SCOSTEP/PRESTONEWSLETTER
Vol. 23, April 2020

Inside this issue
Highlight on Young Scientists 1:

1

Ange Cynthia Umuhire/ Rwanda
Highlight on Young Scientists 2:

3

Gilda González/ Argentina
Highlight on Young Scientists 3:

This is a special issue containing 9 reports of SCOSTEP Visiting
Scholars (SVSs) as “Highlight on Young Scientists.”
Article 1:

Characterization of Coronal Mass Ejections
with High Frequency type II Solar Radio
Bursts4

Ritesh Patel/ India

Highlight on Young Scientists 4:

5Edith L. Macotela/ Finland

Ange Cynthia Umuhire
University of Rwanda, Kigali, Rwanda
Host Institute: NASA – GSFC, Greenbelt, MD, USA

Highlight on Young Scientists 5:

7Ange Cynthia
UmuhireMegha Pandya/ India
Highlight on Young Scientists 6:

8

Francisco Tapia-Vázquez/ Mexico

Highlight on Young Scientists 7:

9

Ram Singh/ India
Highlight on Young Scientists 8:

10

Victor U. J. Nwankwo/ Nigeria
Highlight on Young Scientists 9:

IntroductionTand three months. I am one of 2019
SCOSTEP visiting scholar at National
Aeronautics and Space AdministrationGoddard Space Flight Center (NASAGSFC).

he SCOSTEP Visiting Scholar (SVS)
program is a capacity building activity of SCOSTEP. The SVS program complements the current scientific program,
PRESTO, and SCOSTEP’s public outSummary of results obtained during
my visit at NASA-GSFC
reach activities. One of its objective is totrain graduate students in well-establishedhocks appearing ahead of Coronalsolar terrestrial physics laboratories andMass Ejections (CMEs) in the solar
institutions, for periods of between one

S

11

Reetika Joshi/ India

Upcoming Meetings

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Figure 1. The left side is the 13 January 2013 type II burst observed by Learmonthsolar radio spectrometer. As observed in figure 1(left), there is a fundamental
harmonic structure of type II burst, which followed a type III burst. The starting
frequency of the fundamental emission is 155 MHz. Figure 1 on the right shows the
CME shock associated with the January 13, 2013 burst, it was observed two minutes
after the appearance of type II.

SCOSTEP/PRESTO NewsletterVol. 23

Article
Highlight on Young Scientists

corona accelerate electrons that produce Langmuir
waves, which get converted into type II radio bursts by
the plasma emission mechanism. The radio signals arrive at Earth in ~8 min and hence can serve as advancewarning of incoming geoeffective CMEs. By using type
II solar radio burst (SRB) physical parameters, it is possible to derive important physical information of theassociated CMEs. Though recently there has been numerous analysis of CMEs from associated type II
bursts, much of work considered SRBs emitted at lower
frequencies and mainly detected by spaceborne spectrometers (i.e., WIND/WAVES).

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his research project specifically focused on spatiotemporal characterization and analysis of CMEs
using physical parameters of associated type II bursts
emitted at higher frequency (greater than 150 MHz) andobserved from various ground radio spectrographs. Figure 1 shows an example of high frequency type II burstwith the associated CME (on the right of Figure 1). The
January 13, 2013 type II burst started at 08:39:35 UT as
it can be estimated from its dynamic spectrum, its starting frequency is 155MHz and the drift rate of -0.70

MHz/s. The associated CME was located at N19W22
near the solar disk with an energetic flare (M1.7) as
observed on Figure 2. The CME shock was observed at
1.27Rs from the disk center. Figure 3 shows different
CME frames named following the CME evolution in
space and time. The estimated average CME speed was
as high as 645.55 Km/s.

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he study considered type II bursts which have clear
fundamental-harmonic structures that occurredfrom 2010 until 2016 when CMEs could be observed bySolar Dynamic Observatory (SDO) which was launchedin 2010. SDO observes CMEs very close to the Sun, so
we can understand the very early stage of shock formation. In general CMEs and solar radio bursts data are
available at the CDAW Data Center of NASA/GSFC. I
studied the relationship between CME kinematics andradio burst properties using parameters such as starting
frequency, CME radial distance and drift rate. The obtained results are significant and consistent with previous findings and soon will be communicated to a professional journal.

Meeting Report

Figure 2. The left side shows the flare location associated with the January 13, 2013 CME as observed by Solar
Dynamic Observatory on board Atmospheric Imaging Assembly (SDO/AIA). The right side illustrate the flare size
(M1.7) as observed by Geostationary Operational Environmental Satellite (GOES).

Upcoming Meetings
Announcement
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Figure 3. CME evolution in space and time is illustrated in terms of frames, the first frame shows the CME shockand the following frames (2 to 4) shows the CME evolution as observed by Solar Terrestrial Relation Observatory(STEREO). The average speed could be obtained by linearly fitting the height-time CME measurement (last plotof Figure 3). On the plot, the starting time of type II burst is shown. By fitting with the second order, thedeceleration of -0.17 km/s2 was observed and this may due to drag forces in interplanetary medium.

