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Solar REU Intern Projects By Year

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2023 Projects

Development of a Telescope Design System that Will Allow the User to Quickly Design, Analyze, and Specify Telescope Systems for Space Applications

Project Type: Engineering
Skills/Interest Required: Optics, optical alignment, and hands-on testing
Mentors: Mr. Peter Cheimets & Mr. Ed Hertz
Email: pcheimets@cfa.harvard.edu
 
SAO is developing a package that will allow for quick comparisons between optical designs at all levels of their functionality. The system will allow the user to predict the performance of the optical system in the environment in which it will be used, compare that performance with systems designed with different parameters, and, once having selected the final design, fully specify optical systems. The project will involve learning about elementary optics, programming (likely in Matlab,) and the basics of structural and thermal analysis. This is a challenging project within the class of analysis called Structural/Thermal/OPtical (STOP) Analysis, the end point of which will have large ramifications for how optical instruments are designed.

 

Investigating Bizarre Small-scale Explosions Embedded in the Cool Solar Atmosphere

Project Type: Imaging & spectroscopic analysis
Skills/Interest Required: Interest in applying statistical methods to and interpreting physical properties from imaging and spectroscopic data produced by space telescopes. Introductory knowledge of the IDL programming language is recommended but not required.
Mentors: Dr. Chad Madsen & Dr. Ed DeLuca
Email: cmadsen@cfa.harvard.edu
 
For the past nine years, the Interface Region Imaging Spectrograph (IRIS) has provided astrophysicists a never-before-seen glimpse into the bizarre phenomena of the ultraviolet (UV) Sun. The spacecraft owes its success largely to its unprecedented spatial and temporal resolution, which allows it to simultaneously image and sample spectra from previously unresolved, small-scale, transient phenomena in the solar atmosphere. Among the strangest examples is the UV burst, a phenomenon first described by Peter et al. (2014). UV bursts inhabit magnetically active regions and initially appear as small (< 1 arcsec wide) bright dots with lifetimes on the order of a few minutes; however, spectral data reveals a far more dramatic character. Strong emission lines associated with the hot solar transition region often split into two or three peaks of varying shape and intensity when these bursts occur. These peaks are likely due to energetic bidirectional jets reaching upwards of 200 km s-1, likely arising from a process known as magnetic reconnection. Furthermore, the fact that we see these effects in transition region emission lines such as Si IV 1394 Å suggests that the bursts are composed of plasma with temperatures of at least 80,000 K; however, the presence of strong absorption from cool metals like Fe II and Ni II suggests that these hot explosions are deeply embedded in the coolest layers of the solar atmosphere with plasma temperatures closer to 4,000 K. This means these bursts have the potential to contribute to the dramatic and unexplained heating seen in the solar chromosphere and corona. Finally, these bursts can also hold the key to indirectly measuring the magnetic field strength in the solar chromosphere, a notoriously difficult region to observe directly.
 
The goal of this project is to detect and characterize UV bursts in spectral data from the IRIS spacecraft. In particular, the student will apply an algorithm for detecting UV bursts and then use their sample to diagnose physical properties of chromospheric plasma. Image processing, spectroscopic analysis, data handling, and statistical methods will play key roles in this project, four valuable topics for any aspiring astrophysicist to learn. The student will work closely with two professional scientists on this project, receiving personalized coding and physics instruction when the need arises. 

 

Development of a Balloon-borne Coronagraph

Project Type: Hands-on engineering
Skills/Interest Required: Applicants should have an interest in lab instrumentation, a strong math background, and some experience with programming in any language. Familiarity with optics, mechanical design, hardware programming, or MATLAB is a plus.
Mentors: Dr. Jenna Samra & Ms. Vanessa Márquez
Email: jsamra@cfa.harvard.edu
 
The Sun’s corona is notable for its million-degree temperatures and its violent eruptions, but we don’t understand exactly how coronal heating takes place, and we can’t predict precisely when solar activity will occur. Both of these features are controlled by the corona’s magnetic field which is extremely difficult to measure. At the CfA, we are building a new instrument called CORSAIR to measure the coronal magnetic field with unprecedented sensitivity from a high-altitude balloon. CORSAIR will observe the corona continuously for at least one month from higher than 100,000 feet over Antarctica, making magnetic field measurements that will give us a deeper understanding of the Sun’s outer atmosphere.
 
