FG: Tail-Inner Magnetosphere Interactions

Tail-inner magnetosphere interactions (TIMI)

Executive Summary

The overarching science goal of this NSF/GEM Focus Group is to Understand modes of transport and acceleration that are responsible for the efficient plasma heating within the magnetotail and the inner magnetosphere. Understanding the physical mechanisms behind the transport and acceleration of plasma in to the inner magnetosphere is one of the missing links in our ability to predict near-Earth space weather. Recent observations and theoretical work have cast doubt on the idea that a global, laminar process can be responsible for the formation of the ring current from tail plasma. Thus, a picture is evolving in which meso-scale processes are the conduits for the energization of the inner magnetosphere. Flow channels, bursty bulk flows (BBFs), “bubbles” and associated dipolarization fronts (DFs) have emerged as potentially a key player in setting up the enhanced pressure in the inner magnetosphere that directly impacts its entire structure and dynamics. However, other meso scale processes, such as alternate types of tail turbulence, may also contribute. Recent observations and modeling have raised the controversial question whether a single phenomenon is responsible for inner magnetosphere energization, irrespective of activity level. This 4-year focus group will bring together data and modeling efforts to determine whether meso-scale processes are responsible for ring current energization, what those processes are, and how they can be fit into a comprehensive GGCM. It represents a new and timely topic propelled by the emerging model capabilities to couple MHD and kinetic physics as required. The growing and future data sets of THEMIS and RBSP will be critical to investigate the role and impact of these phenomena during strong convection, large substorms, quiet times. Whereas past FGs have dealt with the self-consistent treatment of the inner magnetosphere and the transport within the tail, this proposed FG focuses on a gap, not directly addressed by past FGs, that deals with the challenging interface region between the tail and the inner magnetosphere by specifically studying the formation, evolution and physics of the fast flows/BBFs/bubbles and their impact on the inner magnetosphere.

The TIMI Focus Group includes the following science questions and topics:

1. What meso-scale phenomena are responsible for plasma transport and heating from the tail to the inner magnetosphere?
2. What is the physics of Flow channels/BBF’s/Bubbles?
3. What is the role of ionospheric conductivity (including meso-scale structure resulting from precipitation enhancements) and flows in the formation and evolution of bubbles and other meso-scale structure s?
4. Theory and Modeling of Flow channels/BBF’s/Bubbles.
5. How does the transport and acceleration at Saturn, Jupiter and in the solar corona compare to that of the terrestrial magnetosphere?
6. Examine and apply the concept of entropy as an organizing principle to understand physical processes in the magnetosphere.

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2015 GEM Workshop : Tail Inner-magnetosphere interactions

The GEM focus group on Tail-Inner Magnetosphere Interactions (TIMI) will hold its breakout sessions on June 16-19, 2015. There will be 4 TIMI-related focus group breakouts:

1. Tuesday, June 16, 1:30-3:00 – Joint session Tail-Inner Magnetosphere Interactions and Magnetic Reconnection in the Magnetosphere. [From the “Magnetic Reconnection in the Magnetosphere” announcement]. This session will focus on reconnection in the magnetotail and its effects on the inner magnetosphere. In particular, a topic that has generated a lot of interest of late are the kinetic processes associated with energy conversion and the formation and consequences of dipolarization fronts. We also encourage discussion on reconnection onset in the magnetotail - tearing vs. ballooning/interchange. Other relevant topics are welcome.

2. Thursday, June 18: 10:30 – 12:15 – Joint session Tail-Inner Magnetosphere Interactions and Storm-Time Inner Magnetosphere- Ionosphere Convection. Details TBA

3. Thursday, June 18: 1:30 – 3:00 PM – Tail-Inner Magnetosphere Interactions: General session, Topics: The impact of bubbles on the inner magnetosphere, ring current buildup, particle energization and injections, effects in the ionosphere, the production and impact of waves.

4. Thursday, June 18: 3:30 – 5:00 PM – Tail-Inner Magnetosphere Interactions: General session, overflow, as needed, and general discussion and plans for the upcoming and final year of this focus group.