SCOSTEP/PRESTO NewsletterVol. 23

ue to time limitations, the proposed project will befinalized from my home country. We are proposing
to extend the work and analyze the interplanetary type II
bursts in order to characterize the associated Interplanetary CMEs (ICMEs). Also, the variation of the magnetic
field with respect to the CME heliocentric distances will
be analyzed for band-splitting type II bursts. I would
like to express my heartful thanks to the financial sup-port provided by SCOSTEP and NASA-GSFC. I
acknowledge Dr Nat Gopalswamy for helping me indata analysis and interpretation. I am grateful to all colleagues at NASA-GSFC, heliophysics science division
for their comments and discussions which improved thequality of this work. I thank the Cathoric University ofAmerica physics department staff especially heliophysics science division.

ArticleD

Highlight on Young Scientists

Article 2:

My Experience as a SVS Program Recipientat ISEE
Gilda González
National University of Tucumán, Tucumán, Argentina
Host Institute: Institute for Space-Earth Environmental Research (ISEE),
Nagoya University, Nagoya, Japan

Gilda González

I

Meeting Report

Figure 1. Picture of my presentation at the Division for
Ionospheric and Magnetospheric Research seminar

Upcoming Meetings

am a PhD student at National University of Tucuman—Argentina. My PhD focus on the analysis ofshort term variability of plasma bubbles (PBs) at low
latitudes under different solar and geomagnetic conditions. The PBs are regions of very low plasma density
and a high electric field. This electron density irregularities also cause scintillation of satellite signals and radarbackscatter at HF and VHF bands. Thanks to the SVS
program, I developed a research project at the Institutefor Space-Earth Environmental Research (ISEE), Nagoya University, Japan under the guidance of Dr. Shiokawa. I used all-sky imagers to monitor plasma disturbances in the ionospheric F region, the 630-nm airglow
intensity is proportional to the electron density ataround 250 km altitude. I compared these observations
with the S4 index that characterizes the scintillation
activity. In my PhD work I use data from GNSS receivers, ionosondes, magnetometers and instruments onboard spacecrafts, so this was the first time I used allsky imagers. Also, I have the opportunity to visit the
Shigaraki observatory and be part of the research groupmeetings where I could interact with researchers andstudents. My period at ISEE was very productive and I
consider that the training I received helped me improve
my research skills.

Announcement

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Article 3:

ArticleKinematics of Eruptive Prominences andTheir Relation to the Arrival Time of CMEs at Earth
Ritesh Patel
Indian Institute of Astrophysics, Bangalore, India

Highlight on Young Scientists

Host Institute: NASA – GSFC, Greenbelt, MD, USAC

oronal Mass Ejections (CMEs) are the main divers
for space weather. The initial evolution of CMEs
might have a significant impact on their propagation.
We have probed the lower corona and estimated thekinematic properties of eruptive prominences. The kinematics have been derived using an automated algorithm
based on Parabolic Hough Transform taking events

Ritesh Patelfrom a prominence eruption catalog made with images
taken by AIA 304 Å channel of SDO with 2 minutes
cadence. Currently the algorithm finds events from theonline catalog and tracks the eruptions by identifying
their corresponding ridges in height-time (r-t) plots asshown in Figure 1 and derive their kinematics.

Meeting Report

Figure 1. The ridge corresponding to prominence eruption is identified by the algorithm and overplotted in blue.

Upcoming Meetings(a)Announcement
4(b)Figure 2. Comparison of eruptions kinematics obtained by the automated algorithm and those by manual
tracking. (a) Average speed derived by the automated algorithm correlates with the manual values having
correlation coefficient of 0.64, (b) Average acceleration measured by the automated algorithm has weakcorrelation of 16% with the manual values.

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ur algorithm is able to identify these eruptions correctly and derive their properties including onset
time. Their kinematics properties are compared withvalues estimated by manual tracking. The average speed
derived by manual and automated process has a highcorrelation of 64%, whereas the average acceleration
had a lower value of 16% as shown in Figure 2.

SCOSTEP/PRESTO NewsletterVol. 23C

urrently, the algorithm shows better acceleration
values for slow eruptions than for relatively fasterones. Once the algorithm is optimized for both slow andfast eruptions, it can be implemented to all eruptions
listed in the SDO catalogue.

Article

Article 4:

New Contributions to the Study of VLF Radio
Wave Perturbations Measured at High Latitudes

Host Institute: Institute for Space-Earth Environmental Research (ISEE),
Nagoya University, Nagoya, Japan

T

Edith L.
Macotelaphenomena. The main results are:(i) The minimum energy a solar flare should have inorder to produce ionospheric disturbances, interpretedusing the minimum X-ray fluence, depends on the solar
cycle (Figure 1a). This energy is understood as the ionospheric sensitivity and for daytime conditions its value
lies in the range (1–12)×10-7 J/m2 [1].
(ii) The semiannual oscillation that appears in VLF
measurements was determined to be related to geomagnetic activity variations. At the same time, it was foundthat the 27-day solar rotation oscillation is dominantduring the declining phase of the solar cycle (Figure 1b)[2].

