Assessment of the Earth’s cold plasmatrough modeling by using Van Allen Probes/EMFISIS and Arase/PWE electron density data

Author(s):  
E. Botek ◽  
V. Pierrard ◽  
F. Darrouzet
2016 ◽  
Vol 12 (S328) ◽  
pp. 230-232
Author(s):  
Adriane M. de Souza ◽  
Ezequiel Echer ◽  
Mauricio J. A. Bolzam ◽  
Markus Fränz

AbstractWavelet analysis was employed to identify the major frequencies of low-frequency waves present in the Martian magnetosheath. The Morlet wavelet transform was selected and applied to the electron density data, obtained from the Analyzer of Space Plasmas and Energetic Atoms experiment (ASPERA-3), onboard the Mars Express (MEX) spacecraft. We have selected magnetosheath crossings and analyzed electron density data. From a preliminary study of 502 magnetosheath crossings (observed during the year of 2005), we have found 1409 periods between 0.005 and 0.06Hz. The major frequencies observed were in the range 0.005-0.02 Hz with 58.5% of the 1409 frequencies identified.


2019 ◽  
Author(s):  
Xiuying Wang ◽  
Dehe Yang ◽  
Dapeng Liu ◽  
Wei Chu

Abstract. Many studies have revealed the stratification phenomenon of the topside ionospheric F2 layer using ground-based or satellite-based ionograms, which can show direct signs of this phenomenon. However, it is difficult to identify this phenomenon using the satellite-based in situ electron density data. Therefore, a statistical method, using the shuffle resampling skill, is adopted in this paper. For the first time, in situ electron density data, recorded by the same Langmuir probe onboard the Demeter satellite at different altitudes, are analyzed and a possible stratification phenomenon is identified using the proposed method. Our results show that the nighttime stratification, possibly a permanent phenomenon, can cover most longitudes near the geomagnetic equator, which is not found from the daytime data. The arch-like nighttime stratification decreases slowly on the summer hemisphere and thus extends a larger latitudinal distance from the geomagnetic equator. All results, obtained by the proposed method, indicate that the stratification phenomenon is more complex than what has previously been found. The proposed method thus is an effective one, which can also be used on similar studies of comparing fluctuated data.


2019 ◽  
Vol 37 (4) ◽  
pp. 645-655 ◽  
Author(s):  
Xiuying Wang ◽  
Dehe Yang ◽  
Dapeng Liu ◽  
Wei Chu

Abstract. Many studies have revealed the stratification phenomenon of the topside ionospheric F2 layer using ground-based or satellite-based ionograms, which can show direct signs of this phenomenon. However, it is difficult to identify this phenomenon using the satellite-based in situ electron density data. Therefore, a statistical method, using the shuffle resampling skill, is adopted in this paper. For the first time, in situ electron density data, recorded by the same Langmuir probe aboard the DEMETER (Detection of Electro-Magnetic Emission Transmitted from Earthquake Regions) satellite at different altitudes, are analyzed, and a possible stratification phenomenon is identified using the proposed method. Our results show that the nighttime stratification, possibly a permanent phenomenon, can cover most longitudes near the geomagnetic equator, which is not found from the daytime data. The arch-like nighttime stratification decreases slowly on the summer hemisphere and thus extends a larger latitudinal distance from the geomagnetic equator. All results, obtained by the proposed method, indicate that the stratification phenomenon is more complex than what has previously been found. The proposed method is thus an effective one, which can also be used in similar studies of comparing fluctuated data.


Radio Science ◽  
2014 ◽  
Vol 49 (8) ◽  
pp. 680-688 ◽  
Author(s):  
C. L. Rino ◽  
C. S. Carrano ◽  
Patrick Roddy

Atmosphere ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 371 ◽  
Author(s):  
Angelo De Santis ◽  
Dedalo Marchetti ◽  
Luca Spogli ◽  
Gianfranco Cianchini ◽  
F. Javier Pavón-Carrasco ◽  
...  

We analyse Swarm satellite magnetic field and electron density data one month before and one month after 12 strong earthquakes that have occurred in the first 2.5 years of Swarm satellite mission lifetime in the Mediterranean region (magnitude M6.1+) or in the rest of the world (M6.7+). The search for anomalies was limited to the area centred at each earthquake epicentre and bounded by a circle that scales with magnitude according to the Dobrovolsky’s radius. We define the magnetic and electron density anomalies statistically in terms of specific thresholds with respect to the same statistical quantity along the whole residual satellite track (|geomagnetic latitude| ≤ 50°, quiet geomagnetic conditions). Once normalized by the analysed satellite tracks, the anomalies associated to all earthquakes resemble a linear dependence with earthquake magnitude, so supporting the statistical correlation with earthquakes and excluding a relationship by chance.


