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HINODE Operation Plan (HOP)

accepted on

21-Oct-10


 HOP No.

 HOP title

HOP 0176

High Resolution Multi-Wavelength Study of Small-Scale Jets on Solar Disk

plan term

2010/11/19-2010/11/29
2011/11/09-2011/11/18

@ @

proposer

 name : Denker, Wang, Deng @  e-mail : cdenker[at]aip.de

contact person in HINODE team

 name : Shimizu @  e-mail : shimizu.toshifumi[at]isas.jaxa.jp

 abstract of observational proposal
Small-scale dynamics in the quiet Sun play an important role in coronal heating and mass transport for the solar wind. In particular, jets, mostly in the form of spicules, may be responsible for carrying energy and momentum sustaining heating and flows. The recent discovery of type II spicules is of particular importance due to their high speed, rapid heating, and large vertical extent. About a decade ago, a new kind of jets was identified on the solar surface using fast spectrograph scans obtained at Big Bear Solar Observatory (BBSO). They were named as the "H-alpha Upflow Events" (Chae et al. 1998; Lee et al. 2000). Using more recent observations, a few researchers found similar features and named them "Rapid Blueshifted Excursions" (RBEs; Langangen et al. 2008). It is highly probable that Upflow Events (or RBSs) are the disk counterparts of type II spicules on the limb. However, discrepancies between them, especially in the detected speed, exist and need further exploration.

We propose to carry out a coordinated observing run using Hinode and the Vacuum Tower Telescope (VTT) at the Observatorio del Teide, Tenerife, Spain to quantitatively study small-scale jets on the solar disk in both the quiet Sun and active regions. We will observe with the VTT high-resolution spectrograph simultaneously the chromospheric H-alpha and photospheric Fe I 709.0 nm lines to study the properties (velocity, density, temperature and statistical distribution) of these small-scale ejections and associated heating. Using high-resolution vector magnetograms from Hinode/SP, the photospheric magnetic structure and evolution associated with these features will be investigated. In particular, the magnetic reconnection at small scales will be characterized. The corresponding counterparts of those jets in the transition region and corona will be investigated using EIS and XRT observations. We will study their vertical extent, mass flow propagation, and heating processes. We will chose a small FOV within quiet Sun regions inside and outside coronal holes as well as in active regions that may produce microflares.

References:
Chae, J., Wang, H., Lee, C.Y., Goode, P. R. & Schuehle, U., 1998, ApJ, 504, 123
Lee, C.Y., Chae, J. & Wang, H., 2000, ApJ, 545, 1124
Langangen, O. et al. 2008, ApJ, 679, L167

 request to SOT
~1710 Mbits/day

Combination of SP and FG observation with SP as first priority. The observing procedure is the same for every day during the  coordinatedobserving run.

Only the target will change (4 days active region, 3 days each for quiet Sun observations within and outside of a coronal hole as close to disk center as possible).

SP: ~400 Mbits/hr, 1200 Mbits/day

Context SP IQUV scan (fast map, for 64" x 123", 0.32" slit, 14 min) at the beginning and end of the coordinated high cadence observing run.

Continuous high cadence SP IQUV scans (fast 32" x 123", 0.32" slit, 7 min cadence) during the coordinated observation.

FG: ~170 Mbits/hr, 510 Mbits/day
Ca II H and G-band image sequence during coordinated observation
(2-minute cadence, 111" x 111" FOV, 2 x 2 pixel binning).


 request to XRT
~10 Mbits/hr, 30 Mbits/day

Ti/Poly images, 192" x 192" in minimum to completly cover the SOT FOV (larger size is welcome, if telemetry permits), 1"-resolution,cadence 1 min, Q=95 or better compression, run during the coordinated observation. Include G-band exposures in very low cadence for alignment purpose. Full-Sun context at the beginning and end of each day coordinated observing run.

 request to EIS
~20 Mbits/hr, 60 Mbits/day

EIS Context

OBJECTIVE: Observe the same FOV (60" x 100") as SP and VTT context for alignment.
TARGET: Active region (4 days), quiet Sun within a (3 days) and outside of a (3 days) coronal hole.

