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tags: diagnostics, langmuir, minutes
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# PlasmaPy Langmuir Meeting | Monday 2020 November 30 at 11:00 PT / 14:00 ET

[](https://hackmd.io/vkw0IQYKRWCsFgbYpPMGMw)

### Video Conference Information
* Instant messaging: [Matrix](https://element.im/app/#/room/#plasmapy:openastronomy.org) and [Gitter](https://gitter.im/PlasmaPy/Lobby)
* [GitHub Minutes Repository](https://github.com/PlasmaPy/plasmapy-meeting-notes)
* [Langmuir Sub-directory](https://github.com/PlasmaPy/plasmapy-meeting-notes/tree/master/langmuir_2020-present)
* [PlasmaPy on GitHub](https://github.com/PlasmaPy/plasmapy) ([pull requests](https://github.com/PlasmaPy/plasmapy/pulls), [issues](https://github.com/PlasmaPy/plasmapy/issues))
* [PlasmaPy Enhancement Proposals on GitHub](https://github.com/PlasmaPy/PlasmaPy-PLEPs)
* [PlasmaPy Google Calendar](https://calendar.google.com/calendar?cid=bzVsb3ZkcW0zaWxsam00ZTlrMDd2cmw5bWdAZ3JvdXAuY2FsZW5kYXIuZ29vZ2xlLmNvbQ)
* GitHub Project: [Prototype | Analysis, Diagnostic, and the Swept Langmuir](https://github.com/PlasmaPy/PlasmaPy/projects/19)

## Attendees

1. Erik
2. Steve

## Action Items

**copy action items from last week**

***Erik***
* Open PR to update fit_function Linear.root_solve that handles `m = 0` and `b = 0` cases
* Finish writing tests for `find_floating_potential()`
* Add to list of functionality the ability to find `Te` from fitting to the left side of the dI/dV peak.

***Gurleen***
* Implement a prominence "uncertainty" for `vp` inf `find_plasma_potential_didv()`.
* for "uncertainty" will use FWHM of the peak
* also report the prominence of the peak

***Future***
* open an issue to construct a metric that considers the signal noise when reporting the peaks "prominence" (`find_plasma_potential_didv()`)

## Agenda (please feel free to edit or add items)

1. Introductions
2. GitHub Project: [Prototype | Analysis, Diagnostic, and the Swept Langmuir](https://github.com/PlasmaPy/PlasmaPy/projects/19)
3. ...
4. ...
5. Issues
1. ...
2. ...
6. Pull requests in progress
1. [PR #889](https://github.com/PlasmaPy/PlasmaPy/pull/889): calculating floating potential
2. [PR #897](https://github.com/PlasmaPy/PlasmaPy/pull/897): plasma potential via dI/dV
3. [PR #813](https://github.com/PlasmaPy/PlasmaPy/pull/813): Langmuir & Diagnostic Framework

## Minutes

* lots of pie was consumed over the last week
* getting Te from fitting to the left-side if dI/dV vs. V was brought up again
* This has seen recent success on fitting curves associated with LaPD's cathode upgrade
* knappmiller2006 - DOI: https://doi.org/10.1103/PhysRevE.73.066402
* fitted parameter from this approach could be used to approximate `n_e` (assuming gaussian)
* Priority of functionality:
1. floating potential
1. ion-saturation
1. plasma potential via dI/dV
1. Te from left side of dI/dV
2. Te from linear of log(I) vs. V
3. plasma potential from two linear intersection (i.e. electron exponential and electron saturation)
4. ...