary Magnetic Field and Solar Wind Disturbances

International Journal of Scientific Research ◽

10.15373/22778179/oct2013/123 ◽

2012 ◽

Vol 2 (10) ◽

pp. 1-3 ◽

Cited By ~ 9

Author(s):

Praveen Kumar Gupta ◽

◽

Puspraj Singh Puspraj Singh ◽

P. K. Chamadia P. K. Chamadia

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Interplanetary Magnetic Field ◽

Geomagnetic Storms ◽

Radio Bursts ◽

Solar Wind Disturbances

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INFLUENCE OF THE INTERPLANETARY MAGNETIC FIELD ORIENTATION ON NORTH-SOUTHERN ASYMMETRY OF ULF WAVE PACKETS IN THE POLAR CAPS

Геофизические исследования ◽

10.21455/gr2019.2-2 ◽

2019 ◽

Keyword(s):

Magnetic Field ◽

Interplanetary Magnetic Field ◽

Wave Packets ◽

Field Orientation ◽

Magnetic Field Orientation ◽

Ulf Wave ◽

Polar Caps

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Interplanetary magnetic field control of Saturn's polar cusp aurora

Annales Geophysicae ◽

10.5194/angeo-23-1405-2005 ◽

2005 ◽

Vol 23 (4) ◽

pp. 1405-1431 ◽

Cited By ~ 48

Author(s):

E. J. Bunce ◽

S. W. H. Cowley ◽

S. E. Milan

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Interplanetary Magnetic Field ◽

Field Line ◽

High Latitude ◽

Closed Field ◽

Vortical Flows ◽

Dayside Magnetopause ◽

Closed Field Line ◽

Lobe Reconnection

Abstract. Dayside UV emissions in Saturn's polar ionosphere have been suggested to be the first observational evidence of the kronian "cusp" (Gérard et al., 2004). The emission has two distinct states. The first is a bright arc-like feature located in the pre-noon sector, and the second is a more diffuse "spot" of aurora which lies poleward of the general location of the main auroral oval, which may be related to different upstream interplanetary magnetic field (IMF) orientations. Here we take up the suggestion that these emissions correspond to the cusp. However, direct precipitation of electrons in the cusp regions is not capable of producing significant UV aurora. We have therefore investigated the possibility that the observed UV emissions are associated with reconnection occurring at the dayside magnetopause, possibly pulsed, akin to flux transfer events seen at the Earth. We devise a conceptual model of pulsed reconnection at the low-latitude dayside magnetopause for the case of northwards IMF which will give rise to pulsed twin-vortical flows in the magnetosphere and ionosphere in the vicinity of the open-closed field-line boundary, and hence to bi-polar field-aligned currents centred in the vortical flows. During intervals of high-latitude lobe reconnection for southward IMF, we also expect to have pulsed twin-vortical flows and corresponding bi-polar field-aligned currents. The vortical flows in this case, however, are displaced poleward of the open-closed field line boundary, and are reversed in sense, such that the field-aligned currents are also reversed. For both cases of northward and southward IMF we have also for the first time included the effects associated with the IMF By effect. We also include the modulation introduced by the structured nature of the solar wind and IMF at Saturn's orbit by developing "slow" and "fast" flow models corresponding to intermediate and high strength IMF respectively. We then consider the conditions under which the plasma populations appropriate to either sub-solar reconnection or high-latitude lobe reconnection can carry the currents indicated. We have estimated the field-aligned voltages required, the resulting precipitating particle energy fluxes, and the consequent auroral output. Overall our model of pulsed reconnection under conditions of northwards and southwards IMF, and for varying orientations of IMF By, is found to produce a range of UV emission intensities and geometries which is in good agreement with the data presented by Gérard et al. (2004). The recent HST-Cassini solar wind campaign provides a unique opportunity to test the theoretical ideas presented here.

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