HOP 0332

HINODE Operation Plan (HOP)

accepted on

22-dec-2016

HOP No.

HOP title

HOP 0332

Active region jet studies with Hinode and IRIS

plan term

ToO
2017/02/14-2017/03/03

proposer

name :

Mulay, Del Zanna, Mason

e-mail :

smm96[at]cam.ac.uk, gd232[at]cam.ac.uk, hm11[at]cam.ac.uk

contact person in HINODE team

name :

Culhane

e-mail :

j.culhane[at]ucl.ac.uk

abstract of observational proposal

Main Objective: To study the relationship between cool and hot component present in Active region jets using EIS, IRIS and XRT observation

Scientific Justification: Solar jets are recurrent transient events that have been observed near the edge of active regions (AR jets). Their lifetime is order of few minutes and the recurrent activity can last for few hours.
The temperature distribution of AR jets has been studied with UV (Mulay et al. 2016a) and X-ray imaging observation (Paraschiv et al. 2015). Simultaneous imaging and spectroscopic observation of these events can give us a better estimate of their physical parameters.
However, solar AR jets are very dynamic events and it has always been a challenge to observe them simultaneously with imaging (UV-X-ray) and spectroscopic (UV) instruments. Nonetheless, Mulay et al. (2016b) recently found one Hinode/EIS observation of recurrent AR jets in the archive data set and reported some interesting results about the temperature and density structure. They reported high electron densities (log Ne > 11.5) in the jet footpoint region which are found to be above the sensitivity of the Fe XII lines ratio diagnostics. The low (log T < 5.8) and high temperature (log T > 6.4) coverage was lacking in those EIS observations and hence there wasn't a good constraint on the EIS DEM analysis in that temperature range.
They reported high electron densities (log Ne > 11.5) in the jet footpoint region which are found to be above the sensitivity of the Fe XII lines ratio diagnostics. The low (log T < 5.8) and high temperature (log T > 6.4) coverage was lacking in those EIS observations and hence there wasn't a good constraint on the EIS DEM analysis in that temperature range.
Also, the AR jets observations showed high temperature emission from the Fe XVIII (93.932A) lines estimated from the AIA 94A channel (Del Zanna (2013)) in the region of the footpoint. A study of the temporal evolution of the footpoint region confirmed the hot component was present initially, but that the jet had cooled down by the time EIS observed it.
With the advantage of revised the Hinode telemetry mode, we would like to have simultaneous observations from EIS, IRIS and XRT of AR jets. The aim is to study the relationship between the cool and hot component present in the jets and the heating and cooling processes involved during their evolution. Simultaneous observations can give us better constraint in both high and low temperature part in the DEM analysis and also more information about the high density regions.

request to SOT

SOT participation is optional, but two possibilities are the following:

1) If a well-developed sunspot penumbra is included in the IRIS & EIS rasters, run a repeated dynamics mode raster (full resolution, no summing, 2.4 sec integration), with FOV approx. 20 x 60 or 20 x 80 arcseconds, wide enough to cover all of the inner penumbra and most of the outer penumbra on one side of the spot. An East-West ROI offset may be used to place the SP raster as desired on the penumbra. This should run at least 2 hours, telemetry permitting.

2) Run repeated fast maps covering the central portion of the IRIS & EIS rasters, with cadence of 10-20 minutes, similar to HOP 306.

request to XRT

Filters : Al-poly, Be-thin – 512 x 512 – 30 sec cadence (or even higher cadence depending the telemetry)

request to EIS

In the list of existing EIS studies, we found one study – designed by Durgesh Tripathi (Study ID –000361) which covers the high temperature lines suitable for AR jets observation. We are revising the line list for the AR jet studies and will provide a new study in the future. For the time being, we would like the observations to be run using the above mentioned study continuously for at least 6 hours.

EIS study details :
Study name : Active Region Transient Brightening - Lite
Study ID number : 000361
Author : Durgesh Tripathi
Acronym : CAM_AR0_CDS_2AS_LITE
Title : [RA:000346] [Scan: 99(2'') steps] [ss:2''] [wH:4000, nWins:22, LL:000183] [ExpT(Delay) :
10.00(0)]
Duration : 20 min 46 sec
Step Size : 2''
Exposure time : 10.00 sec
Slit : 2 arcsec
Window height : 400 pixels
Raster type : Scanning
No. of lines : 22
Data volume : 119302.95 kBits

other participating instruments

IRIS Request:
Spectrograph :
OBS ID : 3620107266 | Large sparse 96-step raster 95x120 96s C II Si IV Deep x 4
Spatial | 504.91 | 380.99 | 0.5 | 5.3+/-0.1 | 505+/-0 | 10.5+/-0.0 | 10.5+/-0.0
| 0.0+/-0.0 | 0.0+/-
Slit-Jaw Imager :
FOV : 175'' x 175''
SJI window – C II and Si IV
Exposure time : 4 sec
SJI cadence : 10.5 sec

remarks

Dates:
Time window: We would like the observations to be run for at least 6 hours whenever the target is available.

Target(s) of interest:
The study should be run on suitable on-disk active region, pointing at the western side of the leading sunspot region where jets are most likely to be observed.

References :
Del Zanna, G. 2013b, A&A, 558, A73
Mulay, S. et al. 2016a, A&A, 589, 79
Mulay, S. et al. 2016b, arxiv : https://arxiv.org/abs/1609.08472
Paraschiv, A. et al. 2015, A&A, 579, A96