Radio observations of solar eruptions
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Radio Observations of Solar Eruptions. N. Gopalswamy NASA/GSFC Greenbelt MD USA Solar Physics with the Nobeyama Radioheliograph Nobeyama Symposium Kiyosato Oct 26-29 2004. Thanks to …. Y. Hanaoka M. Shimojo K. Shibasaki H. Nakajima T. Kosugi S. Enome

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Radio Observations of Solar Eruptions

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Radio observations of solar eruptions

Radio Observations of Solar Eruptions

N. Gopalswamy

NASA/GSFC Greenbelt MD USA

Solar Physics with the Nobeyama Radioheliograph

Nobeyama Symposium Kiyosato Oct 26-29 2004

Kiyosato Oct 26-29, 2004


Thanks to

Thanks to …

  • Y. Hanaoka

  • M. Shimojo

  • K. Shibasaki

  • H. Nakajima

  • T. Kosugi

  • S. Enome

  • Nobeyama staff who pleasantly provided all necessary support

Kiyosato, Oct 26-29 2004


Sun in microwaves

Sun in Microwaves

  • Quiet Solar disk at 10,000 K (most pixels are at this temperature): QS

  • Small bright areas on the disk: active regions (AR), post-eruption arcades (AF)

  • Dark areas on the disk: Filaments (F) because Tb ~ 8000K

  • Bright regions outside the disk: Prominences (P) Tb ~8000 K>> optically thin corona (~200 K); Sometimes mounds consisting of AR loops (Tb > 10000K)

  • Dimming (deficit of free-free emission) can be observed in some limb events.

  • Prominences and filaments erupt as part of coronal mass ejections

  • 100s of eruptions documented on the NoRH web site

  • Selected references: Hanaoka et al., 1994; Gopalswamy et al., 1996; 1999; 2003; Hori et al. 2000; 2002; Kundu et al. 2004

P

F

AF

AR

F

QS

τff = 0.2∫f--2T-3/2n2dl >1 for n=1011 cm-3

T=8000 K, f=17 GHz and L >1 km Tb = T

Kiyosato, Oct 26-29 2004


Eruptions

Eruptions

  • Prominence/filament eruptions

  • (Jets) Kundu, Shimojo

  • (Blobs) Hori, Shibasaki

  • (Waves) White, Aurass

  • (Radio bursts) G. Huang

  • Slow Eruptions

  • Fast eruptions

  • CME-PE statistics

  • Implications to polarity reversal & GCR modulation

Kiyosato, Oct 26-29 2004


Prominence eruption

Prominence Eruption

1992 Jul 31 Hanaoka et al.1994

P

CME

SXT/AF

- Post-eruption arcade in microwaves

- Prominence, Post-eruption Arcade

Consistent with Standard Eruption model

(Carmichael (1964), Sturrock (1968), Hirayama (1974),

Kopp and Pneuman(1976) – CSHKP)

- No CME observations, but SXR Dimming Signature

Kiyosato, Oct 26-29 2004


Three part cme

Three-Part CME

Gopalswamy et al, 1996, 1997

P

16 km/s

12 km/s

AF

4 km/s

Jul 10-11, 93

  • - All features of a typical CME in X-rays and

  • Microwaves

  • Kinetic energy (5.1026 ) < thermal energy (6.1028)

  • Low-end CME

  • Helical motion of the prominence followed by

  • radial eruption

  • Recent examples of helical motion by Hori (2000)

Kiyosato, Oct 26-29 2004


Filament eruption and dimming

Filament Eruption and Dimming

Gopalswamy and Hanaoka, 1998

Final: 68 km/s

Accel: 11ms-2

01:20

06:41

AF

Kiyosato, Oct 26-29 2004


Filament is cme core

Filament is CME CORE

Direct comparison with CMEs became possible when SOHO data started pouring in

MLSO He 10830 images

Gopalswamy, 1999

Additional Core

He10830 filament at17:54 UT slowly rises and reaches the limb by 00:03 UT (2/7)

 tracked in microwaves as a prominence

 becomes the CME core in white light

Kiyosato, Oct 26-29 2004

Gopalswamy et al .98 GRL


Post eruption arcade

Post-eruption Arcade

Yohkoh/SXT images showing the formation of a post-eruption arcade, which lasts for a day

SXR Arcade after eruption

larger volume involved than

Indicated by filament

1-AU Magnetic Cloud

Kiyosato, Oct 26-29 2004


A complex filament eruption

A Complex Filament Eruption

LWS CDAW 2002 (Shimojo), Kundu et al. 2004

See also Hanaoka & Shinkawa, 1999 on covering of bright plage by erupted filament

Kiyosato, Oct 26-29 2004


Two cmes

Two CMEs?

