mountain profile Institute for Astronomy University of Hawaii

Research


Latest News: I Graduated!

On October 3rd, 2011 I defended my Ph.D. dissertation entitled: "Exploring Dynamic Events in the Solar Corona". At times it was hard to see the forest for the trees but I am genuinely satisfied with how it came out in the end.

For a thorough documenting of my project from the start to finish I encourage you to take a look at my dissertation, which you can find here.

I am partucularly excited about our latest results from a coupled observation and modeling analysis of an EUV wave observed by the Atmospheric Imaging Assembly onboard the NASA Solar Dynamics Observatory. Please see a recently submitted preprint of our manuscript for more details.


Current Work

"Connecting and Constraining Data-Driven Solar Atmosphere Models Through Observations: Studying EUV Emission in Realistic Flare-CME Events"

This is my main research project for my 3-year NASA Earth and Space Science Fellowship (NESSF08) Award for Heliophysics Research (Advisor: Ilia Roussev). In short the goal is to study Extreme Ultraviolet Emission from the solar atmosphere using a 3-D global simulation tool for the entire corona in context of actual events that we observe. The primary science driver is the study of EUV waves, which are large-scale waves propagating along the solar disk and are related to the impulse from Flare-CME events.


Below are links to related papers and posters as well as some images to give a flavor for what I've been been working on for my dissertation.

Refereed Papers

C. Downs, I. I. Roussev, B. van der Holst, N. Lugaz, and I. V. Sokolov, "Understanding SDO/AIA Observations of the 2010 June 13 EUV Wave Event: Direct Insight From a Global Thermodynamic Magnetohydrodynamic Simulation", 2011, Submitted to ApJ on 12/03/2011 (pdf)


C. Downs, I. I. Roussev, B. van der Holst, N. Lugaz, I. V. Sokolov, and T. I. Gombosi., "Studying Extreme Ultraviolet Wave Transients with a Digital Laboratory: Direct Comparison of Extreme Ultraviolet Wave Observations to Global Magnetohydrodynamic Simulations", 2011, ApJ, 728, 2 (pdf, DOI)


C. Downs, I. I. Roussev, B. van der Holst, N. Lugaz, I. V. Sokolov, and T. I. Gombosi., "Toward a Realistic Thermodynamic Magnetohydrodynamic Model of the Global Solar Corona", 2010, ApJ, 712, 1219 (pdf, DOI)


N. Lugaz, C. Downs, K. Shibata, I. I. Roussev, and A. Asai, "Numerical Investigation of a Coronal Mass Ejection from an Anemone Active Region: Reconnection and Deflection of the 2005 August 22 Eruption", 2011, ApJ, 738, 127 (ADS, DOI)


O. Cohen, G. D. R. Attrill, N. A. Schwadron, N. U. Crooker, M. J. Owens, C. Downs, and T. I. Gombosi., "Numerical Simulation of the May 12, 1997 CME Event - the Role of Magnetic Reconnection", 2010, Journal of Geophysical Research, 115, A10104 (ADS, DOI)


K. Morzinski, O. Azucena, C. Downs, T. Favaloro, J. Park, V. U, "Circuit Design: An Inquiry Lab Activity at Maui Community College", 2010, ASP Conference Series, 436, 295 (ADS, link)


F. Bridges, C. Downs, T. O'Brien, Il-K. Jeong, T. Kimura, "Limitations on the extent of off-center displacements in TbMnO3 from EXAFS measurements", 2007, Physical Review B, 76, 092109 (ADS, DOI)



Poster Presentations

Fall AGU meeting, Dec 2011: "Realistic MHD Modeling of EUV Waves: Insight From a Coupled Observational and Modeling Analysis". (pdf)


SHINE meeting, Jul 2011: "Understanding SDO/AIA Observations of the 2010 June 13 EUV Wave Event: Direct Insight From a Global Thermodynamic MHD Simulation". (pdf)


Fall AGU meeting, Dec 2010: "Interpreting SDO/AIA Observations of EUV waves: A Preliminary Analysis Using Direct Comparison to Global MHD Simulations". (pdf, ADS)


SHINE meeting, Jul 2010: "Studying EUV Wave Transients with a Digital Laboratory: Direct Comparison of EUV wave observations to Global MHD Simulations". (pdf)


Fall AGU meeting, Dec 2009: "Developing a Thermodynamic MHD Model of the Global Solar Corona with the SWMF" (updated/paper results). (pdf, ADS)


SHINE meeting, Aug 2009: "Developing a Thermodynamic MHD Model of the Global Solar Corona with the SWMF" (initial results). (pdf)


SHINE meeting, Jun 2008: "Studying EUV emission in Realistic Flare/CME environments". (pdf)



Talks

CIAS Workshop: Topology of the magnetic field of Solar Prominences and Associated Cavities, Mar 2011: "FORWARD modeling from Global MHD Simulations". (pptx)


Advanced Computational Capabilities for Exploration in Heliophysical Science (ACCEHS) workshop, Aug 2010: "Studying EUV Wave Transients with a Digital Laboratory: Direct Comparison of EUV wave observations to Global MHD Simulations". (pptx)



Selected Images








Past Projects:

2nd 699 Project (2007-2008): Adding a prescription for EUV emission to a global 3-D coronal model used to study the complex conditions of Coronal Mass Ejections (CMEs). (Advisor: Ilia Roussev)

informal paper: Studying EUV Emission in Realistic Flare-CME Events in the Solar Atmosphere.

poster: Summary of project presented as a poster at the 2008 SHINE conference.


1st 699 Project (2007): Using a simple model to investigate how the large fraction of neutral material in magnetic regions of the photosphere can produce dynamic effects via a strong partial pressure gradient. (Advisor: Jeff Kuhn)

informal paper: Neutral and Molecular Hydrogen Dynamics in Magnetic Regions of the Solar Photosphere

poster: Dated, but gives a motivation and shows the work in progress as of the Summer 2007 AAS meeting


My undergraduate Physics thesis at UC Santa Cruz (2006):

paper: Local Structure Studies of Two Novel Materials Using EXAFS (Advisor: Frank (Bud) Bridges)