The REU student will help with the development of CORSAIR.  Possible tasks include designing simple mechanical components, writing software to automate focus mechanisms, and/or defining the optical alignment plan and proving it out with a simple lab prototype.

 

Evaluating Models of the Sun’s Corona for Parker Solar Probe’s Most Recent Solar Encounters

Project Type: Data analysis & numerical simulations.
Skills/Interest Required: Some familiarity with Python or another high-level programming language is needed. No specific solar physics knowledge is required, but you will learn a lot by doing this project.
Mentors: Dr. Sam Badman, Dr. Yeimy Rivera, & the CfA SWEAP team
Email: samuel.badman@cfa.harvard.edu
 
The solar corona is the tenuous outer region of the Sun’s atmosphere that can be seen when a total eclipse occurs. It consists of a million degree Kelvin plasma that is shaped by the Sun’s magnetic field. Because it is so hot (1000x hotter than the surface of the Sun,) this plasma is continually expanding and escaping into the Solar System forming what is called the solar wind. We don’t fully understand (1) what sustains such huge temperatures and (2) how the acceleration of the solar wind happens. One key tool for understanding these big questions are numerical models of the corona. However, we need to be able to judge how accurate these models are in a systematic way. In Badman et al. (2022) we defined several metrics in an attempt to do this.
 
In this project, we will apply these metrics to models of the corona from the most recent encounters of the NASA mission, Parker Solar Probe (PSP), which is currently orbiting closer to the Sun than any prior spacecraft. The goal will be to determine what model parameters best represent the corona and explain data taken by PSP. The student will learn to (1) run and interpret potential field source surface (PFSS) models that reconstruct the coronal magnetic field using open-source software from pfsspy, (2) download, plot, and analyze remote observations of the corona as well as in situ data of the solar wind all from active spacecraft throughout the Solar System, and (3) bring these aspects together to judge how good the models can reproduce coronal and solar wind conditions. This will involve using other Python packages such as sunpy and astropy.

 

A Tale of Two Intense Geomagnetic Storms in Solar Cycle 23

Project Type: Data analysis
Skills/Interest Required: Interest in analyzing space- and ground-based data. The basics of the IDL programming language is recommended but not required.
Mentor: Dr. Nishu Karna & Dr. Tatiana Niembro Hernández
Email: nishu.karna@cfa.harvard.edu
 
One of the fundamental properties of the Sun is its magnetic structure: a combination of closed and open field lines. Coronal holes are regions of open, unipolar magnetic fields where high-speed solar wind particles are accelerated into interplanetary space, thus playing a crucial role in heliophysics as one of the main drivers of geomagnetic activity. Active regions, areas of strong closed magnetic fields, host many eruptive events such as flares, filament/prominence eruptions and coronal mass ejections (CMEs), which may cause geomagnetic storms. Understanding how the interaction between the open- and closed-field regions results in geoeffective CMEs  is a fundamental requirement for predicting the effects of the Sun upon Earth. During the summer, the student will study intense geomagnetic storm events from Solar Cycle 23 and perform the following: (1) construct Kitt Peak Vacuum Telescope synoptic maps of He I 1083 nm, (2) extract and measure the physical parameters of coronal holes, including size and locations, and (3) identify and analyze signatures of CMEs and high-speed streams in in-situ data at 1 AU.

 

Plasma Heating by Counterpropagating Electromagnetic Waves in the Solar Wind

Project Type: Data analysis
Skills/Interest Required: The student will gain experience in scientific computing, such as design and execution of numerical calculations in Python or similar languages, and in the management of large data sets. The project will include knowledge/teaching about the physics of space plasmas (wave-particle dynamics, E&M, etc.) Prior experience or coursework in these subjects is helpful but not required.
Mentors: Dr. Kristoff Paulson, Dr. Mike Stevens, & the CfA SWEAP team
Email: kpaulson@cfa.harvard.edu
 
The solar wind plasma that makes up the constant flow of mass outwards from the Sun is an ionized sea of particles. Due to the extremely low density in interplanetary space, the dominant exchange of energy across particle populations is through wave activity. These wave-particle interactions are one of the proposed drivers of solar wind and coronal plasma heating, two as yet unsolved problem. Plasma waves exist across a very broad range of the frequency spectrum, and can manifest with a variety of characteristics depending on their generation conditions and driving mechanisms. A subset of these waves oscillate at frequencies close to the rate at which the surrounding protons and alpha particles spiral around the local magnetic field. These “ion-scale” waves are able to engage in resonant interactions with solar wind ions, efficiently transferring energy in ways that heat the particle distributions. 
 