Meeting Report

he Earth-ionosphere system behaves as a waveguide for the propagation of very low frequency(VLF) radio waves. If in this system the electrical conductivity of its boundaries is disturbed, so is the propagation of VLF waves, which is observed as phase andamplitude variations of VLF waves with respect to theirquiescent levels. There is a diversity of physical phenomena able to significantly alter the conductivity of
the upper boundary. These phenomena can have their
origin at the Earth (e.g., lightning), in the solar system(e.g., solar flares) or even much farther away (e.g., galactic gamma-ray bursts). The aim of this study is toanalyze short- and long-term VLF variations measured
in Northern Finland and their associations to different

Highlight on Young Scientists

Edith L. Macotela
Sodankylä Geophsyical Observatory, University of Oulu, Finland

Upcoming Meetings

SCOSTEP/PRESTO NewsletterVol. 23

Announcement

Figure 1. (a) Average values of the minimum fluence, with their respective error bars, for every year of analysis
since December 2007 till January 2016. Minimum fluence values obtained by the coronal set of abundances are
represented by green filled circles and those obtained by the photospheric set of abundances are illustrated byorange stars. The photospheric values were multiplied by a factor of 0.75. The error bars are 1.3 standard
deviations of the minimum fluence values for every period of analysis. The magenta line is the 16-months smoothed
time variation of the Ly-α flux used as a proxy of Solar Cycle 24. (b) Cross-wavelet distribution for the daytime
VLF propagation data and solar Ly-α flux (upper panel) and AE index (lower panel). The black curve is the coneof influence and the black contours indicate 95% confidence level. The contours colors indicate the high (red) andno (white) significant common powers-of-two wavelet transform.

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Highlight on Young Scientists
Meeting Report
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6

Figure 2. (a) 10-day averages of the amplitude phase perturbation variability (black curve) contrasted with theatmospheric ozone number density (green curve) at 38–42 km. R is the correlation coefficient. (b) Example ofbanded emission (within the red ellipse) observed at Kannuslehto. One-hour frequency-time spectrogram of righthanded (reddish colors) and left-handed (greenish colors) polarization ratio. Measurements on 05 December 2013
since 16:42 UT.

(iii) The main characteristics of the observed VLF sunrise phase perturbation are derived from the shadowingof short wavelength solar UV radiation due to stratospheric ozone absorption when the Sun rises (Figure 2a)[3].

[2] E. L. Macotela, M. Clilverd, J. Manninen, T. Moffat-Griffin, D. Newnham, T. Raita, & C. Rodger (2019). D-region high latitude forcing factors. Journal of Geophysical Research: Space Physics, 124, 765–781.
https://doi.org/10.1029/2018JA026049.

(iv) Broadband VLF emissions with banded structure
were observed in the frequency range 16–39 kHz(Figure 2b), which are frequencies not usually used forthe study of whistler mode VLF emissions coming fromthe magnetosphere [4]. Searching for an explanation,
two different hypotheses were put forward. First, theymight be due to plasma instabilities in the magnetosphere, as in the case of structured auroral hiss [5]. Second, they could be formed in the Earth‐ionosphere
waveguide, as in the case of long‐distance propagationof lightning generated VLF emissions [6,7].

[3] E. L. Macotela, M. Clilverd, J. Manninen, D.
Newnham, & T. Raita (2019). The effect of Ozone
shadowing on the D-region ionosphere during sunrise.
Journal of Geophysical Research: Space Physics, 124,
3 729–3 742. https://doi.org/10.1029/2018JA026415.

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he mentioned results can provide useful constraints
on the long-term and short-term variability in coupled ion-neutral atmospheric models, thereby adding toour understanding of the response of the chemistry, dynamics and electrodynamics of the Earth’s ionosphereto solar and atmospheric forcing.

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ith the motivation to look for VLF banded structures using other ground-based receiver data, I
applied for the SVS program to a research visit at theInstitute for Space-Earth Environmental Research(ISEE), Nagoya University, Japan. Results of the visit
are twofold: my research and data analysis skills were
improved, and VLF emissions with banded structure are
now being observed at other auroral and sub-auroral
regions.
References[1] E. L. Macotela, J.-P. Raulin, J. Manninen, E. Correia, T. Turunen, & A. Magalhães (2017). Lower ionosphere sensitivity to solar X-ray flares over a complete
solar cycle evaluated from VLF signal measurements.
Journal of Geophysical Research: Space Physics, 122,
12 370–12 377. https://doi.org/10.1002/2017JA024493.

SCOSTEP/PRESTO NewsletterVol. 23[4] E. L. Macotela, F. Nemec, J. Manninen, O. Santolik,
I. Kolmasova, & T. Turunen. (2019). VLF emissions
with banded structure in the 16–39 kHz frequency range
measured by a high latitude ground-based receiver. Geophysical Research Letters, 46. https://doi.org/10.1029/2019GL086127.

[5] E. A. Titova, A. Demekhov, D. Pasmanik, V. Trakhtengerts, J. Manninen, T. Turunen, & M. Rycroft(2007). Ground-based observations at L~ 6 of multiband structures in VLF hiss. Geophysical Research Letters, 34, L02112. https://doi.org/10.1029/2006GL028482.
[6] J. Záhlava, F. Němec, O. Santolík, I. Kolmašová, M.
Parrot, & C. J. Rodger (2015). Very low frequency radio events with a reduced intensity observed by the low‐
altitude DEMETER spacecraft. Journal of GeophysicalResearch, Space Physics, 120, 9781–9794. https://doi.org/10.1002/2015JA021607.
[7] J. Záhlava, F. Němec, O. Santolík, I. Kolmašová, M.
Parrot & D. Kouba (2018). Selective attenuation oflightning‐generated whistlers at extralow frequencies:
DEMETER spacecraft observations. Journal of Geophysical Research, Space Physics, 123, 8631–8640.
https://doi.org/10.1029/2018JA025879.