2016 ◽  
Vol 58 (6) ◽  
pp. 856-866 ◽  
Author(s):  
T. Gerzen ◽  
J. Feltens ◽  
N. Jakowski ◽  
I. Galkin ◽  
B. Reinisch ◽  
...  

2011 ◽  
Vol 11 (2) ◽  
pp. 597-611 ◽  
Author(s):  
A. M. Hasbi ◽  
M. A. Mohd Ali ◽  
N. Misran

Abstract. The paper investigates the ionospheric variations before some large earthquakes that occurred during 2004–2007 in Sumatra using GPS and CHAMP data. The TEC shows the occurrence of positive and negative anomalies detected within a few hours to 6 days before the earthquakes. These anomalies mostly occur during the daytime hours between 4 and 17 LT. The TEC anomalies are mostly consistent with the CHAMP satellite electron density data. The electron density analysis over the 28 March 2005 earthquake epicenter shows that an equatorial anomaly modification took place a few days before the event. The modification took shape in the form of crest amplification during the daytime. The comparison between the TEC and electron density measurements during very quiet geomagnetic conditions is shown to be a useful indicator of a forthcoming earthquake.


2008 ◽  
Vol 47 (3) ◽  
Author(s):  
F. C. De Meneses ◽  
P. Muralikrishna ◽  
B. R. Clemesha
Keyword(s):  

Fotómetros y sensores para medidas de densidad electrónica a bordo de cohetes de sondeo brasileños Sonda III fueron lanzados desde Natal (5.8º S, 35.2º W), Brasil. El primero en 11 de Diciembre de 1985 (20:30 hora local) y el otro en 31 de Octubre de 1986 (22:59 hora local). La carga científica consistió de fotómetros para medir emisiones de oxígeno atómico OI 557.7 nm (línea verde) y OI 630 nm (línea roja) en la ionosfera nocturna, dispuestos paralelamente al eje de giro del cohete, y dos sondas de densidad electrónica: una sonda de Langmuir y la otra tipo capacitiva de alta frecuencia, utilizadas para medir la densidad electrónica ionosférica y la presencia de fluctuaciones espaciales. Los valores de densidad electrónica medidos desde esos vuelos de cohetes y otros parámetros obtenidos en los modelos IRI-2001 y MSIS-E 90 han sido utilizados para obtener perfiles de tasa de emisión volumétrica de los oxígenos atómicos OI 557.7 nm y OI 630 nm. Esos datos son comparados con perfiles de altitud obtenidos a partir de los datos de los fotómetros. Tomando como base este estudio comparativo, realizamos una discusión.


2001 ◽  
Vol 19 (10/12) ◽  
pp. 1241-1258 ◽  
Author(s):  
P. M. E. Décréau ◽  
P. Fergeau ◽  
V. Krasnoselskikh ◽  
E. Le Guirriec ◽  
M. Lévêque ◽  
...  

Abstract. The Whisper instrument yields two data sets: (i) the electron density determined via the relaxation sounder, and (ii) the spectrum of natural plasma emissions in the frequency band 2–80 kHz. Both data sets allow for the three-dimensional exploration of the magnetosphere by the Cluster mission. The total electron density can be derived unambiguously by the sounder in most magnetospheric regions, provided it is in the range of 0.25 to 80 cm-3 . The natural emissions already observed by earlier spacecraft are fairly well measured by the Whisper instrument, thanks to the digital technology which largely overcomes the limited telemetry allocation. The natural emissions are usually related to the plasma frequency, as identified by the sounder, and the combination of an active sounding operation and a passive survey operation provides a time resolution for the total density determination of 2.2 s in normal telemetry mode and 0.3 s in burst mode telemetry, respectively. Recorded on board the four spacecraft, the Whisper density data set forms a reference for other techniques measuring the electron population. We give examples of Whisper density data used to derive the vector gradient, and estimate the drift velocity of density structures. Wave observations are also of crucial interest for studying small-scale structures, as demonstrated in an example in the fore-shock region. Early results from the Whisper instrument are very encouraging, and demonstrate that the four-point Cluster measurements indeed bring a unique and completely novel view of the regions explored.Key words. Space plasma physics (instruments and techniques; discontinuities, general or miscellaneous)


Sign in / Sign up

Export Citation Format

Share Document