Solar Flares
Download
1 / 28

Solar Flares - PowerPoint PPT Presentation


  • 150 Views
  • Uploaded on

Solar Flares. Phillip Chamberlin University of Colorado Laboratory for Atmospheric and Space Physics (LASP) [email protected] (303)492-9318. Outline. Solar Atmosphere Flux Tubes Two Ribbon Flare Cartoons Movies Irradiance Measurements of Flares VUV White Light TSI.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Solar Flares' - umed


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Solar Flares

Phillip Chamberlin

University of Colorado

Laboratory for Atmospheric and Space Physics (LASP)

[email protected]

(303)492-9318


Outline
Outline

  • Solar Atmosphere

  • Flux Tubes

  • Two Ribbon Flare

    • Cartoons

    • Movies

  • Irradiance Measurements of Flares

    • VUV

    • White Light

    • TSI

Chamberlin - Solar Flares - REU 2007


Xuv euv and fuv solar spectrum
XUV, EUV, and FUV Solar Spectrum

Transition Region

From Lean (1997)

Chamberlin - Solar Flares - REU 2007


Solar images oct 28 2003
Solar Images - Oct. 28, 2003

Chromosphere

H-Alpha

Corona

Photosphere

Transition Region

(Images courtesy of Big Bear Solar Observatory and SOHO EIT)

Chamberlin - Solar Flares - REU 2007


Flux tubes
Flux Tubes

(Schrijver and Zwaan, 2000)

Chamberlin - Solar Flares - REU 2007


Flux tubes1
Flux Tubes

Initial rotating convection zone with weak vertical B-field lines

B-field lines concentrated in strands between convection cells to form Flux Tubes

Absence of B-field within convection cells due to B-field line reconnection

(Schrijver and Zwaan, 2000)

Chamberlin - Solar Flares - REU 2007


Emerging flux
Emerging Flux

Solar Atmosphere

Active Regions

Balance between hydrostatic pressure and magnetic pressure causes the flux tubes to be less dense due to their stronger magnetic pressure buoyant flux tubes

Convection Zone

(Schrijver and Zwaan, 2000)

Chamberlin - Solar Flares - REU 2007


Emerging flux title 2004
Emerging Flux (Title, 2004)

Chamberlin - Solar Flares - REU 2007


Phases of solar flares
Phases of Solar Flares

(Adapted from Schrijver and Zwaan, 2000)

Microwave Radio (~3000 MHz)

Radio (100-500 MHz)

H-alpha (656.2 nm)

Broadband EUV (1 - 103 nm)

Soft X-rays (< 10 keV)

X-rays (10-30 keV)

Main Phase

Hard X-rays (> 30 keV)

Impulsive Phase

Note: Soft X-rays: 0.1-10 nm,

Hard X-rays: 0.001-0.1 nm

Precursor

Chamberlin - Solar Flares - REU 2007


Two ribbon flare
Two-Ribbon Flare

Eruption when some critical limit is reached

Triggered by Emerging Flux?

Continued thermal heating and formation of post-flare loops

“Stretching” of field lines

(Priest, 1981)

Chamberlin - Solar Flares - REU 2007


Two ribbon reconnection
Two-Ribbon Reconnection

Thick-target model produces Bremsstrahlung radiation in the transition region and chromosphere due to their much higher densities - Impulsive Phase!

Reconnection after instability accelerates material down loop. Observed Hard X-ray (and EUV?) enhancements at loop top.

[Ashwanden,

2004]

Energy deposited during the impulsive phase heats the plasma up and rises (chromospheric evaporation) to fill flux tube - Gradual Phase!

No enhanced emissions during the impulsive phase in the corona due to its low density.