Article

Article 5:

Overview of My Research Under SVS Program 2019
Megha Pandya
Indian Institute of Geomagnetism (IIG), Navi Mumbai, India

Highlight on Young Scientists

Host Institute: NASA – GSFC, Greenbelt, MD, USA

Megha PandyaIt is my honor and privilege to give a word about myresearch and lifetime opportunity that I was given
under 2019 SCOSTEP visiting scholar (SVS) program.
During my Ph.D tenure, I was selected to get training
under the Deputy Mission Scientist of Van Allen Probes
Mission - Dr. Shrikanth Kanekal at NASA-GSFC, USA
and I sincerely thank him for taking interest in my research proposal and hosting me for this program. I specially thank my Ph.D research supervisor (Prof. B.
Veenadhari), SCOSTEP’s Past President (Dr. Nat Gopalswamy) and entire SCOSTEP’s committee forproviding this opportunity.

Figure 1. Multiple drift echo observations of electron
Pitch angle distribution at different energies during
2016 July 19-20, using Van Allen Probes-A
observations.

derstand the extent of energization and attribution of its
physical mechanism. Some results are obtained andsome more analysis is under process. The manuscript
will be ready in couple of months.

Upcoming Meetings

urrently, I am working as a Research Associate at
IIG on “Study of the radiation belt electron flux
response to the changing solar wind and interplanetaryconditions”. During this visit, I was trained to expand
my technical and scientific skills to achieve the proposed research plan along with active scientific discussions with the students and other eminent scientists. The
purpose of the internship was to investigate of IP shock
response to the radiation belt electrons using Van Allen
Probes data during declining phase of the solar cycle 24.
For this, Pitch angle resolved dataset are utilized forcharacterizing electron flux response as shown in Figure
below. Crucial observations of electron PADs werecompared at different energies during IP shock to un-

Meeting ReportC

Announcement

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Article 6:

ArticleStellar Atmospheres in Solar like Stars
at Millimeter and Sub-millimeter Wavelengths

Highlight on Young Scientists

F. Tapia-Vázquez1,3, V. De la Luz2, J.P. Raulin3 and L. A. Zapata1
1Instituto de Radioastronomía y Astrofísica,
Universidad Nacional Autónoma de México, Morelia, Mexico
2Escuela Nacional de Estudios Superiores Unidad Morelia,
Universidad Nacional Autónoma de México, Morelia, México
Host Institute:
3Centro de Rádio Astronomía e Astrofísica Mackenzie, Escola de Engenharia,
Universidade Presbiteriana Mackenzie, São Paulo, Brazil

Francisco
Tapia-Vázquez

Meeting Report
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Announcement
8

VictorDe la Luz

Jean-Pierre
RaulinLuis A. ZapataT

he atmosphere of the Solar-like stars is composedof the photosphere, chromosphere, transition zone,
and corona. The chromosphere is the layer where thetemperature goes from 4000 K to 8000 K and is studied
at ultraviolet, visible, infrared, millimeter and (sub)millimeter wavelengths (Wedemeyer et al. 2016).
The first chromospheric models were obtained thanks to
the ultraviolet observations (Vernazza et al. 1981;
Avrett & Loeser 2008). However, recent observations
made with the Solar Submillimeter Telescope (SST)and the Atacama Large Millimeter / Submillimeter Array (ALMA) have shown that the chromosphere has
lower temperatures than expected by ultraviolet models(Linsky 2017).

Figure 1. A photo of the professor Jean-Pierre Raulin
and me at Mackenzie University in São Paulo, Brazil.

W

Referencese have developed the KINICH-PAKAL (TapiaVázquez, & De la Luz 2020) code that use theLevenberg-Marquard algorithm as a nonlinear fit method, PAKAL-MPI as a chromospheric model of the solar
atmosphere, and observations at wavelengths ranging
from infrared to millimeter to generate a more accurate
model of the chromospheres of the solar-type stars.

K
D

INICH-PAKAL has allowed us to study in detail
how the physical conditions of the atmospherechange as a function of its effective temperature.
eveloping these models is necessary for debris disk
studies (White et al. 2018), study the conditions
under which flares are formed (MacGregor et al.2018)
and the possible physical mechanisms of flux variationsin the stars (Liseau 2019).

Avrett, E. H., & Loeser, R. 2008, ApJS, 175, 229.
Linsky, J. L. 2017, ARA&A, 55, 159.
Liseau, R. 2019, arXiv:1904.03043.

MacGregor, M. A., Weinberger, A. J., Wilner, D. J.,
Kowalski, A. F., & Cranmer, S. R. 2018, ApJ, 855, L2.
Tapia-Vázquez, F., & De la Luz, V. 2020, ApJS, 246, 5.
Vernazza, J. E., Avrett, E. H., & Loeser, R. 1981, ApJS,
45, 635.
Wedemeyer, S., Bastian, T., Brajša, R., et al. 2016,
SSRv, 200, 1.
White, J.A., Aufdenberg, J., Boley, A.C., 2018, ApJ,
859(2), p.102.

