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HINODE Operation Plan (HOP)

accepted on


 HOP No.

 HOP title

HOP 0035

DST/IBIS, Hinode/EIS+SOT+XRT, SOHO/MDI and TRACE -Magnetic helicity in active filaments

plan term


@ @


 name : Romano, Battiato, Zuccarello, Contarino, Guglielmino @  e-mail : prom[at]oact.inaf.it

contact person in HINODE team

 name : T. Sekii
J. L. Culhane
@  e-mail : sekii[at]solar.mtk.nao.ac.jp

 abstract of observational proposal
We want to investigate whether the conditions for filament eruption occurrence depends on the shear / twist of the filament magnetic field or on the interaction between the highly sheared core field of the filament and the overlying flux rope. In this context, two main theoretical models have been proposed. The former suggests that the magnetic eruption and the impulsive energy release begins deep in the highly sheared core field of the filament and the overlying flux rope then erupts into interplanetary space (Moore et al., 2001). The latter assumes that a sheared core field pushes through an overlaying restraining filed and that a slow reconnection begins at a neutral point high in corona. After the restraining force of the overlaying field significantly weakens because of the reconnection, the sheared core field explosively erupts into interplanetary space (Antiochos, 1998). We think that the measure of the magnetic helicity or of its flux from the photosphere into the filament axis and the study of the magnetic topology of the active region where the filament eruption occurs, will give us the opportunity to discriminate between these two theoretical models.

 request to SOT
SOT: we plan to run in time a sequence of 3 exposures: 2 using the BF imager and 1 using the SP.
SOT/BF: G-band and CaII H filtergrams, cadence: 10 s per filtergram FOV: 218hx209h (2k x 1k mode, binning 2x2 pxs).
SOT/SP: Sequence of scans in Fe I 630.2 nm using the Normal Map mode.

 request to XRT
XRT: middle cadence of the images is required using thin Be filter, exposure max of 1 s, cadence of 1 min, no binning and loss-less compression data.  

 request to EIS
EIS: measurements are proposed using the prepared raster acronymed as eRomanof. It has been specified using the EIS study template and the corresponding romano_1.DEF file which is already sent to the EIS SSC L. Culhane.

 other participating instruments

SOHO Observations:  Our request of MDI support concerns the possibility of obtaining high resolution magnetograms during the period of IBIS observations. They are crucial in order to get information on the magnetic configuration and the emerging magnetic flux in the examined region. We are interested on full MDI HR FOV. A cadence of a HR magnetogram every 5 minutes would be recommended.    

TRACE Observations:   A cadence of high resolution (768 x 768) 171 A and/or 195 A images every 30 sec of the active regions selected day by day would be recommended. One WL image every hour for the co-alignment with other instruments data would be also recommended.

Contact  Paolo Romano: email: prom@oact.inaf.it, tel.: +39 095 7332 220, fax.: +39 095 330592
Francesca Zuccarello: email: fzu@oact.inaf.it, tel.: +39 095 7332 237, fax.: +39 095 330592
Lidia Contarino: email: lcont@oact.inaf.it, tel.: +39 095 7332 244, fax.: +39 095 330592
Salvatore Guglielmino: email: sgu@oact.inaf.it, tel.: +39 095 7332 330, fax.: +39 095 330592
Viviana Battiato: email: vbat@oact.inaf.it, tel.: +39 095 7332 206, fax.: +39 095 330592

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