Over the last year, the Parker Solar Probe spacecraft has spent a portion of each of its highly elliptical orbits inside of the “sub-Alfvénic” surface surrounding the Sun, producing the first in-situ measurements of the atmosphere of a star . For this project, the student will analyze periods of observed wave activity in and around this region using magnetic and electric field measurements to calculate wave energy propagation. They will build a dataset of events where these waves are able to resonantly interact with the outflowing plasma and evaluate these observations relative to measured plasma properties (such as plasma temperature perpendicular and parallel to the magnetic field.) The student will evaluate the degree to which direct plasma heating by wave activity can be observed and how much this energization contributes to the overall heating of the solar wind.

 

Shockwaves in Space: Can One Satellite Tell Us What's Coming, or Do We Need a Fleet?

Project Type: Data analysis
Skills/Interest Required: No special skills required. The student will perform initial analysis using pre-existing GUI software. Higher-level data analysis may be done in the scientific computing environment of the student's choice.
Mentors: Mr. Lucas Guliano & Dr. Mike Stevens
Email: lucas.guliano@cfa.harvard.edu
 
When solar eruptions or solar wind fronts arrive at the Earth, they often drive enormous shock waves, striking at the Earth's magnetic shield with a sudden and dramatic jolt. These shock waves and the gusts of solar wind that drive them produce terrestrial phenomena that are quite beautiful (the aurora) but occasionally quite dangerous, causing atmospheric disturbances that can compromise GPS satellites or even electrical currents in the ground that can cripple power systems. The Wind spacecraft is one of four "space weather stations" that orbit upstream of the Earth and that might measure these shocks before they arrive. The other three stations can detect the arrival of a shock, but the instruments on Wind make it uniquely capable of measuring a shock's properties. From the Wind measurements, it is possible to estimate the speed and direction of the shock wave, thereby predicting when and from what angle it will strike the Earth.
 
Shock waves of varying degree are measured by Wind and detected by other spacecraft every few weeks during the solar maximum (which is now!) The student will learn to recognize these events in the spacecraft observations, building a data set from the present solar maximum, and will then apply the physics model we use to estimate shock speed, magnitude, and direction. The student will then test that model by comparing their estimates against the times and points of detection provided by (at least) three other near-Earth spacecraft: the Deep Space Climate Observatory, the Solar Heliospheric Observatory, and the Advanced Composition Explorer. In this way, the student will test whether a single weather station like Wind is sufficient for forecasting shocks at the Earth, or whether a multi-spacecraft constellation is required that can sample the shock at four separate points in space and time.

 

Heating During Solar Eruptions Observed at X-ray Wavelengths 

Project Type: Data analysis
Skills/interest Required: An interest in solar eruptions; experience with Python is not required but is a plus.
Mentors: Dr. Kathy Reeves & Dr. Xiaoyan Xie
Email: kreeves@cfa.harvard.edu

Solar eruptions are powerful and dynamic events on the Sun that convert stored magnetic energy into thermal energy that heats flare plasma and provides kinetic energy for coronal mass ejections. Flare plasma can be heated up to 30 million degrees K.  The X-ray Telescope (XRT) onboard the Hinode spacecraft determines temperatures by taking intensity ratios across different filters.  The abundances of first-ionization potential elements in the plasma has an effect on these temperature measurements.

The student will calculate temperatures during eruptions from XRT filter ratios using different abundance assumptions.  We will use the new XRTpy Python package to determine the effects different assumptions have on this measurement.  If time permits, the student will synthesize measurements from the proposed ECCCO mission in order to determine if that mission will be able to discern between different abundance levels during eruptions.

2022 Projects

Development of a Telescope Design System that Will Allow the User to Quickly Design, Analyze and Specify Telescope Systems for Space Applications

Project Type: Engineering
Skills/Interest Required: Optics, optical alignment, and hands-on testing
Mentors: Mr. Peter Cheimets and Mr. Ed Hertz
Email: pcheimets@cfa.harvard.edu
 
SAO is developing a package that will allow an instrument design to quickly compare optical designs at all levels of their functionality. The system will allow the user to predict the performance of the optical system in the environment that it will be used, compare that performance with systems designed with different parameters and, once having selected the final design, fully specify optical system. The project will involve learning about elementary optics, programming (we think in Matlab), and the basics of structural and thermal analysis. This is a challenging project within the class of analysis call Structural/Thermal/OPtical (STOP) Analysis, the end point of which will have large ramifications for how optical instruments are designed.