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Article

Article 7:

Simultaneous Observations of the Electron Density
in the Ionosphere and Magnetosphere
Ram Singh
Indian Institute of Geomagnetism (IIG), Navi Mumbai, India

Highlight on Young Scientists

Host Institute: Institute for Space-Earth Environmental Research (ISEE),
Nagoya University, Nagoya, Japan

Ram Singh

I

Figure 1. A group photo during SCOSTEP visiting
scholar (SVS) program visit at Institute for SpaceEarth Environmental Research (ISEE) Nagoya
University, Japan (November, 2019).

Meeting Reportam one of the luckiest among many that got the chance
to visit Institute for Space-Earth Environmental Research (ISEE) Nagoya University Japan, under the 2019
SCOSTEP visiting scholar (SVS) program. First, I want toexpress my sincere gratitude to the SCOSTEP committee
to organize such a wonderful scientific (SCOSTEP visiting
scholar (SVS)) program for young researchers. I sincerely
thank Prof K. Shiokawa for accepting my application forthis program. He is a great professor, instructor, and able
to clearly explain complex topics and nuances. I also spacially thank my Ph.D research supervisor Prof. S. Sripathi
who recommened me for this program. During this visit, I
got the opportunity to speak about my research work andgot opinions about it from many experts in ISEE. Since thearea is not exactly the same, but they helped me with adifferent insight, suggested few points in my research thatare interesting from their viewpoints.

Upcoming MeetingsCurrently, I am working at the Indian Institute of geomagnetism Mumbai, in India as Research Associate.
My Ph.D. research topic is "Coupling of the solar-driven
prolonged and transient processes to the equatorial and low
latitude ionosphere". During the SVS program, I workedon the simultaneous observations of electron density in theionosphere (~300 km) and magnetosphere (~4.5 RE) using
the GPS Total Electron Content (TEC) and Radiation Belt
Storm Probes (RBSP) satellite-A and-B data. To calculate

Announcement

Figure 1. (A) shows the snapshots of GPS TEC between ~02:00-04:30 UT (~0.5 hr intervals) over the North
American Sector on the 24th June 2015. The blue and red curves show magnetic footprints of RBSP-A and B (~300km). Theelectron density enhancement and longitudinal (westward) propagation depicts in figure A (a-c). The
keogram of absolute TEC (aTEC) along the 60olatitude shows westward and eastward propagation of the electron
density in the ionosphere (in the figure-B (a)). The bottom panel of the figure-B (b) shows, electron density
variations obtained from the RBSP-A (red) and RBSP-B (blue). The green and black color curvesshow electron
density variationat the magnetic footprints of RBSP-A and B in the ionosphere at ~300 km.
the magnetic footprints of the satellites, we used Tsyganenko model (TSO4). The work mainly focused on thefollowing points. (1) The observations of Storm Enhanced
Density (SED) event. (2) Longitudinal propagation of solar
terminator structure observed by RBSP-A and B satellites,and electron density enhancement before the sunset terminator, and (3) Whether, at the same time, Gravity waves ortraveling ionospheric disturbances (TIDs) effects can beseen in the ionosphere and magnetosphere.

SCOSTEP/PRESTO NewsletterVol. 239

Article 8:

ArticleStudy of geomagnetic storm-induced ionospheric changes
in D-region using very low frequency (VLF) radio signal
Victor U. J. Nwankwo
Anchor University, Lagos, Nigeria

Highlight on Young Scientists

Host Institute: Centro de Radio Astronomia e Astrofísica Mackenzie (CRAAM),
São Paulo, Brazil

M

Meeting Reporty SVS work at CRAAM relates to the investigation of geomagnetic storm-induced ionospherechanges in the D-region over four signal propagation
paths (PPs) of very low frequency (VLF) radio waves
covering parts of Europe and Brazil. Our preliminary
results showed significant reduction in the amplitude of
VLF signal following geomagnetic storm. Fig. 1 shows
one of the four storm cases analyzed. We observed asignificant reduction in the daytime signal amplitude(DTMA) in all the propagation paths (PP1, PP2, PP3
and PP4) by 3.04 dB, 0.21 dB, 2.01 dB and 2.10 dB,
respectively following a storm. The mean signal amplitude before sunrise (MBSR) also showed reduction in 2of the 4 PPs, while the mean signal amplitude after sunset (MASS) showed reduction in 3 of 4 PPs. The outcome was quite similar in all the four storm cases analyzed. These results were consistent with some earlier
reports (e.g., [1, 2]). We also observed the occurrence of
anomalous signal in NAA signal received at ROI stationin Brazil following geomagnetic storm. In fig 2 weshow the anomalous signal observed in NAA-ROI PP
during geomagnetic storms on 17 September, and 25
October 2011. This is the first time such anomaly was
noticed in the received data analyzed at CRAAM.