Kundu et al. 2004

7.25 Ro/hr

Onset 04:49

Corrected:4:45

650km/s

50km/s

Kiyosato, Oct 26-29 2004


Cme collision a slow cme is deflected by a fast one

CME Collision: A slow CME is Deflected by a Fast one

  • Slow CME (290 km/s) overtaken by a fast CME (660 km/s)

  • The slow CME core deflected to the left from its trajectory

Kiyosato, Oct 26-29 2004


Acceleration likely caused by the impact of fast second cme

Acceleration likely caused by the impact of fast second CME

Kiyosato, Oct 26-29 2004


Microwave observations of cme initiation

Microwave Observations of CME Initiation

A very fast CME: 5 Rs in less than 30 min  > 2000 km/s

Kiyosato, Oct 26-29 2004


An eruption viewed in microwaves

An Eruption viewed in microwaves

Gopalswamy, Shimojo, Shibasaki, 2004

Kiyosato, Oct 26-29 2004


Microwave emission seems to be from the body of the cme

Microwave Emission seems to be from the body of the CME

02:17 – 02:13

02:17 – 02:16

17 GHz

17 GHz

1635 km/s

C2

C3

02:42

C2

02:30

Kiyosato, Oct 26-29 2004


An eruption viewed in microwaves1

An Eruption viewed in microwaves

02:15 UT

HXR 930 km/s

Hudson et al. 2001

Nobeyama HXT

Catalog

Kiyosato, Oct 26-29 2004


Microwave source evolution

Microwave Source Evolution

HXR

Hudson et al 2001

Kiyosato, Oct 26-29 2004


Similar to moving type iv

Similar to Moving type IV?

1600 km/s

2465 km/s

C2

17 GHz

1925 km/s

73.8 MHz

1635 km/s

Gopalswamy & Kundu 1992

- The Microwave Structure is either the CME

itself or a substructure, but not the core.

- Microwave spectrum (17 and 34 GHz) indicates

nonthermal emission

- Similar to moving type IV burst

C3

Kiyosato, Oct 26-29 2004


Cmes prominence eruptions pes statistical studies

CMEs & Prominence Eruptions (PEs) : Statistical Studies

  • Most studies started with CMEs and found PEs to be the most common near-surface activity (Webb et al., 1976; Munro et al. 1979)

  • Reverse studies were rare. Hori et al. studied 50 NoRH PEs (2/1999-5/2000) and found a 92% association. (They required simultaneous availability of SOHO, Nobeyama and Yohkoh data)

  • A comprehensive study using all the PEs (226) detected automatically showed that 72% of all PEs were associated with CMEs (Gopalswamy et al. 2003a; 2004)

Kiyosato, Oct 26-29 2004


Height time plots of all pes

Height-Time Plots of All PEs

Gopalswamy et al. 2003

  • The height-time plots can be broadly classified as radial (R – 82%) and Transverse (T – 18%)

  • R events reached larger height (1.4Rs) compared to T events (1.19Rs)

  • Most R events (83%) were associated with CMEs; most T events (77%) were not.

  • 134/186 (72%) PEs had CMEs; 42 (22%) had no CMEs; 11 (6%) had streamer changes

  • The majority of Streamer change events were T events; the rest were low-height R events

Kiyosato, Oct 26-29 2004


Radio observations of solar eruptions

Properties of Prominence Eruptions (PEs) with and without CMEs:non-CME PEs are slower, have mostly transverse trajectories, and the maximum height reached is rather small

1.20 Ro

Without

CMEs

22 km/s

Without

CMEs

With

CMEs

68 km/s

With

CMEs

1.40 Ro

Kiyosato, Oct 26-29 2004


2001 08 29 event no cme

17 GHz Nobeyama

2001/08/29 Event: no CME

LASCO

LASCO/C2 images show no changes around the

Time of Prominence Eruption

Kiyosato, Oct 26-29 2004


Streamer change

Streamer Change

Most of these streamers

Disrupted within a day.

