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828 03-Feb-2017 10:35 18 KB Denver to previous The line's engaged cena anafranilu Minter is now trying his hand at headhunting

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EDL: the magnetic (prominence) bubbles - is it the MHD, HD?
TB: BC Low believes it's a solenoidal knot field emerging and then rising up into the equilibrium of the cavity. I'm convinced it's also thermal, that it's hotter. Neal Hurlburt is now simulating this as a concentrated field and it doesn't rise unless he heats if first.
EDL: it looks like a radiative interface.
TB: Yes, it's a plasma pile-up I think, cos you see the plasma falling down and stopping on the rim. It's one of the main goals of the SUMER campaign in April.
Karin: how large
TB: about 50 Mm, and they live for an hour or more, so we'd have to get very lucky, to scan SUMER across it. Could get readings in TR lines.
If it's a purely thermal effect, the speed of the rise indicates a certain temperature rise.
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!What was SOT looking at...?
Knowledgebase
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If you have a particular date in mind, it's very easy.
''SunGate portal looks like just the thing we were talking about yesterday.''
* Reduction
Shutterless mode for really fast Stokes parameters is possible but takes a little more work.
Because a lot of the SOT datasets are very large. So rather than reading it all into memory, you can tell it to read in a filelist, then dump the output to disk.
SP: L0 is the raw reformatted 4D data. Mostly just reading one side of the CCD now.
[http://sot.lmsal.com/data/sot/level1d] means you never have to run SP_PREP(!). Just go there for SP data.
KPD: what's the noise level in these data?
TB: 2 - 5 gauss.
For QS, we can now tel you the QS field with rapid scans across a small area 10x164" would take just minutes, depending on sensitivity. Can also shorten the slit if necessary.
SOME level 2 data are online at http://sot.lmsal.com/data/sot/level2 - they are calibrated IN GAUSS.
Can take these data and make a vector field if you want.
Lastly, I note that we have the SOT analysis guide and it includes the Paris Tutorials on certain datasets, including SP_PREP if the data centre each
Bruce probably has a tool he can give you to get Bx, By, Bz.
EDL: notwithstanding the 180º issue.
TB: MERLIN code has
KPD: the inclination is to the LS
Shutterless
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* HEM would be interested to put together a joint EIS XRT temperature distribution. (XRT: Reeves, Narukage; EIS: Warren, Mason)
(multi-filter data required; perhaps during SYNOP006? Could consider taking semi-regular datasets in co-ordination with this)
"hot stuff" can be done with another set of data.
* LKH thinks there’s a disconnect between horizontal magnetic fields
o EIS could potentially do something there WHADDAYA WANT?
temperature ranges of plasma observed in response to this emergence. Hot reconnection sites low down? Rapid cadence with a large temperature spread. Can be almost granule-sized, so detectable XRT/EIS. KM's programme in the QS might be suitable if there are SP data. XRT: taking long exposures with XRT to saturate on the bright points: ~40s Al_thin, exposing for everything else.
TB: HOP 89 study.
XRT: Paolo Grigis; EIS: Karin Muglach
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* GAD: SOT discovered spicular material that‘s moving at very high velocity
Type I and II
I ordinary:
II straws:
Look for events in EIS and XRT that overlap with SOT discoveries: look for the most dynamic stuff in EIS. Trigger is an SOT event.
Take emerging flux, etc., and ..... look in EIS & XRT data for response.
Spicules -- disappearance of the H-alpha spicules: is it thermal? can we measure where that happens? Need to consider the dynamical timescales, observed off-limb. TJW: SUMER has observations in Si III (SOT: Bart de Pontieu; EIS: Hansteen; )
ISSI Meeting in Jan had this as a major topic.
Lingangan ApJ 679 L167 good place to look up, too.
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* JTM we have great difficulty at getting quantitative information
o JLC is the filter ratio method working quantitatvely
+ think the XRT filter ratio people have confidence, but when you compare that with EIS
o JTM: I just want to know where the hot plasma is
o JLC: if you see it at all in XRT, it‘s hot, but that‘s qualitative
o HPW in principle should be able to put these things together. We w
If you want to look at hot structure, DEM aside, Narukage. More general point, disappearing filaments: are they heated, if so how? Simple filter ratios enough. What happens in EIS and XRT when photospheric features vanish/change.