T
Upcoming Meetings
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10

Victor U. J.
Nwankwohe SVS program provided me a stimulating environment and opportunity to work with Prof. J.-P.
Raulin and Prof. Emilia Correia. It also offered me theopportunity to meet and interact with other young scientists, scholars and faculty members at CRAAM (andother institutions in São Paulo), and exchanged views

Figure 2. VLF signal anomaly observed in NAA-ROI
propagation path during geomagnetic storms of 17
Sept. and 25 Oct. 2011.

on a variety of related scientific themes. The SVS program broadened my expertise and experience (despite
the short duration) and enhanced my capabilities to contribute to teaching and research. It also provided a platform to open discussions on possible scientific cooperation and collaboration between my host institution andmy home university, which eventually culminated tosigning of MoU between Universidade Presbiteriana
Mackenzie, São Paulo (Brazil) and Anchor University,
Lagos (Nigeria), for future collaborations.
References

Figure 1. Variations in Dst, AE, By and Bz, and VLF
amplitude (hourly mean) for DHO-A118, GQD-A118,
NAA-A118 and NAA-ROI propagation paths during 16-19 Sept. 2011. The blue bar is the signal amplitude andthe red bar is the hourly mean deviation (σ) in amplitude.

SCOSTEP/PRESTO NewsletterVol. 23

1.

Peter et al., 2006. Perturbations of mid-latitude sub-ionospheric VLF signals associated with lower
ionospheric disturbances during major geomagnetic storms. J. Geophys. Res. 111, AO3301.

2.

Nwankwo at al., 2016. Probing geomagnetic storm-driven magnetosphere-ionosphere dynamics in Dregion via propagation characteristics of very low
frequency radio signals, J. Atmos. Solar-Terr.
Phys. 145, 154-169.

Article

Article 9:Multi-viewpoint and Multi-wavelength Study ofa Jet Like CME
Reetika Joshi
Department of Physics, DSB Campus, Kumaun University, Nainital, India

S

Reetika Joshi

edge of the jet in SDO/AIA and STEREO-B/EUVI 304
channel at 21:56 UT is shown in Figure 1. The CME
looked like a giant jet with an angular width of 25 degrees in the solar corona as viewed from STEREO-B
and SOHO.

T

hen we applied the ice-cream cone model, which isa simplified form of the Graduated Cylindrical
Shell (GCS, Thernisien et al. (2006)) model, to examine the direction and velocity of the CME as shown in
Figure 2. Its propagation speed was found to be 450 km/s.

Meeting Report

Figure 1. The leading edge of the jet in SDO/AIA 304 Å(a) and in STEREO B EUV 304 Å (b) at 21:56 UT
presented as the yellow circle.

Upcoming Meetingsolar active phenomena can be divided into two categories namely: Large scale activities (solar filaments, solar flares, coronal mass ejections (CMEs)) andsmall scale activities (solar jets/surges, ellerman bombs,
microflares, spicules) (Wang et al., 2016, Liu et al.,2019). The large scale activities affect our space weather directly. However, there are cases where the small
scale events can also be associated with CMEs and affect our space weather. One of the important small scalesolar activities is solar jet. Solar jets are defined as thecollimated plasma ejections emitted in different temperatures in the low solar atmosphere and reaching highaltitudes into the corona. They are observed in the wide
range of electromagnetic spectra such as: H-alpha (Roy1973; Schmieder et al. 1988; Uddin et al. 2012), Ca II H
(Shibata et al. 2007), Extreme Ultraviolet (EUV)(Alexander & Fletcher 1999; Guo et al. 2013, Joshi etal. 2017) and soft X-ray (Shibata et al. 1992; Sterling etal. 2015). From the the morphological description, solar
jets are divided into two categories: ‘standard’ and‘blowout’ jets (Moore et al. 2010). Standard jets have anarrow spire with a relative dim base, whereas theblowout jets reveal an initial phase quite similar tostandard jets, but with a bright base. Blowout jets areafterwards followed by a violent flux rope eruption andthen consequent broadening of the spire (Sterling et al.
2010; Liu et al. 2011). Later on this violent flux rope
eruption can be observed as CMEs (Liu et al. 2015, Raouafi et al. 2016; Zuccarello et al., 2017, Chandra et al.,2017). The observations show that jets can be topologically complex and may contribute to the heating of thesolar corona and the acceleration of the solar wind(Zhelyazkov et al. 2019).

Highlight on Young Scientists

Host Institute: University of Science and Technology of China,
School of Earth and Space Sciences Anhui, Hefei, China

R

Announcement

ecently, we studied a CME associated solar jet
event on April 28, 2013. To study the event fromthe multiview point we used the EUV and coronal white-light data from Solar Dynamics Observatory (SDO,
Pesnell et al. (2012)), Solar TErrestial RElations Observatory (STEREO, Howard et al. (2008)), and SOlar andHeliospheric Observatory (SOHO, Brueckner et al.
(1995)). Our study on the kinematics and spatial evolution of the jet guided us that the jet was clearly associated with the narrow CME.

The jet erupted from the active region NOAA 11731
in the association with a C1.5 class flare towards
the northern direction. After reaching some height, thejet deflected from the initial direction and revolved
around the north-east direction. For the real propagation
direction we analysed SDO/AIA and STEREO/EUVI
data and found that the jet escaped from the surface
with a real propagation speed of 200 km/s. The leading

Figure 2. The The GCS modelling of the narrow CME
in STEREO-B COR2 (first column), and SOHO/LASCO C2 (last column).