Kiyosato, Oct 26-29 2004


Temporal relationship of pes and cmes

Temporal Relationship of PEs and CMEs

  • The onset time differences close to zero.

  • CME onset times extrapolated to 1 Rs from extrapolating linear h-t plots

Kiyosato, Oct 26-29 2004


Pe cme spatial relationship

PE-CME Spatial Relationship

Open circles 

PEs during

SOHO downtimes

  • Strong evidence for PE-CME association

  • Previously shown by Hundhausen (1993) for SMM CMEs

During Solar Minima

the global dipolar field

is strong and guides

eruptions

PE

CME

Kiyosato, Oct 26-29 2004


Non radial motion

Non-radial motion

  • Prominence Eruption in the SE direction

  • Corresponding changes in the streamer

  • CME & Core position angle ~ 90 deg

  • Influence of the global field

    Gopalswamy, Hanaoka, Hudson 1999

    Filippov, Gopalswamy, Lozhechkin, 2001

Kiyosato, Oct 26-29 2004


Cmes prominences

CMEs & Prominences

  • High latitude (HL) prominence eruptions and CMEs during CR 1950-1990 (mid ’99 – early ’02)

  • N-S asymmetry (NHL ends in 11/00; SHL ends in 5/02)

  • These CMEs are not associated with sunspot activity

Gelfreikh et al 2002

Kiyosato, Oct 26-29 2004


Radio observations of solar eruptions

N

+++++

PCF

- - - -

+ + + +

E

W

- - - -

+ + + + +

- - - -

Kiyosato, Oct 26-29 2004

S


Cycle 23

Cycle 23

Arrows: Lorenc et al. 2003; Harvey & Recely, 2003; Gopalswamy et al., 2003

  • HL Rate picks up when polar B declines

  • North polar reversal at the time of cessation of NHL CMEs

  • South polar reversal 1.5 yr later, again coinciding with the cessation of SHL CMEs

  • LL CME rate rather flat after a step-like increase

  • Consistent with the time of PCF disappearance

Kiyosato, Oct 26-29 2004


Cycle 21

Cycle 21

  • Solwind coronagraph on board P78-1 (corrected rates published by Cliver et al., 1994)

  • PCF: Webb et al. 1984; Lorenc et al. 2003

  • KPNO mag data

  • CME cessation coincides with the polarity reversal

Kiyosato, Oct 26-29 2004


Cmes and gcr modulation

CMEs and GCR Modulation

Gopalswamy 2004

Gopalswamy 2004

A<0

A>0

A>0

HL

NoRH PE

LL

Lara et al. 2004

Moraal, 1993

Kiyosato, Oct 26-29 2004


Concluding remarks

Concluding Remarks

  • NoRH has contributed profoundly to the study of CMEs by providing info on various aspects: CME initiation/acceleration, Post-eruption arcade, CME relation to global B

  • Clarified CME-PE relationship unambiguously

  • Contributed to the understanding of Polarity reversal and high-latitude Eruptions

  • Prom eruptions have implications to Sun-Earth connection as well as Sun-GCR connection

  • It will be great if NoRH can see a 22-yr cosmic ray modulation cycle

Kiyosato, Oct 26-29 2004


Polarity reversal in photospheric field

Polarity Reversal in Photospheric Field

Kiyosato, Oct 26-29 2004


When are the reversals

When are the reversals?

  • HL streamer peak (Feb 2000) implies presence of HL closed structures.  reversal is not complete

  • HL streamer brightness declines significantly towards the end of 2000 – agrees with CME cessation

Wang, Sheeley & Andrews, 2002

Kiyosato, Oct 26-29 2004


A high latitude cme pcf

A High-latitude CME & PCF

Nobeyama Radio Prominence

LASCO/C2

Kiyosato, Oct 26-29 2004


Emission mechanisms n t b f nt

Emission Mechanisms(n, T, B, Fnt)

  • Thermal Emission

    - Free-free (8000 K to 10 MK)

    - Gyroresonance (Active Regions)

  • Nonthermal

  • Gyrosynchrotron (incoherent)

    - Plasma emission (nonthermal electrons  plasma waves  radio emission at fp, 2fp)

  • Other coherent processes

Kiyosato, Oct 26-29 2004


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