14th Mar 09: XRT sees post-eruption loops (see XRT POW page on main webpage.)
(XRT: Narukage & for filament disappearance, Y Su; SOT: H-alpha & B field, Berger; EIS: JLC, Green, Tripathi)
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* LKH: Outflow areas: what does Ca II H look like?
EIS: Young, Doschek, Harra; XRT: Korreck, SOT: Berger – see HOP 96
H-alpha vels on disc, blocking filter band is shifted, so you get contin contamination and unreliable vel's. But off-limb okay. Near limb AR might be okay, with SOT looking just off limb at the chromosphere. Most of the data applicable would be prominence observations.
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* HPW: could SOT provide a measure of the vector magnetic field
Any updates on Karel S. does with extrapolations? Not since Boulder.
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* HPW: think we should do what Helen has done and get cross-calibrated joint observations
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* HEM: cores of active regions: high temperatures. XRT: highly transient structures rule out multi-filter observations. AEC defeats you, so... one filter has a greater chance of working. Looks like the distinct discussion groups need to be integrated. XRT: Grigis, Korreck, McCaughey; EIS: Mason, Ugarte; SOT: Tarbell). XRT would now do single-filter at high cadence, with a filter that's moderately thick.
TJW: SUMER sit'n'stare; at loop top, it may be worth plonking EIS there to look for slow-mode oscillations at high T in flaring loops.
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EDL: Diagnostics from the slots?
Density diag's could be feasible.
The jets' thermal structure, can it be derived? But density useful, too, because of the ionisation balance range. LKH: It may also be possible to derive velocities, too. (EIS: Sun, Harra; XRT: Savcheva, DeLuca; SOT:
Look to get EIS to look at one set of parameters and XRT to look at its main strengths.
SP Scans at south pole show good signal (exp. time unsure); DHB: H-alpha at the poles?;
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* TB: Coronal cavities; S. Gibson & D. Schmidt, multi-day campaign was run: needs an EIS mentor: EIS: Tripathi; no SOT component, nothing much to see ≥30" above limb.
see HOP 114.
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* Prominence bubbles (HOP 73):
EIS: Brooks; SOT: Berger;
Bubbles are short lived, but would be good to go back over the older data.
XRT: boundary? TB: Cavity-appropriate studies. When bubbles go through the prominence, what happens?
EDL: are the cavities tied in or tied around? TB: around; recon events inject material? There may be a mass drainage route into the PIL.
If the bubbles are intermittent, they should be on the disc, too. Look at filaments for intermittent velocity events. May not be able to see the upflows directly with SOT, but it might be possible with EIS.
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How to prioritise the requests about Active Regions, Flares, etc.
Use the flare flags, Be_Thin to control saturation...
T.Sh.: Strong TLM constraints, but a v. important target.
Want more widely applicable studies, in terms of the number of science questions you could address. Last Sep's SWG tasked small groups to discuss the most suitable observing programmes for ARs and Flares.
There are 6 or 7 standard sequences suitable for B field evolution in ARs; as well as for major flares. (for SOT, this is).
But for EIS, XRT...
We're typically operating as an observatory, responding to multifarious requests. When we've an AR, there are many conflicts between these and core programme desires. Energetic ARs may trigger another observing mode, where we concentrate on this kind of target. Need several standard programmes.
EDL: Had to demonstrate the XRT could respond to the flare flag in a timely manner. Demonstrated now.
DHB: will probably test the EIS internal flare flag, too. Maybe triggering off He II first.
HPW will forward what we have so far to the EIS team.
Good to announce this mode first so that people are aware of the sensitivity to busy active regions.
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**Ted Tarbell
**Ted Tarbell ''(unable to attend)''
This page (revision-828) was last changed on 03-Feb-2017 10:35 by DenverTop