POINTING: Align EIS FOV with SOT/SP.
SLIT: 2"
STEP SIZE: 2"
EXPOSURE TIME: 20 s
RASTER: Scanning
RASTER DURATON: 10 min
FOV: 60" x 100" same as SP and VTT context.
DATA COMPRESSION: DPCM or JPEG75 or JPEG90
DATA VOLUME: ~3.2 Mbits

Do EIS context raster scan once at the beginning and once at the end of each coordinated observing run, same as SP and VTT context.
SPECTRAL WINDOW: 10
LINES: He II, O V, Si VII, Si X, Fe XII, XIII, XV, XVI, XXIII


EIS high cadence run

OBJECTIVE: Observe with a 5-minute cadence the same area (30" x 100") as SP and VTT high cadence, to measure flows, electron densities and temperatures in jets.
TARGET: Active region (4 days), quiet Sun within a (3 days) and outside of a (3 days) coronal hole.

POINTING: Align EIS FOV with SOT/SP.
SLIT: 2"
STEP SIZE: 2"
EXPOSURE TIME: 20s
RASTER: Scanning
RASTER DURATON: 5 min
FOV: 30" x 100" same as SP and VTT high cadence
DATA COMPRESSION: DPCM or JPEG75 or JPEG90
DATA VOLUME: ~1.6 Mbits

Repeat raster scan for about 2.5 hrs (same as SP high cadence). Run
simultaneously and co-pointed with the high cadence SOT/SP program.

SPECTRAL WINDOW: 16
LINES: He II, O V, Si VII, SiX, Ca XVII, Fe VIII X, XI, XII, XIII, XIV,
XV, XVI, XVII, XXIII, Fe XXIV
Considering that jets are expected to have high densities, the Fe XII
186/195 and Fe XIII 196.6/202 ratios are included to measure them.

Other participating instruments

VTT high-resolution spectrograph and adaptive optics (AO). Raster scans will be performed simultaneously in the chromospheric H-alpha and photospheric Fe I 709 nm lines (100" x 100" FOV at the beginning and end of the coordinated observing run and 30" x 100" FOV during the remainder of the time, 0.3" slit, 3.5 min cadence). Chromospheric full-disk images (Ca II K, H-alpha, He I 1083 nm, 2k x 2k pixels) will be provided by ChroTel (Kentischer et al. 2008, Proc SPIE, 7014, 701413).

 other participating instruments
VTT high-resolution spectrograph and adaptive optics (AO). Raster scans will be performed simultaneously in the chromospheric H-alpha and photospheric Fe I 709 nm lines (100" x 100" FOV at the beginning and end of the coordinated observing run and 30" x 100" FOV during the remainder of the time, 0.3" slit, 3.5 min cadence). Chromospheric full-disk images (Ca II K, H-alpha, He I 1083 nm, 2k x 2k pixels) will be provided by ChroTel (Kentischer et al. 2008, Proc SPIE, 7014, 701413).

 remarks
[Time period] 2010/11/19-2010/11/29.

We request Hinode support for 3 hours of observing time on 10 days (which could be dropped to seven (3+2+2) days) during the time window specified below. Observations on consecutive days are desired, but not necessary. Like other ground-based HOPs, it requires fairly high priority until some good data is obtained at Tenerife, then priority can drop down. We will inform the Hinode teams well in advance about the local weather conditions

Contact person: Carsten Denker, e-mail: cdenker@aip.de, phone: +49 331 7499 297 (office in Potsdam, Germany) and +34 922 329 142 (VTT Tenerife).

[Time window] The best seeing conditions at Tenerife are from 9-12 UT in November. Continuous observations within that time window are requested to cover the temporal evolution of jets and microflares.

[Target] An active region centered on a pore or small sunspot would be the preferred target. In absence of any active region we would like to observe a quiet Sun region within or outside of a coronal hole.  Carsten Denker will specify detailed pointing and inform Hinode team every day.

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