Investigating Bizarre, Small-scale Explosions Embedded in the Cool Solar Atmosphere

Project Type: Image analysis / Spectroscopic analysis
Skills/Interest Required: Interest in applying statistical methods to and interpreting physical properties from imaging and spectral data produced by space telescopes. Introductory knowledge of the IDL programming language is recommended but not required.
Mentors: Dr. Chad Madsen and Dr. Ed DeLuca
Email: cmadsen@cfa.harvard.edu
 
For the past seven years, the Interface Region Imaging Spectrograph (IRIS) has provided astrophysicists a never-before-seen glimpse into the bizarre phenomena of the ultraviolet (UV) Sun. The spacecraft owes its success largely to its unprecedented spatial and temporal resolution, which allows it to simultaneously image and sample spectra from previously unresolved, small-scale, transient phenomena in the solar atmosphere. Among the strangest examples is the UV burst, a phenomenon first described by Peter et al. (2014). UV bursts inhabit magnetically active regions and initially appear as small (< 1 arcsec wide) bright dots with lifetimes on the order of a few minutes; however, spectral data reveals a far more dramatic character. Strong emission lines associated with the hot solar transition region often split into two or three peaks of varying shape and intensity when these bursts occur. These peaks are likely due to energetic bidirectional jets reaching upwards of 200 km s-1, likely arising from a process known as magnetic reconnection. Furthermore, the fact that we see these effects in transition region emission lines such as Si IV 1394 Å suggests that the bursts are composed of plasma with temperatures of at least 80,000 K; however, the presence of strong absorption from cool metals like Fe II and Ni II suggests that these hot explosions are deeply embedded in the coolest layers of the solar atmosphere with plasma temperatures closer to 4,000 K. This means these bursts have the potential to contribute to the dramatic and unexplained heating seen in solar chromosphere and corona. Finally, these bursts can also hold the key to indirectly measuring the magnetic field strength in the solar chromosphere, a notoriously difficult region to observe directly.
 
The goal of this project is to detect and characterize UV bursts in spectral data from the IRIS spacecraft. In particular, the student will apply an algorithm for detecting UV bursts and then use their sample to diagnose physical properties of chromospheric plasma. Image processing, spectroscopic analysis, data handling, and statistical methods will play key roles in this project, four valuable topics for any aspiring astrophysicist to learn. The student will work closely with two professional scientists on this project, receiving personalized coding and physics instruction when the need arises.

Characterizing Solar Coronal Cavities in Helmet Streamers

Project Type: Data Analysis and Modeling
Skills/Interest Required: Interest in analyzing space- and ground-based imaging data as well as performing numerical modeling. Introductory knowledge of the IDL programming language is recommended, but not required.
Mentor: Dr. Mari Paz Miralles and Dr. Nishu Karna
Email: mmiralles@cfa.harvard.edu and nishu.karna@cfa.harvard.edu
 
Helmet streamers, also known as bipolar streamers, are large-scale quasi-static structures in the solar corona. They separate coronal holes of opposite polarities and present a current sheet between the two open-field domains. In the lower corona, helmet streamers consist of closed magnetic loop-like arcades that connect to the solar surface. In the outer corona, they extend to a radial stalk that connects to the outflowing solar wind. Understanding the physical characteristics of helmet-streamer cavities can provide key information on the processes involved in their evolution. Therefore, studying the morphology, thermodynamic, and magnetic properties of helmet-streamer cavities may shed light on the stability mechanisms of these large structures.
 
During the summer the student will: (1) measure the physical parameters of cavities including size, lifetime, density, temperature, and velocity in the corona by using SDO observations of EUV emission and limb synoptic maps; and (2) produce potential field and non-linear force-free field models of a helmet streamer to interpret observations from SDO/AIA, MLSO/KCOR, and STEREO/EUVI. Data and models already exist or have been started by the mentors. This is a great opportunity to become part of a unique, state-of-the-art study.