Chamberlin - Solar Flares - REU 2007


Two ribbon flare1
Two-Ribbon Flare

Impulsive Phases for Each Loop

Post-Flare Loops

(Somov, 1992)

Chamberlin - Solar Flares - REU 2007


X28 flare nov 4 2003
X28 Flare, Nov 4, 2003

Chamberlin - Solar Flares - REU 2007


Hinode sot observes flare
Hinode SOT Observes Flare

Chamberlin - Solar Flares - REU 2007


Soho uv and sorce xps xuv observations
SOHO (UV) and SORCE XPS (XUV) Observations

Chamberlin - Solar Flares - REU 2007


Phases of solar flares1
Phases of Solar Flares

(Adapted from Schrijver and Zwaan, 2000)

Microwave Radio (~3000 MHz)

Radio (100-500 MHz)

H-alpha (656.2 nm)

Broadband EUV (1 - 103 nm)

Soft X-rays (< 10 keV)

X-rays (10-30 keV)

Main Phase

Hard X-rays (> 30 keV)

Impulsive Phase

Note: Soft X-rays: 0.1-10 nm,

Hard X-rays: 0.001-0.1 nm

Precursor

Chamberlin - Solar Flares - REU 2007


Flare pre flare irradiance ratio
Flare/Pre-Flare Irradiance Ratio

Transition region emissions increased by up to a factor of 10 during the impulsive phase

EUV irradiance increased by a factor of 2 during the gradual phase

Flare Variations were as large or larger than the solar cycle variations for the Oct 28, 2003 flare

Chamberlin - Solar Flares - REU 2007


X ray classification
X-Ray Classification

Due to the large, order-of-magnitude increases in the soft X-rays makes for an ideal and sensitive classifications of the magnitude of flares

Chamberlin - Solar Flares - REU 2007


White light flare
White Light Flare

  • “Carrington Flare” September 1, 1859

    • Carrington (M.N.R.A.S, 20, 13, 1860)

  • One of the largest flares believed to have occurred since then

  • Two-Ribbon flare

Chamberlin - Solar Flares - REU 2007


White light vs uv 170 nm flare
White Light vs UV (170 nm) Flare

White Light

TRACE

170 nm

From Hudson et al., AGU/SPD 2005:

http://sprg.ssl.berkeley.edu:80/~hhudson/presentations/spd_wl.050527/

Chamberlin - Solar Flares - REU 2007


X17 flare observed in tsi

First detection of flare in TSI record (G. Kopp, 2003)

X17 flare observed in TSI

Figures from G. Kopp, arranged by T. Woods

Chamberlin - Solar Flares - REU 2007


Conclusions
Conclusions

  • Multiple images and spectral measurements are key to understanding energetic of flares

  • New measurements (Hinode, EVE, AIA, etc.) will lead to a much greater understanding of these processes

  • Biggest mystery still is the ‘trigger’

  • Another topic to that is not fully understood is the relationship of CMEs and Flares

Chamberlin - Solar Flares - REU 2007


Extra slides
Extra Slides

Chamberlin - Solar Flares - REU 2007


Simple loop flare
Simple Loop Flare

Existing Flux Loop that Brightens

TRANSITION REGION

CORONA

CHROMOSPHERE

PHOTOSPHERE

-Most Common Type

-Are these an actual separate type of flare?

-Only Enhanced Internal Motions

(Priest, 1981)

Chamberlin - Solar Flares - REU 2007


Flares drive waves in the photosphere
Flares drive waves in the photosphere

Chamberlin - Solar Flares - REU 2007


Hinode sot movie 2
Hinode SOT Movie #2

Chamberlin - Solar Flares - REU 2007


Vuv irradiance increases dominate flare variations
VUV Irradiance Increases Dominate Flare Variations

  • VUV irradiance (0.1-200 nm) accounts for only 0.007% of quite Sun Total Solar Irradiance (TSI)

  • VUV irradiance accounts for 30-70% of the increase in the TSI during a flare [Woods et al., 2006]

Chamberlin - Solar Flares - REU 2007


Flares cause sudden atmospheric changes
Flares Cause Sudden Atmospheric Changes

GRACE daytime density (490 km)

  • Increased neutral particle density in low latitude regions on the dayside.

  • Sudden Ionospheric Disturbances (SIDs) lead to Single Frequency Deviations (SFDs).

  • Cause radio communication blackouts

  • Cause increased error in GPS accuracy

Latitude (Deg)

2003 Day of Year

(E. Sutton, 2005)

Sudden increase in the dayside density at low latitude regions due to the X17 solar flare on October 28, 2003

Chamberlin - Solar Flares - REU 2007


ad