Seminars Autumn & Michaelmas Term of 2022

PLASMA SEMINARS AND GROUP MEETINGS

The style of the seminars will be informal/chaotic/interactive, following the established tradition. The format of the presentations can be a tutorial on a topic of interest, a report on just completed/ongoing/just starting/potentially interesting research projects, a literature review, a lecture by a passing visitor or anything else worthwhile that anyone cares to suggest. The speakers will be interrupted freely and asked to defend themselves. For background reading, only the most relevant or the most recent references are posted; please follow the paper trail from there. The schedule is subject to change on short notice, but what you see posted here is always up to date; the seminars are also announced via the department's seminar server (group meetings are not). Please email Alex Schekochihin if you would like to receive email updates on these seminars. "Plasma group meetings (or journal clubs)" will discuss current affairs (ongoing projects, new litearture etc.) as well as feature some presentations that are even more informal than seminars. They are open to all members of the Oxford Plasma Theory Group. While some expected contributions are pre-announced, everything is TBC and people wishing their work to be discussed can volunteer contributions without prior notice. Unlike for the seminars, there will not be full-spam-list email reminders of the group meetings. The seminars and group meetings are organised by Michael Barnes and Alex Schekochihin, please contact them with any queries or if you wish to present something.

Past seminar database: Autumn 2007; Winter-Spring 2008; Summer 2008; Autumn 2008; HT 2009; TT 2009; Summer 2009; MT 2009; HT 2009; TT 2010; Summer 2010; MT 2010; HT 2011; TT 2011; Summer 2011; MT 2011; HT 2012; TT 2012; Summer 2012; MT 2012; HT 2013; TT & Summer 2013; MT 2013; HT 2014; TT & Summer 2014; MT 2014; HT 2015; TT & Summer 2015; MT 2015; HT 2016; TT & Summer 2016; Autumn/MT 2016; HT 2017; TT & Summer 2017; Autumn/MT 2017; HT 2018; TT & Summer 2018; MT 2018; HT 2019; TT & Summer 2019; MT 2019; HT 2020; TT & Summer 2020; MT 2020; HT 2021; TT & Summer 2021; Autumn/MT 2021; HT 2021; TT & Summer 2022;

Autumn & Michaelmas Term of 2022

The seminars/group meetings will be on Tuesday at 14:00 in the Simpkins Lee Room, Beecroft Building, except where indicated otherwise below, in red.
It will be possible to join these meetings (when they are held in SL Room) on ZOOM --- details available from Alex on request.
Those who join these meetings on ZOOM are asked keep their video cameras on.
The ZOOM system in Simpkins Lee Room does not display a list of participants whose cameras are off. It is not germane to these informal meetings to have invisible listeners of whom those present in the room are unaware, so if you are unable or unwilling to turn on your camera, you cannot join the meeting.
Here is a list of all Physics seminars.

If you know exactly what you are going to do, what is the point of doing it? Pablo Picasso
He goeth furthest who knows not whither he is going. Oliver Cromwell

Every line in your calculations ends with "=0". You are not making much progress! Kate Hammett
We don't do the calculation because we don't know the answer, we do it because we have a conscience. Bryan Taylor
Let's change the resolution on the Unknown. Gabe Plunk
Working together takes more than one person. Bill Dorland
We can't do ultraviolence to that square bracket. Ian Abel
Field lines are forever. Bryan Taylor
This is not really an ill-posed problem, this is not a problem at all. Paul Dellar
I am just doing mathematics at the moment, but it is mathematics that has some point. Bryan Taylor
The equivalent of God in MAST is MHD, which is global and all-powerful. Anthony Field
We have crossed all the i's and dotted all the t's. Job's a good'un. Ian Abel
Let us not jump in front of the bandwagon! Alex Schekochihin
It's not the triviality, it's the emptiness of it that bothers me. Bryan Taylor
Never take 0 for an answer. Alex Schekochihin
This is a very inefficient way of achieving nothing. François Rincon
For the sake of fairness, let me mention that some people have objections to this, none of which are particularly valid. Chris Chen
This is more or less right. Perhaps less. Alfred Mallet
Too simple? At the end of my talk, you will beg for simplicity! Andrey Beresnyak
What is the point? The point is not the point! Anonymous
This is why I am presenting this here and nowhere else: nothing is solved! Ian Abel
Previous studies of this problem have been either unsatisfactory or limited in scope.---What is the difference between these?---This means either wrong or irrelevant. Anatoly Spitkovsky, Michael Medvedev & Steve Cowley (in conversation)