Collisional Mixing of Solar Wind Plasma during its Journey from the Sun to the Earth

Project Type: Data analysis & forward modeling
Skills/Interest Required: The student will gain experience in scientific computing, such as design and execution of numerical calculations in Python, IDL, Matlab, or similar languages, and in the physics of space plasmas (fluid dynamics, E&M). Prior experience or coursework in these subjects is helpful but not required.
Mentors: Dr. Kristoff Paulson, Dr. Michael Stevens, & The PSP SWEAP Team
Email: kpaulson@cfa.harvard.edu
 
The Parker Solar Probe mission is visiting the Sun's corona for the first time and making the first-ever direct measurements of the plasma there. This offers unprecedented observations of solar wind plasma in its nascent form. In its journey from the solar corona to the Earth, the streams that make up solar wind plasmas interact, expand, and evolve in a number of different ways. In past years, some researchers have hypothesized that coulomb collisions -- the simple, binary electrostatic interactions between ions -- dictate many of the thermodynamic properties that distinguish different kinds of solar wind. The experiments on board the PSP spacecraft provide an opportunity to test this well-known collisional hypothesis.
 
In this project, the student and their mentor will identify solar wind plasma streams measured both by the Parker Solar Probe and by Earth-orbiting spacecraft such as Wind. These multi-point observations will be compared to evaluate the evolution of plasma distributions as they travel across the inner heliosphere. The student will learn about the physics of plasmas in astrophysical environments and the measurement techniques used to explore them. The student will then learn to use numerical methods to model the collisional transport process and the evolution of the solar wind plasma from one spacecraft to the other. The student and their mentors will use this model to test the collisional hypothesis and, as time permits, evaluate modifications to the model.

Analysis of Protons and Alpha Particles in the Solar Wind with Parker Solar Probe

Project Type: Data analysis and modeling 
Skills/Interest required: The student will gain experience in scientific computing, such as design and execution of numerical calculations in Python, Matlab, or similar languages, and in the physics of space plasmas (fluid dynamics, E&M). Prior experience or coursework in these subjects is helpful but not required.
Mentors:  Dr. Yeimy Rivera, Dr. Tatiana Niembro Hernández, & The PSP SWEAP Team
Email: yeimy.rivera@cfa.harvard.edu
 
The Parker Solar Probe is humanity’s first journey into the atmosphere of the Sun.
 
For this project, the student will analyze observations from the Solar Wind Electrons Alphas and Protons (SWEAP) experiment to characterize streams of charged particles from the Sun, and then use remote observations and state-of-the-art modeling to pinpoint the sources of those streams. The student will then explore how the properties of the solar wind plasma change as it expands into the solar system.
 
The solar wind is largely made up of both hydrogen and helium ions, which are found in different abundances according to the sources of the plasma. The student will identify periods of higher helium abundance observed by the Solar Probe Cup and perform mathematical fits to quantify the physical properties of this population. Through this work, we will characterize the solar wind to gain insight into its solar birthplace and its evolution as it travels away from the Sun. 

Development of a Balloon-borne Coronagraph

Project Type: Hands-on engineering
Skills/Interest Required: Applicants should have an interest in lab instrumentation, a strong math background, and some experience with programming in any language. Familiarity with optics, mechanical design, hardware programming, or MATLAB is a plus.
Mentors: Dr. Jenna Samra and Ms. Vanessa Márquez
Email: jsamra@cfa.harvard.edu
 
The Sun’s corona is notable for its million-degree temperatures and its violent eruptions, but we don’t understand exactly how coronal heating takes place, and we can’t predict precisely when solar activity will occur. Both of these features are controlled by the corona’s magnetic field, which is extremely difficult to measure. At the CfA, we are building a new instrument called CORSAIR to measure the coronal magnetic field with unprecedented sensitivity from a high-altitude balloon. CORSAIR will observe the corona continuously for at least one month from higher than 100,000 feet over Antarctica, making magnetic field measurements that will give us a deeper understanding of the Sun’s outer atmosphere.
 
The REU student will help with the development of CORSAIR.  Possible tasks include designing simple mechanical components, writing software to automate focus mechanisms, and/or defining the optical alignment plan and proving it out with a simple lab prototype.

2019 Projects

Development of a Telescope Design System

Type of Project: Engineering

Skills/Interest Required: Optics, optical alignment, and hands-on testing

Mentors: Peter Cheimets and Ed Hertz

Email: pcheimets_at_cfa.harvard.edu

Background:  SAO is developing a package that will allow an instrument design to quickly compare optical designs at all levels of their functionality. The system will allow the user to predict the performance of the optical system in the environment that it will be used, compare that performance with systems designed with different parameters and, once having selected the final design, fully specify optical system. The project will involve learning about elementary optics, programming (we think in Matlab), and the basics of structural and thermal analysis. This is a challenging project within the class of analysis call Structural/Thermal/OPtical (STOP) Analysis, the end point of which will have large ramifications for how optical instruments are designed.