We kindly ask presentations to be limited to 2-3 slides/5 minutes (no AGU style talks please). If you would like to be put on the schedule, please contact Frank Toffoletto (toffo @ rice dot edu). We look forward to seeing everyone at GEM and to your contributions. Frank Toffoletto, John Lyon, Pontus Brandt, and Vassilis Angelopoulos More information on the TIMI focus group can be found at: http://gem.epss.ucla.edu/mediawikiwiki/index.php/GEM_Focus_Groups

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2014 GEM Workshop : Tail Inner-magnetosphere interactions

The GEM focus group on Tail-Inner Magnetosphere Interactions will hold its breakout sessions on Tuesday June 17, 2014. We invite contributions to this session. More information on the focus group can be found at: http://gem.epss.ucla.edu/mediawikiwiki/index.php/GEM_Focus_Groups In addition to general contributions, we would like to invite participation from both modelers and observers in addressing two specific questions related to the physics of BBFs/dipolarization fronts:

1. How is the formation of the substorm current wedge related to BBFs/dipolarization fronts?
2. What is the physics of the oscillations in the field and plasma seen ahead of the front?

Andrei Runov has suggested two events that have a lot of observations, these are April 4 and 8, 2009. These events are well documented in recent papers (listed) below. If you are interested in participating, please contact the organizers.

We look forward to a productive session at GEM.

Vassilis Angelopoulos, Pontus Brandt, and John Lyon, and Frank Toffoletto,

Sergeev, V. A., I. A. Chernyaev, V. Angelopoulos, A. V. Runov, and R. Nakamura (2014), Stopping flow bursts and their role in the generation of the substorm current wedge, Geophys. Res. Lett., 41, doi:10.1002/2014GL059309. Sergeev, V.A., A.V. Nikolaev, N.A. Tsyganenko, V. Angelopoulos, A.V. Runov, H.J. Singer, J. Yang (2014), Testing a two-loop pattern of the substorm current wedge (SCW2L), J. Geophys. Res. Space Physics, 119, doi:10.1002/2013JA019629. Runov, A., V.A. Sergeev, V. Angelopoulos, K.-H. Glassmeier, H.J. Singer (2014), Diamagnetic oscillations ahead of stopped dipolarization fronts, J. Geophys. Res. Space Physics, 119, doi:10.1002/2013JA019384.

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2013 GEM Workshop : Tail Inner-magnetosphere interactions

The GEM focus group on Tail-Inner Magnetosphere Interactions will hold its breakout sessions on Monday - Tuesday, June 17-18, 2013. We invite presentations that specifically address one of the following topics:

• Origin and evolution of BBFs and related phenomena (bubbles, dipolarization fronts, etc.)

• The impact of BBFs et al on transport during different levels of activity (e.g., quiet times, SMCs, substorms, storm main phases).

• The impact of BBFs et al on the inner magnetosphere, including ring current and radiation belts; braking oscillations and micropulsations.

• Auroral streamers and other ionospheric signatures of BBFs et al.

More information on the focus group can be found at: http://gem.epss.ucla.edu/mediawikiwiki/index.php/GEM_Focus_Groups

We kindly ask presentations to be limited to 2-3 slides/5 minutes. If you would like to be put on the schedule, please contact Frank Toffoletto (toffo @ rice dot edu).

We look forward to seeing everyone at GEM and to your contributions.

Frank Toffoletto, John Lyon, Pontus Brandt, and Vassilis Angelopoulos

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2012 GEM Mini-workshop: Tail Inner-magnetosphere interactions

Location: Westin San Francisco Market Street, 50 Third St. San Francisco (Third Floor meeting rooms) – Cornell Room

From: John Lyon <lyon at tinman.dartmouth.edu> and Frank Toffoletto <toffo at rice.edu>

The GEM Tail inner magnetosphere interactions focus group will be having a meeting at the 2012 GEM mini-workshop on Sunday, December 2, from 2:30-4:30. Participants are invited to make a short presentation and to participate in the discussion and planning for the upcoming summer workshop. If you wish to make a presentation, please email us so we can put you on the schedule. We look forward to seeing you in San Francisco.