SCOSTEP/PRESTO NewsletterVol. 2311

Article
Highlight on Young Scientists

Figure 3. The global (a) and local (b) extrapolation at the jet base. Panel (a): PFSS extrapolation at the active
region Closed and open magnetic field lines are shown with the white and pink lines. The open (pink) field lines
are exactly in the same way as of the jet propagation direction. Panel (b): The open (cyan) magnetic lines areshowing the path of the jet in the northward direction overlaid on the AIA 304 Å.

W

Meeting Report

e further applied the Potential Field Source Surface (PFSS) model to investigate the global magnetic topology near the jet source region (see Figure 3a)
and applied the Fourier transformation method(Alissandrakis 1981) for the coronal extrapolation fromthe line of sight magnetogram to reveal the details in thejet base (see Figure 3b). It was found that the open fieldlines (Figure 3 (a)) coincide well with the moving direction of the jet and the jet base just next to the open fieldlines is covered with the closed loops.

T

his study of a narrow CME caused by the jet gives
a worth evidence that some small scale ejections(jets) from the solar disk are able to escape and reachthe solar corona as a CME, suggesting the tight connection between the small scale activities and large scale
eruptions. In this direction, we are looking forward tofind the clear in situ measurements from the newly
launched Parker Solar Probe.

Upcoming MeetingsWe thank SDO, STEREO, and SOHO scienceteams for the free access to the data. RJ thanks to
SCOSTEP Visiting Scholarship program and Prof.
Yuming Wang and his group for providing the opportunity to carry this work at University of Science andTechnology of China.
References

Alexander, D., Fletcher, L., 1999, Solar Phys., 190, 167.
Alissandrakis, C. E. 1981, A&A, 100, 197.
Brueckner, G. E., et al. 1995, Sol. Phys., 162, 357.

Announcement
12

Chandra, R., Mandrini, C, H. , Schmieder, B., et al., A& A, 2017, 598, A41.
Guo, Y., Demoulin, P., Schmieder, B., et al. 2013.,
A&A, 555, 19.

SCOSTEP/PRESTO NewsletterVol. 23

Howard, R. A., et al. 2008, Space Sci. Rev., 136, 67.
Joshi, Reetika, Schmieder, B., Chandra, R., Solar Phys.,292, 152.
Liu, J., Wang, Y., Shen, C., et al., 2015, ApJ, 813, 115.
Liu, J., Wang, Y., Erdelyi, R., 2019, Frontiers in Astronomy and Space Sciences, 6, 44.
Pesnell, W. D., Thompson, B. J., & Chamberlin, P. C.
2012, Sol. Phys., 275, 3.
Raouafi, N. E., Patsourakos, S., Pariat, E., et al. 2016,
Space Scien. Rev. 2016.
Roy, J.R., 1973, Solar Phys., 28, 95.
Schmieder,B., Mein,P., Simmett, G.M., Tandberghanssen, E., 1988, A&A, 201, 327.

Shibata, K., Ishido, Y., Acton, L. W., et al. 1992, PASJ,
44, L173.
Shibata, K., Nakamura, T., Matsumoto, T., et al., 2007,
Science, 318, 1591.
Sterling, A. C., Moore, R. L., Falconer, D. A., 2015,
Nature, 523, 437.
Uddin, W., Schmieder, B., Chandra, R., et al. 2012,
ApJ, 752, 70.

Wang,Y., Zhang, Quanhao; Liu, Jiajia, 2016, JGRA,
121,7423.
Zuccarello, F.P., Chandra, R., Schmieder, B., AulanierG., Joshi Reetika, 2017, A&A, 601, A26.
Zhelyazkov, T., Chandra, R., Joshi, R., 2019, Frontiersin Astronomy and Space Sciences, 6, 33.

Upcoming meetings related to SCOSTEPContact Information

EGU General Assembly 2020

May 4-8, 2020

Onlinehttps://www.egu2020.eu/

European Meteorological Society (EMS) session on "The interconnection between the
Sep. 7-11, 2020
Sun, space weather, and the upper and middle atmosphere"

Bratislava, Slovakia

https://www.ems2020.eu/
home.html

International Colloquium on Equatorial and
Low-Latitute Ionosphere

Sep. 14-19, 2020

Ota, Nigeria

https://carnasrda.com/icelli

AGU Fall Meeting 2020

Dec. 7-11, 2020

San Francisco, CA,USA

https://www.agu.org/fallmeeting

COSPAR 2021

Jan. 28-Feb.4,
2021

Sydney, Australia

https://www.cospar2020.org/

EGU General Assembly 2021

Apr. 25-30, 2021

Vienna, Austria

https://www.egu.eu/

8th International HEPPA-SOLARIS 2020
Meeting

Jun. 8-10, 2021

Bergen, Norway

https://
heppasolaris2020.w.uib.no/

IAMAS

Jul. 18-23, 2021

Busan, Korea

http://baco-21.org/2021/english/
main/index_en.asp

AOGS 2021

Aug. 1-6, 2021

Singapore

http://www.asiaoceania.org/
society/index.asp

IAU 2021 General AssemblyAug. 16-27, 2021

Busan, Korea

http://www.iauga2021.org/

IAGA 2021

Aug. 22-27, 2021

Hyderabad, India

http://www.iaga-iaspeiindia2021.in/

URSI General Assembly and Scientific Symposium (GASS2021)

