HOP 0500

contact person in HINODE team

name :

General: Kobelski, Duncan (NASA/MSFC) / Watanabe (NAOJ) / De Pontieu (LMSAL), SOT --DeRosa / Shine (LMSAL), XRT -- Reeves/ Testa (SAO)

e-mail :

adam.kobelski[at]nasa.gov, jessie.m.duncan[at]nasa.gov, tet_watanabe[at]jcom.zaq.ne.jp, bdp[at]lmsal.com, derosa[at]lmsal.com, shine[at]lmsal.com, kreeves[at]cfa.harvard.edu, ptesta[at]cfa.harvard.edu

abstract of observational proposal

Main Objective: High cadence multi-wavelength, multi-viewing angle observations of a flare

Scientific Justification: Solar Orbiter's upcoming flare campaign will provide high cadence, unsaturated observations of high energy flare processes in the corona (X-ray spectroscopic imaging & EUV imaging), chromosphere ((E)UV spectroscopy) and photosphere (optical light imaging and polarimetry). Coordination with Hinode and IRIS provides an opportunity to study these processes in similar energy bands from substantially different viewing angles and at all layers of the solar atmosphere.

request to XRT

We would like to request that XRT Be-thick is run in a fixed exposure mode, if possible. This is ideal for analysing flare time series on a high cadence. Based on discussions and recommendation from Lucas Guliano and Paola Testa, we would like to request this at a ~6 s exposure time, in order to optimise cadence but retain sufficient signal. From our perspective, the exposure can also be shorter than 6s (e.g. 2s) if that is preferable in order to ensure the safety of the CCDs, in the case of saturation. The major flare watch is targeting large flares so we think that there will be sufficient signal in the events of interest for such a short exposure time (of 2s).

If the proposed fixed exposure mode is deemed too risky for the safety of the instrument and/or the telemetry is limited we would like to request XRT is run in the same way as for HOP 476/489 with AEC 3.

request to EIS

We request that EIS run the Mg study "Rapid_Cadence_EIS_Flare_Stare" (acronym: FLAREDOP_EIS, study ID: 472, raster ID: 449) during windows 1 and 3. This was run in previous major flare campaigns (HOP 0456 + 0489).

We request that EIS run the existing flare study "FlareResponse_SitnStare" (acronym: FlareResponse04_sns, study ID: 651, raster ID: 623) during the Solar Orbiter major flare campaign during windows 2 and 4. This sit-and-stare observation mode includes several hot-lines clustered around logT = 6-7 taken at a 5s exposure. This will allow for high cadence composition and DEM analysis of the flaring region. Ideally, we would like EIS study coverage for the entire duration of this SOOP.

We would like to request that a slot raster (PRY_slot_context_v3 (ID 353)) is taken at the beginning and at the end of the observations, in all windows.

There are four instances of the major flare SOOP. During the first two (W1, W2: Mar 14th and 15th), Solar Orbiter will be near the Sun-Earth line. For the second two windows (W3, W4: Mar 30th and Apr 2nd), the spacecraft will be between 70-90 degrees from the Sun-Earth line. Therefore, the likelihood that Solo will point at an active region co-observed from Earth is higher during the first two windows so we would prioritise having the best possible coordination with EIS (and Hinode XRT and IRIS more generally) during the earlier windows. The first window is the longest (~7 hrs) so if study 472 is telemetry heavy and there is a tight budget, we have flexibility in terms of the ordering of the different modes. E.g. study 651 could alternatively be run during window 1 and 3 and 472 during windows 2 and 4.

We request that the EIS slit be positioned across a polarity inversion line, in a region likely to flare, in order to capture flare loops and ribbons, if possible. The pointing information for Solar Orbiter SPICE will be communicated - coordination of slit position is desirable.

other participating instruments

IRIS requests:
A request for high cadence IRIS observations has been submitted. The IRIS team have indicated that it should be possible to run in this mode for the windows requested.

SOOP: L_BOTH_HRES_HCAD_Major-Flare: LTP 19 - RSW 19 and 20
https://issues.cosmos.esa.int/solarorbiterwiki/display/SOSP/Solar+Orbiter+Planning+-+for+coordination+with+external+parties

remarks

Dates: 4 observation days, ~20hr in total
Window 1: 14.03.2025 16:10 - 23:10 UT
Window 2: 15.03.2025 12:00 - 16:10 UT
Window 3: 30.03.2025 11:00 - 15:30 UT
Window 4: 02.04.2025 05:00 - 09:30 UT

Time window: The solar Orbiter major flare campaign windows are as follows:
14.03.2025 16:10 - 23:10 UT
15.03.2025 12:00 - 16:10 UT
30.03.2025 11:00 - 15:30 UT
02.04.2025 05:00 - 09:30 UT
We would like to request continuous co-observations from Hinode for these time ranges, if possible.

Target(s) of interest: The same targets as for Solar Orbiter are required. This will be selected according to the active region thought most likely to flare. The EIS slit should be positioned across the PIL.

Previous HOPs:
I was not the PI of previous HOPs but this HOP is building on the previous major flare ones incl. 489, 476 and 456.

Additional remarks:
If Hinode would have difficulty supporting the entire SOOP intervals, particular priority should be given to windows 1 and 2 when Solar Orbiter is close to the Sun-Earth line.

Additionally, if the XRT fixed exposure mode is deemed too risky, the standard approach (AEC3) would also be desirable.