Observation and Modeling of Solar Coronal Loops

Type of Project: Observations and Simulations

Mentors: Nishu Karna, Mah Asgari-Targhi

Email: nishu.karna_at_cfa.harvard.edu

Background:  The classic picture of the solar coronal loops describes a highly conducting plasma. The plasma evolves due to the random motions of photospheric footpoints. These motions generate Alfven waves that propagate upward in the solar atmosphere. The waves result in turbulence that may heat the solar corona to temperatures ranging from 1-3 MK.

Project:  The aim of this project is to model the energy and heating of solar coronal loops based on Alfven wave turbulence using observations from Solar Dynamic Observatory (SDO) and numerical modeling.

  1. We construct a three-dimensional magnetic model of the solar coronal loops. We select a series of field lines that fit the observations using the Coronal Modeling System (CMS) program.
  2. We simulate Alfven wave turbulence in the selected field lines and compute temperature, density and other model parameters such as Alfven speed and heating rate. We will test if the Alfven wave turbulence can heat the coronal loops and the solar atmosphere to temperatures of 1-3 MK.

What Sets Flares Off?

Type of Project: Data analysis

Mentors: Dr. Vinay Kashyap

Email: vkashyap_at_cfa.harvard.edu

Project:  Flares are impulsive releases of energy from magnetic fields that permeate the corona. They are ubiquitous on the Sun and other stars, and the stronger ones can achieve brightnesses that are a significant fraction of the total stellar radiation output. One of the outstanding questions about flares, though, is what triggers the processes that releases the energy stored in the magnetic fields? We know that flares intensities are distributed as a power-law (dN/dE∝E^-1.8 on the Sun) that holds over several orders of magnitude, from logE≈31 to logE≈26, which suggests that the process that directs the energy release is akin to an avalanche, a so-called Self-Organized Critical process, which is ostensibly scale-free. However, there are limits to how high the flare energies extend on this power-law, and we should start seeing the distribution turn over. In this project, we will explore several things: (1) what is the range of validity over which the power-laws hold, (2) how, if at all, does it change across the solar cycle, and (3) can we identify differences in flare onset behavior for different active regions. We will use existing flare catalogs to carry out the analysis.

Investigating Bizarre, Small-Scale Explosions Embedded in the Cool Solar Atmosphere

Type of Project: Image analysis / Spectroscopic analysis

Skills/Interest Required Interest in applying statistical methods to and interpreting physical properties from imaging and spectral data produced by space telescopes. Introductory knowledge of the IDL programming language is recommended but not required.

Mentors: Chad Madsen and Ed DeLuca

Email: cmadsen_at_cfa.harvard.edu

Background:  For the past six years, the Interface Region Imaging Spectrograph (IRIS) has provided astrophysicists a never-before-seen glimpse into the bizarre phenomena of the ultraviolet (UV) Sun. The spacecraft owes its success largely to its unprecedented spatial and temporal resolution, which allows it to simultaneously image and sample spectra from previously unresolved, small-scale, transient phenomena in the solar atmosphere. Among the strangest examples is the UV burst, a phenomenon first described by Peter et al. (2014). UV bursts inhabit magnetically active regions and initially appear as small (< 1 arcsec wide) bright dots with lifetimes on the order of a few minutes; however, spectral data reveals a far more dramatic character. Strong emission lines associated with the hot solar transition region often split into two or three peaks of varying shape and intensity when these bursts occur. These peaks are likely due to energetic bidirectional jets reaching upwards of 200 km s-1, likely arising from a process known as magnetic reconnection. Furthermore, the fact that we see these effects in transition region emission lines such as Si IV 1394 Å suggests that the bursts are composed of plasma with temperatures of at least 80,000 K; however, the presence of strong absorption from cool metals like Fe II and Ni II suggests that these hot explosions are deeply embedded in the coolest layers of the solar atmosphere with plasma temperatures closer to 4,000 K. This means these bursts have the potential to contribute to the dramatic and unexplained heating seen in solar chromosphere and corona. Finally, these bursts can also hold the key to indirectly measuring the magnetic field strength in the solar chromosphere, a notoriously difficult region to observe directly.

