Table of Contents
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1. 2012 WORKSHOP REPORT: Tail-Inner Magnetosphere Interactions (TIMI)
   Focus Group
2. JOB OPENING: Research Scientist Position at UNH
======================================================================

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                     **   THE GEM MESSENGER   **
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                                                  Volume 22, Number 19
                                                       August 23, 2012
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1. 2012 WORKSHOP REPORT: Tail-Inner Magnetosphere Interactions (TIMI)
   Focus Group
----------------------------------------------------------------------
From: Pontus Brandt, John Lyon and Frank Toffoletto
      <toffo at rice.edu>, Conveners

The focus group profited from two excellent tutorials related to focus 
group concerns: the first presented by Harry Warren who discussed 
supra-arcade down flows and comparative solar/geospace systems, and 
the second by Dick Wolf on the physics of bubbles and BBFs.

*The first breakout session on Wednesday consisted of invited 
presentations reviewing the state of our understanding of interactions 
between the tail and the inner magnetosphere interactions.*

Vassilis Angelopolous (UCLA) gave an overview of the status of 
observations and theory/simulations relating to depolarization fronts 
(DF). He noted the importance of force balance and the associated 
Birkeland currents both as observed and simulated -- ahead of the 
front the currents are characterized as having a region-2 sense while 
within the bubble itself the currents have a region-1 sense.  

John Lyon (Dartmouth College) gave a review on the properties of BBFs 
and bubbles seen in recent high-resolution LFM simulations. At the 
current resolution of the code, the LFM is able to resolve BBFs in the 
tail and is close to resolving their impact in the ionosphere.  

Jian Yang (Rice) described causes and effects of DF as seen in the 
RCM-E; his results suggest that the westward electrojet peaks at the 
equatorial edge of bubbles and that bubble injection can increase ring 
current pressure by 10 nPa in RCM-E simulations. 

Jimmy Raeder (UNH) discussed several related topics. He has found that 
the breakdown in force balance before reconnection is associated with 
a KY0 ballooning mode although the exact nature of this instability is 
not clear. He noted the appearance of other ballooning structures in 
the tail about 1 Re in scale size. These structures look like beads in 
the aurora, consistent with some observations. He presented slides 
from a recent talk by Tetsuo Matoba et al. who observed auroral beads 
from the ground and concluded that they are not local ionospheric 
effects since they are conjugate between hemispheres. These beads 
drift with speeds of about 5 km/s; such motion is difficult to explain 
with ballooning.  He also reported on simulation work by Ping Zhu on 
bubble formation mechanisms, starting from a Harris sheet and 
developing an axial-tail instability. Zhu [2011] also found entropy 
minima/maxima (bubble/blob) pairs forming, consistent with the recent 
work of Hu et al., [2011]. 

Vahe Peroomian (UCLA) gave a brief presentation of large-scale kinetic 
simulations of the 8-9 March 2008 storm, launching H+ in the solar 
wind and O+ from the ionosphere. He found that the geoeffective entry 
region was 40-90 Re down tail. 

*The first session on Thursday focused on observation-based 
presentations.*

Andrei Runov (UCLA) looked at transient dipolarizations. Taking 
advantage of a unique configuration in April 2009 when all five THEMIS 
spacecraft had favorable radial conjunction he found a strong DF Bz 
signature in all of the spacecraft except the inner one at 8 Re. GOES 
and THEMIS-B saw oscillations in both particle velocity and magnetic 
field which he concluded were diamagnetic oscillations from mirror-
mode-like waves. 

Larry Lyons (UCLA) discussed mesoscale flows aligned with streamers. 
Flow channels from as high as 85 MLAT are seen together with PBI 
(Poleward Boundary Intensifications). 

Toshi Nishimura (UCLA) discussed PBI streamers associated with 
substorm onset. His results suggest that reconnection causes the 
streamers, and the associated flow bursts lead to intensification of 
the diffuse aurora and onset. 

Bea Gallardo (UCLA) looked at mesoscale flow channels associated with 
auroral streamers, showing that flow channels and streamers appear 
almost simultaneously with flow enhancements east of the streamers. 
Poleward flows appear (~24% of the time). 

Ying Zou (UCLA) showed statistics of the relationship between 
mesoscale polar cap flows and PBIs/streamers. 82% show occurrence of 
equatorward flow before a poleward boundary intensification with a 
delay of around 0-3 minutes.

