Magnetopause Reconnection and

PVI Enhancement

Ramiz A. Qudsi, Brian Walsh,

Boston University

*(qudsira@bu.edu)

(https://qudsiramiz.space)

Link to the presentation

Outline:

  • Magnetopause Magnetic Reconnection

 

  • Magnetic Partial Variance of Increments

 

  • Region of interest

 

  • Data and Methodology

 

  • Results and Discussions

Qudsi (qudsira@bu.edu)

The BASICS

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Source: NASA

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Reconnection at the Magnetopause

[Broll et al., 2017]

Source: wikipedia

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Inflow

Inflow

Reconnection at the Magnetopause

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Magnetic Partial Variance of Increments:

\mathcal{I}(t, \delta t) = \frac{|\Delta \mathbf{B}(t, \delta t)|}{\sqrt{\langle |\Delta \mathbf{B}(t, \delta t)|^2 \rangle}_{\mathcal{T}}}
\Delta \mathbf{B}(t, \delta t) = \mathbf{B}(t+\delta t) - \mathbf{B}(t)

Vector increment

Lag

averaging period

[Greco et al., 2008]

PVI < 3  ==> Maxwellian Plasma

PVI ~ 5-6  ==> Current Sheets

PVI ~ 6-8  ==> Reconnection Jets

So much in that excellent formula

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Magnetic Partial Variance of Increments:

[Servidio et al., 2011]

Demonstration of the effectiveness of identifying the reconnection locations using PVI technique

For threshold value larger than 5, the goodness of identification was found to be

~ 85%.

Region of interest:

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DATA and Methodology

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Data

Solar Wind data: OMNI (propagated to the magnetopause)

Magnetosheath data: MMS (FPI and FGM)

Magnetospheric magnetic field: Models (T96 and IGRF)

Magnetosheath magnetic field: Models (Cooling model)

GSM coordinate system

y

z

x

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Methodology

  • Look at the instances when MMS observed a jet reversal while crossing the magnetopause.

Qudsi (qudsira@bu.edu)

Methodology

  • Look at the instances when MMS observed a jet reversal while crossing the magnetopause.

Qudsi (qudsira@bu.edu)

V_{\rm p}
t
+ \Delta V
- \Delta V
|\Delta V |= 70\, km/s
|\Delta t | \leq 2\, minutes

[Broll et al., 2017]

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Magnetosheath

Magnetosphere

MMS data (FPI & FGM)

[Qudsi et al., 2023]

Jet Center

Methodology

  • Compute PVI for the 10-minute duration for each jet detection
  • Study the enhancements in PVI at and around the jet location

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  • Look at the instances when MMS observed a jet reversal while crossing the magnetopause.
\left< \Delta V_{L} \right> = \pm 70 km/s

Results and Discussion

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Qudsi (qudsira@bu.edu)

Qudsi (qudsira@bu.edu)

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Variation of ion-inertial length in and around the terrestrial magnetopause based on a combination of MHD and PIC simulations

[Toth et al., 2017]

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Concluding Remarks and Future Works

  • Enhancement in PVI is observed at the location of reconnection jets (for the case studies)
  • Is there a statistical correlation?
  • Can we use PVI as a proxy for reconnection?
    • What threshold of PVI?
    • Dependency on upstream solar wind conditions?
  • Is there a statistical correlation?