On coronal streamer changes

On coronal streamer changes

N. Goplasmwamy, M. Shimojo, W. Lu, S. Yashiro, K. Shibasaki, R.A. Howard

Advances In Space Research2004, 33, 676-680

2004年 6月 14日　太陽雑誌会　速報　（森本）　　　　　　　　　　　プロミネンス爆発ゼミ

Abstract

Coronal streamer represents one of the pre-eruption configuration of CMEs. … Characteristics of the streamer-related events.

Motivation :

Streamer-related events are closer to those of prominence eruptions with transverse trajectories.

Main result :

NoRH & SOHO observations on streamer changes with prominence eruptions.

Illustrative examplesstreamer-related VS. general prominence events.

How ?

Introduction

Streamer events : Streamer activities (which show rise motions) with microwave prominence activations or eruptions.

These events do not include CMEs.

Illustrative examples11 events.

Date P-angle Speed Max. Height

SubsequentCME (Time)

34.3 km/s

-12.8 km/s

1.32 Rs

1.09 Rs

NoRH daily mpeg : 1996-2001Overlapped with SOHO LASCO Lacked white-light CMEsStreamer changes were found

226 prominence eruptions186 5211

2000 Jan 18

NoRH (17/23:11 – 18/06:11 UT)

SOHO LASCO18th all day

2000 Jan 18 NoRH

1. Mainly transversal motion (radial speed = 5.2 km/s)

2000 Jan 18 Pic du Midi

2. H prominence eruption

2000 Jan 18 LASCO

1. Slow Swelling during NoRH Observation (11 hours)

2. Eruption as a CME(CME speed = 143 km/s within C2 FOV)

The streamer changes (corresponding to prominence activation or small scale eruption) is slow swelling.

1998 Jun 01

NoRH (31/22:46 – 01/06:36 UT)

SOHO LASCO(01th all day)

1998 Jun 01 NoRH & LASCO

Slow rise (~ 8km/s) Continuous slow swelling from 01th 01:30 UTCME (onset = 02th 08:08 UT)

1998 Jan 01 EIT

Northern part showed a “failed eruption” (05:00 – 06:56 UT).In emission = heated?

The whole NoRH prominence is seen in absorption

199 Jan 01 EIT & NoRH

Overlay of the 17GHz contours on an EIT difference image.

EIT ejecta (denoted by the arrow) reached as high as the leading edge of the microwave prominence.

Summary

Transverse events : transversal motion is dominant.Radial event : radial motion is dominant

Transversal motion (prominence activation) is the dominant for the majority of streamer-related events.