Project:  The goal of this project is to detect and characterize UV bursts in spectral data from the IRIS spacecraft. In particular, the student will apply an algorithm for detecting UV bursts and then use their sample to diagnose physical properties of chromospheric plasma. Image processing, spectroscopic analysis, data handling, and statistical methods will play key roles in this project, four valuable topics for any aspiring astrophysicist to learn. The student will work closely with two professional scientists on this project, receiving personalized coding and physics instruction when the need arises.

Characterizing the Readout Rates of New Soft X-Ray Detectors for Solar Physics

Type of Project: Instrumentation and Data Analysis

Skills/Interest Required Students that are interested in astrophysics, solar physics, instrumentation, and engineering (mechanical, electrical, and optical engineering). Basic understanding of electro- magnetic phenomena, electronics, thermal properties of materials, vacuum chambers, X-ray light sources, soft X-ray detectors, statistics, data reduction methods and analysis techniques will be developed during the project. Students with interest in learning or improving their computer programing skills and strong interest in lab work is required. Students will learn IDL/Python during the project.

Mentors: Dr. Christopher S. Moore

Email: christopher[dot]s[dot]moore_at_cfa.harvard.edu

Project:  The outer atmosphere of the Sun called the corona, is much hotter than the 5,700 K suface (called the photosphere). Large magnetic fields in the corona, called active regions, are the locations where the majority of moderate and large flares originate. Flares heat the local plasma to temperatures over 10 MK which increases on timescales of seconds. This hot plasma emits copious soft X-ray (sxr) and extreme ultraviolet (EUV) emission. The rapid dynamics and high contrast of sxr and EUV solar coronal emission cause current CCD imager pixels to saturate and the electronic charge subsequently ‘blooms’ into adjacent pixels, destroying scientific information. New fast readout detectors can mitigate this issue.

In this project the student will characterize the readout rates of silicon based soft X-ray detectors that could be incorporated into future solar physics space missions. The student will gain laboratory experience with vacuum systems, X-ray sources, X-ray detectors, electronics, mechanical structures, cooling systems, software programing, and solar physics.

Interaction Between Coronal Mass Ejections

Type of Project: Data analysis

Skills/Interest Required The student will gain experience in scientific computing by executing numerical calculations using Fortran, and IDL and in the physics of space plasmas (fluid dynamics and E&M). Prior experience or coursework in these subjects is helpful but not required.

Mentors: Dr. Tatiana Niembro, Dr. Kristoff Paulson and, Dr. Michael Stevens

Email: tniembro_at_cfa.harvard.edu

Background:  Coronal Mass Ejections (CMEs) are powerful solar eruptions that release huge amount of mass into the Interplanetary Medium. Their masses can be as large as 1015–1016 g moving outwards at speeds ranging from a few hundreds to thousands of kilometers per second. Their dynamics are determined by their interactions with the ambient solar wind and other large-scale structures such as corotating interaction regions or other CMEs causing the formation of complex structures.

On March 13th, 1989, several extreme CMEs were expelled out from the Sun and travelled towards the Earth. Their interaction with the solar wind and among them, their evolution and their arrival caused electrical disruptions, the sighting of auroras (northern lights) at lower latitudes reaching Florida and Cuba, and the well known Quebec Blackout, in which the city suffered a twelve hour electrical power blackout. Across the United States, over 200 power grid problems erupted within minutes of the start, but did not end on blackouts. Some satellites lost control. The total damage cost billions of dollars.

On July 23th, 2012 occurred a very similar event, with several CMEs involved, including the fastest CME on record (reaching 3000 km/s) but they were not directed to the Earth but to the STEREO-A spacecraft. From its study it has been predicted that if this particular event had reached the Earth, ‘we would still be picking up the pieces’ and it would have represented a cost more than twenty times the losses of Hurricane Katrina.

These particular events are dramatic examples of how solar storms can affect us. Although they are very rare. Nevertheless, based on the rate of CME production, one can assume that there may be from 2 to 20 CMEs in the 4? sr between the Sun and the Earth, enabling the CME–CME interaction to occur usually, more frequently during the maximum of the solar cycle. The more we can learn about these phenomena (Sun's space weather), the better we can prepare for the next storm when it arrives. Being their understanding, characterization and prediction important tasks for space weather forecasting.

The physics of these phenomena is not yet well understood, and hence, it is still one of the goals of space research. It also gives an excellent scenario to study collisionless plasma physics and the opportunity to study the propagation and evolution of the solar wind.