Shin Ohtani (APL) showed examples of DF bouncing/overshoots at 9 Re, 
as well as evidence of dipolarization inside geosynchronous orbit. He 
also showed statistical plots of delta H (N-S component of the 
magnetic field) versus delta V (radial component) and the electric-
field inside geosynchronous (Cluster perigee) where dipolarizations 
show a dawn-dusk Electric-field. 

Pontus Brandt (APL) showed global ENA intensifications and timing 
during storm-associated substorms.  Around substorm onset a rapid 
decrease of ENAs occurs outside geosynchronous orbit, followed by 
dipolarizations and particle enhancements at GEO. He also showed 
coherent fine-structure/indentations at the outer edges of the bright 
ENA emissions from sequences of independent ENA images, which are 
statistically significant. 

Jerry Goldstein (SWRI) talked about TWINS stereo ENA observations of 
the anisotropy of injected ions.  Results from two events show a clear 
dawn-dusk asymmetry, where the PADs at dusk are more pancake than at 
dawn. 

Natasha Buzulukova (GSFC) showed results comparing HENA images and 
CRCM runs of protons in the 60-119 keV range during a substorm 
injection. Clear enhancements of protons in the ring current were 
noted. 

Xiaoyan Xing (UCLA) looked at the bubble precursor effect in the near-
Earth plasma sheet where it was found that the currents were ring 
current in front of the DF and R1-like behind. 

Yongli Wang (Univ. Maryland) reported on a statistical survey of 
magnetotail properties from XGSE = -10 to -80 Re using THEMIS/ARTEMIS 
data.

Eric Donovan (Univ. Alberta) advocated increasing the density of 
ground based stations in a focused region with imaging riometers, 
magnetometers, spectrometers, and VLF receivers. 

Jichun Zhang (UNH) discussed ion spectral dynamics at the inner edge 
of the ring current. He focused on nose features that are multiple 
bands of plasma sheet particles that occur in the ring current. He 
found that RCM and RCM-E modeling can reproduce some spectral features 
seen but multiple nose structures are difficult to reproduce.

*The second session on Thursday consisted of modeling-based 
presentations.*

Aleksandr Ukhorskiy (APL) looked at mechanisms of proton energization 
on dipolarization fronts. Using a simulation, he found that protons in 
the magnetotail can be accelerated up to ~100 keV in the DF, but that 
the level of energization depends on how long the particle can stay in 
phase with the front. 

Bill Lotko (Dartmouth) discussed influence of ionospheric conductance 
on cross-tail asymmetry in nightside reconnection and plasmasheet fast 
flows seen in LFM simulations.

Bin Zhang (Dartmouth) discussed the magnetotail origins of auroral 
Alfvenic power.

Jeremy Ouellette (Dartmouth) discussed sawtooth oscillations driven by 
ionospheric outflows as seen in the LFM global MHD code.

Joachim Birn (SSI) described his MHD results on bubbles, blobs and 
particle acceleration. The earthward transport of bubbles result in 
region-1 Birkeland currents and the depth of penetration into the 
inner magnetosphere depends on their reduction in the entropy. Bubbles 
that make it to the inner magnetosphere produce a substorm-current-
wedge-like signature. Regions of enhanced entropy (blobs) generate 
region-2 sense currents.

Misha Sitnov (APL) discussed the roles played by magnetic reconnection 
and buoyancy in the formation of mesoscale structures such as plasma 
bubbles. 

Natalia Buzulokova (GSFC) discussed the cause and effect relation 
between DF and reconnection using 2.5 D PIC simulations.  

Roxanne Katus (University of Michigan) discussed a statistical study 
of several storms between 1970-2011, binning Dst, IMF Bz, and AL.  She 
found that intense events show two-step/inflection main phase AL and 
Dst development implying that substorms play a strong role in intense 
events.

Antonius Otto (Univ. Alaska) noted that entropy is conserved when flux 
is circulated from the nightside to the dayside as demonstrated by MHD 
simulations. In these simulations, the MHD boundary condition is 
outflow on the nightside. The growth phase simulations see a major 
reduction of closed magnetic flux in the near-Earth tail and increased 
thinning of the near Earth tail current along with a strong reduction 
of the gradient of the flux tube entropy and a sharp transition to the 
inner edge. 

*The final session on Thursday consisted of spillover from the 
previous sessions and discussion of plans for upcoming meetings.*

David A. Mackler (SWRI) described his work with observations of the 
energetic neutral storm (ENA) geomagnetic emission cone (GEC).