I don't give a damn about astrophysics, explain to me what is going on. Anatoly Spitkovsky

It is better to be vaguely right than exactly wrong. Carveth Read (usually attributed to Maynard Keynes)

Have you subtracted the baby with the bathwater? Steve Balbus
This is not rigour, unless you mean rigor mortis. Ian Abel
I wouldn't say these are theoretical arguments... Let's just call them arguments. François Rincon
This qualitative explanation is not of sufficient quality. Eugene Churazov
If you mean it seriously, this is actually a very good question. Minhyong Kim
This paper is a tour de farce. Ian Abel
What is modelling? You run a simulation, you compare. If it coincides, great! If it doesn't coincide, fuck! Felix Parra
I have seen papers where the student wasn't the problem. Michael Hardman
There has been a lot of fascinating work on this subject, most of it kind of boring. Philipp Kempski
So now you want us to drop everything we are doing and start worrying about what the big questions are?! Ian Abel
Oh dear, I thought I had some conclusions. Nuno Loureiro
I've got my little fingers inside this plasma. Steve Cowley
Words will play a big role in this talk. Dmitri Uzdensky
Everything that can be done should be done---and that's the astrophysical attitude. Michael Medvedev
What I will talk about is not low-hanging fruit. A lot of people have looked at this. There is no fruit here at all.---What about sour grapes? Michael Medvedev & Nuno Loureiro
In order to have a disappointment, you first have to have an appointment. Alex Schekochihin
In our experiment, we observed strong absence of magnetic energy. Archie Bott
Much as I somewhat hate this approach... Peter Davidson
Your infinity is my zero. Mantas Abazorius
If I had known the outcome of this calculation, I would never have done it. Michael Hardman

Now that everyone knows this is the new Pandora's box, they are all going to jump into it. François Rincon

[these quotes are mostly from these seminars and the Vienna meetings]