Project:  We will use data from the Wind spacecraft to identify the arrival of complex structures formed after the interaction between multiple coronal mass ejections. Then, we will look for the CME counterparts with remote sensing observations. After characterizing the solar wind and CME conditions of the flow (speed and mass loss rate) we will simulate these events to corroborate their arrival to Earth and to study their evolution and propagation into the interplanetary medium. We will create a catalog of complex structures, in which we will characterize their origin and arrival to the Earth.

Parker Solar Probe Plasma Wave Interactions

Type of Project: Data analysis

Skills/Interest Required The student will gain experience in scientific computing, such as design and execution of numerical calculations in Python, IDL, Matlab, or similar, and in the physics of space plasmas (fluid dynamics, E&M). Prior experience or coursework in these subjects is helpful but not required.

Mentors: Dr. Kristoff Paulson, Dr. Tatiana Niembro, Dr. Michael Stevens, and Dr. Anthony Case

Email: kpaulson_at_cfa.harvard.edu

Background:  The Parker Solar Probe is humankind's first journey into the atmosphere of the Sun. The outer reaches of this atmosphere, the solar corona, is significantly hotter than the solar surface. One mechanism for this energization is through interactions between waves and particles in the solar wind plasma. The solar wind is a supersonic and very rarefied medium, so the most common way to transfer energy between particle populations is through wave interactions. These waves range from the alfvenic scale at low frequencies which oscillate the plasma structures themselves, all the way through the electron scale at higher frequencies. These different wave modes will have different effects on resonant plasma populations, often preferentially heating particles in certain directions relative to the orientation of the background magnetic field.

Project:  For this project, a student will analyze observations from the Solar Wind Electrons Alphas and Protons (SWEAP) and the Fields experiments to examine periods of wave activity in the magnetic and electric fields and their effects on the thermal plasma population. The student will identify periods of particle heating and active transfer of wave energy to particle populations. As time permits, the student will also examine the effects of observed wave populations occurring at the boundaries of the newly discovered solar wind “switchbacks”.

Alignment and Calibration of an Airborne Eclipse Instrument

Type of Project: Engineering

Skills/Interest Required: Optics, optical alignment, and hands-on testing

Mentors: Jenna Samra And Peter Cheimets

Email:jsamra_at_cfa.harvard.edu

Background: The COronal Spectrographic Imager in the EUV (COSIE) mission is motivated by two objectives: (1) to understand the dynamic physical processes that change closed field to open field and the reverse in the solar corona; (2) to understand the physical processes that control the early evolution of coronal mass ejections in the low corona. COSIE is a combination of the most sensitive EUV imager ever flown and a novel EUV objective grating spectrograph with a field of view extending out to 3 solar radii.

Project:  The sun’s corona is notable for its million-degree temperatures and its violent eruptions, but we don’t understand exactly how coronal heating takes place, and we can’t predict precisely when solar activity will occur. Both of these features are controlled by the corona’s magnetic field, which is extremely difficult to measure. At the CfA, we recently took a step toward making this measurement with the 2017 and 2019 eclipse flights of the airborne infrared spectrometer (AIR-Spec). By observing infrared light emitted by the corona, AIR-Spec measures the corona’s temperature and density and paves the way for a future instrument that will measure its magnetic field. To view an eclipse, the instrument and its operators fly in the National Science Foundation’s Gulfstream V aircraft at an altitude of over 43,000 feet, above the clouds and most of the infrared-absorbing gas in earth’s atmosphere.

We are in the process of building an Airborne Stabilized Platform for InfraRed Experiments (ASPIRE), which will feed AIR-Spec during the December 14, 2020 solar eclipse over South America. This effort includes the development of a new image stabilization system, a larger-aperture telescope, and a new 1430 nm narrowband camera to image an emission line of ionized silicon. The ASPIRE stabilized feed and new 13 cm diameter telescope will improve the AIR-Spec sensitivity, and the narrowband imager will provide a 2D picture of the 1430 nm corona for the first time.

During the summer of 2020, ASPIRE will undergo alignment, wavelength and radiometric calibrations, and lab testing. The REU student will participate in this effort after learning how to operate alignment tools such as a theodolite, interferometer, and broadband collimator. Additional responsibilities will include setting up calibrations, automating the data acquisition process, and analyzing data to produce calibration tables. MATLAB will be used for automation and data analysis. The student should have an interest in instrumentation and some experience with data analysis in any programming language. Familiarity with optics or MATLAB is a plus.