In late August andearly September, Rome, Italy
2021

AGU Fall Meeting 2021

Dec. 13-17, 2021

New Orleans, LA,USASCOSTEP’s 15th Quadrennial SolarTerrestrial Physics Symposium (STP-15)

Feb. 21-25, 2022

Alibag, India

EGU General Assembly 2022

Apr. 3-8, 2022

Vienna, Austria

https://www.egu.eu/

COSPAR 2022

Jul. 16-24, 2022

Athens, Greece

http://
www.cosparathens2022.org/

AOGS 2022

Aug. 14-19, 2022

Melbourne, Australia

http://www.asiaoceania.org/
society/index.asp

AGU Fall Meeting 2022

Dec. 12-16, 2022

Chicago, IL, USA

https://www.agu.org/fallmeeting

IUGG 2023

In July, 2023

Berlin, Germany

http://www.iugg.org/

AGU Fall Meeting 2023

Dec. 11-15, 2023

San Francisco, CA,USA

https://www.agu.org/fallmeeting

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ArticleConference

Upcoming Meetings

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SCOSTEP/PRESTO Newsletter

13

The purpose of the The purpose of the SCOSTEP/PRESTO newsletter is to promote communication among scientists related to solar-terrestrial
physics and the SCOSTEP’s PRESTO program.
The editors would like to ask you to submit the following articles to the SCOSTEP/PRESTO newsletter.
Our newsletter has five categories of the articles:
1. Articles— Each article has a maximum of 500 words length and four figures/photos (at least two figures/photos).
With the writer’s approval, the small face photo will be also added.
On campaign, ground observations, satellite observations, modeling, etc.

2. Meeting reports—Each meeting report has a maximum of 150 words length and one photo from the meeting.
With the writer’s approval, the small face photo will be also added.
On workshop/conference/ symposium report related to SCOSTEP/PRESTO
3. Highlights on young scientists— Each highlight has a maximum of 200 words length and two figures.
With the writer’s approval, the small face photo will be also added.
On the young scientist’s own work related to SCOSTEP/PRESTO
4. Announcement— Each announcement has a maximum of 200 words length.
Announcements of campaign, workshop, etc.
5. Meeting schedule
Category 3 (Highlights on young scientists) helps both young scientists and SCOSTEP/PRESTO members to know each other. Please contact
the editors if you know any recommended young scientists who are willing to write an article on this category.
TO SUBMIT AN ARTICLE
Articles/figures/photos can be emailed to the Newsletter Secretary, Ms. Mai Asakura (asakura_at_isee.nagoya-u.ac.jp). If you have any questions or problem, please do not hesitate to ask us.
SUBSCRIPTION - SCOSTEP MAILING LISTThe PDF version of the SCOSTEP/PRESTO Newsletter is distributed through the SCOSTEP-all mailing list. If you want to be included in themailing list to receive future information of SCOSTEP/PRESTO, please send e-mail to “patricia.doherty_at_bc.edu” or “sean.oconnell.2 atbc.edu” (replace “_at_” by “@”) with your name, affiliation, and topic of interest to be included.

Editors:

Kazuo Shiokawa (shiokawa_at_nagoya-u.jp)
SCOSTEP President,
Center for International Collaborative Research (CICR),
Institute for Space-Earth Environmental Research (ISEE), Nagoya University,
Nagoya, Japan
Patricia H. Doherty (patricia.doherty_at_bc.edu)
SCOSTEP Scientific Secretary,
Boston College, Boston, MA, USA

Ramon Lopez (relopez_at_uta.edu)
PRESTO chair,
University of Texas at Arlington, TX, USA

Newsletter Secretary:

Mai Asakura (asakura_at_isee.nagoya-u.ac.jp)
Center for International Collaborative Research (CICR),
Institute for Space-Earth Environmental Research (ISEE), Nagoya University,
Nagoya, Japan

PRESTO co-chairs
and Pillar co-leaders:

Katja Matthes (co-chair), Jie Zhang (co-chair), Allison Jaynes (Pillar 1 co-leader), Emilia Kilpua(Pillar 1 co-leader), Spiros Patsourakos (Pillar 1 co-leader), Loren Chang (Pillar 2 co-leader),Duggirala Pallamraju (Pillar 2 co-leader), Nick Pedatella (Pillar 2 co-leader), Odele Coddington(Pillar 3 co-leader), Jie Jiang (Pillar 3 co-leader), and Eugene Rozanov (Pillar 3 co-leader)

SCOSTEP Bureau:

Kazuo Shiokawa (President), Daniel Marsh (Vice President), Nat Goplaswamy (Past President),
Patricia Doherty (Scientific Secretary), Aude Chambodut (WDS), Jorge Chau (URSI), KyungSuk Cho (IAU), Yoshizumi Miyoshi (COSPAR), Renata Lukianova (IAGA/IUGG), Peter
Pilewskie (IAMAS), Annika Seppälä (SCAR), and Prasad Subramanian (IUPAP)
web site: www.bc.edu/scostep.

14

SCOSTEP/PRESTO NewsletterVol. 23