Wk	Date	Time & place	Speaker & Topic	Background reading	Visitors in town
	Tue 30 Aug	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Journal Club. (organised by ALEX) Michael Hardman will lead the discussion of the preprint by A. Volcokas et al. "Ultra-long turbulent eddies, magnetic topology, and the triggering of internal transport barriers in tokamaks"	arXiv:2208.06159 also see arXiv:2208.02202 arXiv:2208.11984
	David Hosking leaves the group to take up a postdoctoral Fellowship at PCTS, Princeton (and a JRF at Gonville & Caius College, Cambridge) Silvia Trinczek leaves the group to continue her PhD with Felix Parra at Princeton
	Tue 6 Sept	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Hanne Thienpondt (CIEMAT) --- Turbulent transport avoids core particle depletion in stellarators		Jose Manuel Garcia Regaña Antonio González Jerez Hanne Thienpondt (CIEMAT) Linda Podavini Sven Stroteich (Greifswald)
	Mon 12 Sept	11:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Raul Gerru Miguelañez (DTU) --- Study of the origin of the electric field in toroidal magnetised plasmas		Raul Gerru Miguelañez (DTU) Antonio González Jerez Hanne Thienpondt (CIEMAT) Linda Podavini Sven Stroteich (Greifswald) Nick Schwartz (Maryland)
	Tue 13 Sept	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Linda Podavini (Greifswald) --- Gyrokinetic instabilities and turbulence in stellarators	PRE 106, L013202 (2022) PRL 127, 155001 (2021)
	Tue 20 Sept	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Denis St-Onge --- Update on global effects in GK simulations
	Tue 27 Sept	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Georgia Acton --- Optimising for gyrokinetic microstability using adjoint method	report from author on request
0	Michael Hardman leaves the group to take a research staff post at Tokamak Energy Ltd, but remains a long-term visitor Archie Bott (formerly postdoc at Princeton) joins the group as a UKRI Future Leaders Fellow, based in ALP Juan Ruiz Ruiz, currently a TDoTP PDRA, is reborn as an independent EPSRC Postdoctoral Fellow Nick Lopez (formerly PhD student at Princeton) joins the group as a postdoc to work with Alex Schekochihin & Gianluca Gregori Leonard-Petru Turica (formerly MMathPhys student) joins the group as a DPhil student to work with Alex Schekochihin & Anthony Field
0	Tue 4 Oct	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Juan Ruiz Ruiz --- Progress report on the interaction between fast-particle-driven Alfven eigenmodes and drift-wave turbulence
I	Tue 11 Oct	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Mantas Abazorius --- Update on SOL physics in tokamaks
II	Tue 18 Oct	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Nick Schwartz (Maryland) --- A 0D solver for centrifugal mirrors The centrifugal mirror confinement scheme incorporates supersonic rotation of a plasma into a magnetic mirror device. This concept has been experimentally shown to drastically decrease parallel losses and dampen instabilities as compared to classical mirrors. MCTrans++ is a 0D steady-state scoping tool which rapidly models experimental operating points in the Centrifugal Mirror Fusion Experiment (CMFX) at the University of Maryland. In the collisionless regime, the losses agree with Pastukhov, and the confining potential is due to both an ambipolar and centrifugal potential, whereas the perpendicular losses are classical. Radiation losses such as Bremsstrahlung and synchrotron are accounted for. A neutrals model suggests that the dominant energy loss is through charge exchange. Equilibrium is found with the SUNDIALS ARKODE package, and has two methods of solving --- fixed voltage and fixed temperature. The software is also suitable for use in a non-linear optimizer, and can be operated with time-dependence, representing a capacitive discharge, for example. This transport code has been used to verify results from prior centrifugal mirrors, create an experimental plan for CMFX, and find configurations for reactor-scale fusion devices.	PoP 8, 2057 (2001) NF 14, 3 (1974) PRL 87, 235002 (2001)	Nick Schwartz (Maryland)
III	Tue 25 Oct	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting. (organised by ALEX) Michael Nastac --- Kinetic passive scalar turbulence in electrostatic plasmas	RMP 73, 913 (2001) JPP 84, 905, 840107 (2018) +preprint from author on request	Hantao Ji (Princeton)
IV	Tue 1 Nov	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Juan Ruiz & Toby Adkins --- Memoirs of the APS DPP Meeting in Spokane
V	Tue 8 Nov	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Archie Bott --- Update on latest dynamo experiments on the Omega laser	background: PNAS 118, e2015729118 (2021)	Jun Lau (UCL)
VI	Tue 15 Nov	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Journal Club (organised by ALEX) Plamen Ivanov will discuss Tirkas et al. "Zonal flow excitation in electron-scale turbulence", arXiv: 2211.02140 Michael Hardman will discuss Roberg-Clark et al. "Reduction of electrostatic turbulence in a quasi-helically symmetric stellarator via critical gradient optimization", arXiv:2210.16030		Jun Lau (UCL)
VII	Tue 22 Nov	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by MICHAEL) Yujia Zhang --- Fluid model for ITG turbulence with electromagnetic effects in a Z pinch	JPP 88, 905880506 (2022) JPP 88, 905880410 (2022) +write-up from author on request	Peter Davidson (Cambridge) J-B Fouvry (IAP) Chris Hamilton (IAS Princeton) Christophe Pichon (IAP) Mathieu Roule (Ecole Polytechnique)
VIII	Tue 29 Nov	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ARCHIE) Will Clarke --- Ion-scale electromagnetic turbulence driven by electron-temperature gradient	JPP 88, 905880410 (2022) +write-up from author on request	Chris Hamilton (IAS Princeton) Mathieu Roule (Ecole Polytechnique)
9	Tue 6 Dec	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by JUAN) Nathan Belrhali --- Extension and limitation of Gaussian beam tracing for wave propagation in anisotropic media and application to critical cases near caustics	preprint from author or Juan on request	Nathan Belrhali (ENS Paris) Chris Hamilton (IAS Princeton)
10	Tue 13 Dec	No seminar
	Tue 20 Dec	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Leonard Turica --- Update on modelling ETG transport in JET-ILW pedestals + Juan Ruiz Ruiz will lead a Journal Club discussion of Belli et al. "Spectral transition of multiscale turbulence in the tokamak pedestal"	NF 62, 086028 (2022) PoP 29, 062501 (2022) +preprint from A. Field on request
	Tue 27 Dec	No seminar

Hilary Term of 2023