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HINODE Operation Plan (HOP)

accepted on


 HOP No.

 HOP title

HOP 0250

High speed flows associated with chromospheric transients in and around a sunspot

plan term

@ @


 name : Katsukawa, Otsuji, Tarbell
@  e-mail : yukio.katsukawa[at]nao.ac.jp

contact person in HINODE team

 name : Katsukawa @  e-mail : yukio.katsukawa[at]nao.ac.jp

 abstract of observational proposal
To capture very fast flows associated with chromospheric transients in an active region, such as Ellerman bombs and penumbral microjets, which is expected to be driven magnetic reconnection. This is realized by high resolution (0.2-0.3") spectroscopic observations of the chromospheric lines (by IRIS) and the photospheric lines (by Hinode SP).

Scientific Background:
We already know lots of transient events taking place in and around asunspot, such as penumbral microjets, jets above a light bridge,
Ellerman bombs, and chromospheric anemone jets (Katsukawa et al. 2007, Shimizu et al. 2009, Matsumoto et al. 2008, Shibata et al. 2007, etc.) We already have some examples of spectroscopic observations of Ellerman bombs and penumbral microjets at the Ha and CaII line by GBO (e.g. Reardon, Tritschler, Katsukawa 2013). These observations suggest magnetic reconnection take place in the upper photosphere or in the chromosphere though there are little knowledge on how fast flows is driven and how such flows influence the upper chromosphere and transition region.

Obtaining photospheric counterparts is also important to know magnetic field configuration at the roots of the chromospheric transients, such as penumbral filaments, emerging flux, and magnetic cancellation. It is also important to capture a signature of downflows from the magnetic reconnection (e.g. Katsukawa et al. 2010).

 request to SOT
- FG: BFI Ca II filtergram with the temporal cadence of 1.6 sec.
     * FG program 0x223 (FOV of 37"x87", 2x2sum)
       or FG program 0x414 (FOV of 42"x81", 2x2 sum)
 -> ~1200 Mbits/hour
- SP: Dynamics mode sparse scan of 10" with 1 minute cadence
     * 512 pixel (81") along the slit, no sum
     * step size 2, # of slit pos 32 (32x0.32" ~ 10")
     * # of cycles 2 (1.6 sec)
     * one side
     * repeat
 ->~900 Mbits/hour
   - Total: ~2.1Gbits/hour

Note: margin factor
  SP 0x15f --- 0.5

 request to XRT
Ti-Poly (or equivalent), larger than 256x256 1x1, 30-60 sec cadence (dependent on the telemetry allocation)

 request to EIS
YK_AR_50x384 (1" slit, 20sec exp, FOV 50"x384", duration ~20min)
Repeating the study for 2 hrs produces 17Mbits x 6 ~ 100 Mbits.

 other participating instruments
Request to IRIS: IRIS should run a high cadence (faster than 10 sec) single slit or 2-step sparse programs with the spectral windows containing Mg II h/k, C II, and Si IV. The FOV along the slit is 512 pix (85"). The Si IV and Mg II SJ images are useful for co-alingment with Hinode Ca II and also for capturing jets.

Target and duration:
The target is a well developed sunspot and its moat region. We'd like to locate the IRIS slit containing both a sunspot penumbra and the moat region.

We'd like to run the program to observe a sunspot located not only near the disk center but also away from the disk center (>30 deg).

The duration of the program is one hour which is limited by the telemetry allocation to SOT.

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