Yasong Ge (UNH) talked about ion dynamics from an analysis of the Feb. 
27, 2007 DF event using observations from THEMIS and all sky imagers.  
Proton precipitation was enhanced following a DF, which suggests that 
the magnetotail DFs can accelerate and re-distribute plasma sheet ions 
into an earthward or field-aligned distribution.

Natalia Ganushkina (Univ. Michigan) showed inner magnetosphere model 
results – with different energies and temperatures - depend on where 
and how one applies the boundary conditions.

*In addition, the final session also consisted of a discussion of 
several open questions/suggestions on what to tackle during the course 
of the focus group.*

Roughly speaking, the discussion could be categorized as inner 
magnetosphere issues versus tail questions. In fact it was suggested 
that these categories were a way to organize our understanding. On the 
tail side, questions revolved around the formation of bubbles, the 
causes of their fast Earthward flow, and what causes the flows to be 
concentrated in limited regions of the nightside open closed boundary. 
Other important issues were the role of DF's in accelerating particles 
in the tail and the effect of the ionosphere on bubble formation and 
propagation.

The inner magnetosphere discussion centered on two broad areas: the 
transition from tail to inner magnetosphere and the capabilities of 
ring current models to reproduce the RC with and without the effects 
of bubbles. On the first issue, the role of bubbles in substorm 
expansion at L <10 was considered since most bubbles do not penetrate 
inside of 9 Re. Are there violations of adiabatic convection 
associated with the bubbles? On the second issue there was a general 
discussion of the current state of ring current models. No firm 
conclusion was reached about whether bubbles were required to form the 
ring current and whether variations of PV^5/3 along the outer boundary 
were necessary and could be accommodated in the various models.

New observations and analyses were discussed. RBSP figured prominently 
to look at DF interactions with inner magnetosphere: RBSP-ASI-SD to 
determine relation between streamers, PBIs, and ring current pressure. 
Ion spectral features will also be available over a wide range of L. 
The full range of THEMIS capabilities (ground and satellite) were 
discussed for statistical analysis of Auroral streamers, flows, and 
PBI's. Global ENA imaging from IMAGE and TWINS should be used to 
determine the the global nature and context of the fine-scale 
structure/indentations. Low altitude emission can also be used to 
resolve acceleration mechanisms.

We discussed what new model runs/improvements are needed. Major 
questions: How are bubbles created by reconnection or violation of 
frozen-in-flux? How can the transition to instability be properly 
handled and what impact does the presence of a ring current have on 
this? What is the best way to self-consistently model the transition 
region?

Future plans include a joint session with the "First 10 Minutes FG" in 
2013. We will invite key "anchor" speakers, schedule plenty of 
discussion time, and require walk-ons to be strictly relevant to the 
specific topic.

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2. JOB OPENING: Research Scientist Position at UNH
----------------------------------------------------------------------
From: Kai Germaschewski <kai.germaschewski at unh.edu>

The Space Science Center of the University of New Hampshire invites 
applications for a Research-Scientist II position to start in the fall 
of 2012. The successful applicant will carry out leading edge 
computational research on nonlinear plasma instabilities in laboratory 
and space plasmas under the supervision of Profs. K. Germaschewski and
J. Raeder. Applicants should have a Ph.D. in physics or a closely 
related discipline. Applicants should be familiar with numerical fluid 
and/or kinetic plasma simulations, and should have a strong background 
in magnetic confinement fusion plasma physics, magnetospheric physics, 
or both. Strong programming skills and familiarity with high-
performance computing are also required. The successful candidate is 
expected to work closely with other researchers and graduate students 
in the research group.

The position is available in the Space Science Center of the 
University of New Hampshire in Durham. The Space Science Center has 
active research groups in several areas, including experimental groups 
that participate in numerous space missions, theoretical, and 
simulation groups (see: http://www.eos.unh.edu). The successful 
candidate will have the opportunity to interact with a number of 
faculty, research staff, post-doctoral researchers, and graduate 
students. Substantial computational resources will be available for 
the simulation work.

Applicants should include a cover letter, CV, and statement of 
research interests, and be posted to the UNH online employment site
https://jobs.usnh.edu/applicants/jsp/shared/position/JobDetails_css.js
p?postingId=149133.
Candidates should arrange for three recommendation letters to be sent 
to Professor Kai Germaschewski at kai.germaschewski@unh.edu, 
preferably by e-mail. Applications received before September 30, 2012 
will receive full consideration.


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