The Department of Space Science and CSPAR will be hosting various Colloquiums throughout each semester. We invite all faculty, staff and students to join us while we learn more about the research going on in the department! Refreshments will be served for the audience members. Check for dates, speakers, and topics below. For further information on the Colloquiums, please contact space_science_colloquium@uah.edu.

Important

In-person Colloquium will be held Fridays at 12:30pm in Cramer Hall (CRH), room 2096 and on dates provided for each speaking engagement. Refreshments are served for the audience at 12:00pm in the 2nd floor lobby. View Campus Map.

Covid-19 may be weakening, but it has not come to an end. Attendees of the colloquium have the option of wearing masks. If you have tested positive for Covid-19 or have been exposed to the virus, please follow the guidelines provided by the Centers for Disease Control and Prevention (CDC).

Parking: Visitors need to sign in at the Cramer Hall (CRH) front desk and have their ID in order to get a parking pass.


Date: 2/2/2024
Speaker: Evdokiya Kostadinova, Assistant Professor, Physics Department, Auburn University
Title: Experimental validation of mechanisms for electron trapping and acceleration in magnetic islands and stochastic fields

It has been shown that up to 50% of the energy released in the Earth’s magnetosphere during solar flares is carried by energetic electrons. Spacecraft data from ESA’s Cluster mission suggests that energetic electrons are trapped in magnetic islands forming in the Earth’s magnetotail during solar flares. Here we present the results from DIII-D frontiers experiments which studied the effect of magnetic islands and field stochasticity on electron transport. The results suggest that: (i) electrons with energy up to 20MeV can be trapped in magnetic islands, (ii) island growth leads to enhanced electron transport, (iii) electrons are de-trapped from islands during island bifurcation, (iv) field stochasticity caused by island overlap leads to enhanced electron transport. We discuss the physics mechanisms possibly leading to each observation and their applications to solar and space physics. 

Powerpoint Slides

 


Date: 2/9/2024
Speaker: Peter Veres, Assistant Professor, UAH
Title: Polarimetry of Gamma-ray Bursts

Gamma-ray bursts (GRBs for short) were discovered by accident during the cold war by satellites looking for signatures of nuclear detonations in the atmosphere.  These brief explosions occur at the farthest reaches of the Universe and involve narrow jets traveling close to the speed of light.  GRBs release roughly the same amount of energy in at most a few minutes as our Sun does during its entire lifetime. According to our current understanding, GRBs mark the death of massive stars (a few times 10 Solar masses) or the merger of two neutron stars.  Basic questions about the physics of GRBs have yet to be answered. These include: 1.) The jet composition: Is the energy in the jet carried by magnetic fields or by baryons? 2.) The structure of the magnetic fields in the emission region: Are they ordered or oriented randomly? 3.) What is the emission mechanism: Is it synchrotron radiation or some modified thermal process?
I will argue that past spectral and temporal observations of GRBs have been maximally exploited for addressing these questions and a fundamentally different approach is needed to achieve significant progress. Sensitive polarization measurements will open up a new dimension for GRBs and will naturally address the above questions.  The LargE Area burst Polarimeter (LEAP) is a proposed mission to the International Space Station, launching in 2027. For the first time, LEAP will make the high-fidelity polarization and spectroscopic measurements of a large number of GRBs.  LEAP will open a new window into the nature of the most energetic phenomena in the universe with gamma-ray polarization.  I will review our current understanding of GRB physics and discuss how polarimetric gamma-ray observations will help us tackle the remaining open questions.

 


Date: 3/1/2024
Speaker: Max Bonamente, Professor, Department of Physics, UAH
Title: Statistical methods for the sciences: Hypothesis testing and systematic errors in count data

Much of astronomy is based on the collection of photon events, oftentimes binned by energy or time into spectra or light curves. The regression of these data with a parametric model is therefore a key aspect of the data analysis for the physical sciences in general, and for astronomy in particular. The presentation focuses on hypothesis testing, i.e. the assessment of the goodness-of-fit of the data with the model, for Poisson-distributed count data. It also presents a novel method of handling the presence of systematic errors, based on the use of an intrinsic model variance that makes the incorporation of systematic errors in the regression and hypothesis testing rather straightforward.

 


Date: 4/5/2024
Speaker: Subramania Athiray Panchapakesan, Assistant Professor, UAH
Title: Plasma Diagnostics of Solar Corona using Wide-Field Imaging Spectroscopy

 


Date: 4/12/2024
Speaker: Dongsheng Wu, Professor, Department of Mathematics, UAH

Title: Space-Time Regularity of the Solution to a Stochastic Heat Equation Driven by a Fractional-Colored Noise

 


Date: 4/19/2024
Speaker: Lingling Zhao, Assistant Professor, UAH
Title: Low-frequency waves in the solar wind

 


 

Fall 2023 colloquium schedule 

Spring 2023 colloquium schedule

 Fall 2022 colloquium schedule