# Presentation: 860248

## Chromospheric Anemone Jets Outside of Sunspots in Active Regions

- K. Shibata
- Kwasan and Hida Obs., Kyoto Universityand
- T. Nakamura, N. Nishizuka,
- T. Matsumoto, K. Otsuji, S. Nagata,
-  Kyoto/Kwasan-Hida team, Hinode/SOT team

- 2007 Aug 22,  ” First Results from Hinode”, Dublin, Ireland

## Yohkoh/SXT discovered X-ray jet (Shibata et al. 1992,     Strong et al. 1992,  Shimojo et al. 1996)

- Introduction

- Anemone (Shibata et al. 1994)

## 2D-MHD simulation of jetsbased on reconnection model(Yokoyama and Shibata 1995, 1996) 

## Polar X-ray jets observed by Hinode/XRT

- Origin of high speed solar wind ?  Source of Alfven waves ?  (Cirtain et al. 2007)

- (Shimizu et al. 2007)

## Prediction of ubiquitous jets in the solar atmosphere (Shibata 1998)

## Question

- Has Hinode really observed ubiquitous cool jets ?

## Answer: Yes !Discovery of many jets in Ca II  H  images

-  Dec 17  20:00-21:00 UT CaII H broad band filter images taken with Hinode/SOT

## No.1 2006 Dec 17 20:00-21:00

## No. 22006 Dec 17 20:00-21:00

## No. 32006 Dec 17 20:00-21:00

## Various Ca II H jets

- Yohkoh
- Anemone
- X-ray jet

## Relation to magnetic field

- CaII H               FG Stokes V

## What is the velocity of Ca jet ?

- Time-distance diagram

- 2007 Jan 14 jet

- typical velocity =
-     10 ~ 20 km/s

- Jet Velocity = 10~20 km/s
-  ~ Alfven velocity in the low chromospehre or
-      photosphere
- => consistent with reconnection model

## Velocity :  5 – 20 km/s

- Nakamura et al. (2007)

## Length : 500 - 2000 km

- Nakamura et al. (2007)

## Width : 100 – 300 km

- Nakamura et al. (2007)

## Life time : 100 - 200 sec

- Nakamura et al. (2007)

## Relation between velocity and  length of the jet

- Length (10 km)

- Velocity
- (km)

- Nakamura et al. (2007)

## Meaning of velocity of jet

- If the jet is ejected at 10 km/s with ballistic motion, maximum height of the jet would be

- So the jet cannot reach height greater than 200km !

- This suggests that the jet may be accelerated
- by slow mode shock (or Alfven wave)
- generated by reconnection

## Shibata(1998)’s prediction

- Shibata, Suematsu et al. (1982) showed that if an explosion occur below middle chromosphere,  the jet is produced by
- slow shock generated by the explosion

## height

- time

- 1D MHD simulation
- Saitoh, Kudoh, Shibata
- (2001) ApJ

- Hinode
- Observation

- density

- Slow shock

- cf) rebound shock
- Model (Sterling)

## Relation between velocity and  length of the jet

- Length (10 km)

- Velocity
- (km)

- Nakamura et al. (2007)

## Relation between velocity and  length of the jet

- Length (10 km)

- Velocity
- (km)

- Velocity-Length relation for slow shock  jet model (Shibata and Suematsu 1982)

- L∝V2 /g ∝ V
- (g ∝  V)
- Hansteen et al. 2006

- Nakamura et al. (2007)

## Conclusion

- Hinode discovered ubiquitous Ca jets (anemone jets) in the solar chromosphere
- Width ~ 100 - 300 km, length ~ 500 - 2000 km, Velocity ~ 5 – 20 km/s, lifetime ~ 100 – 200 sec
- there is evidence of reconnection such as morphology (anemone) and magnetic field distribution,  suggesting ubiquitous reconnection  in the solar atmosphereas conjectured by Parker (1988)
- Chromoshperic anemone jet seems to be accelerated by slow mode shock generated by the reconnection(Shibata et al. 1982, Shibata and Suematsu 1982) .