Stephen Brown

 

Astro-WB-SABPhD Student

I am working with Prof. Lyndsay Fletcher on solar flares. We are currently looking at the behaviour of the chromosphere during flares, with a particular focus on the hydrogen Lyman lines.

After using EVE observations to measure Doppler shifts in these lines, we found signatures of both plasma upflows and downflows. We are now using radiative hydrodynamic and radiative transfer codes, RADYN & RH, to produce simulated H Lyman profiles and understand their formation in the solar atmosphere. In 2016 I visited the NASA Goddard Space Flight Centre for 4 months to further this work, and presented our observations at the SDO Living With A Star conference in Vermont.

Publications:

Doppler speeds of the hydrogen Lyman lines in solar flares from EVE – Astronomy & Astrophysics -11/2016 – Stephen Brown, Lyndsay Fletcher & Nicolas Labrosse

Hydrogen Balmer Line Broadening in Solar and Stellar FlaresAstrophysical Journal – 2017 – Adam F Kowalski, Joel C Allred, Han Uitenbroek, Pier-Emmanuel Tremblay, Stephen Brown, Mats Carlsson, Rachel A Osten, John P Wisniewski, Suzanne L Hawley

Radiative hydrodynamic modelling of the hydrogen Lyman lines in the flaring chromosphere [in prep]

Room 604
School of Physics and Astronomy
Kelvin Building
University of Glasgow
G12 8QQ
Scotland

Email: s.brown.6@research.gla.ac.uk

Tel: +44 141 330 2960
Fax: +44 141 330 8600

Peter Levens

PhD Student

I am working with Dr. Nicolas Labrosse and Prof. Lyndsay Fletcher on solar tornado-like prominences – these features appear to be the rotating legs of prominences.

My research has mostly been using UV and EUV observations from the Hinode and IRIS satellites and the ground-based THEMIS telescope in the Canary Islands. In 2014 and 2015 I was part of an international team that coordinated and performed observations with Hinode, IRIS, and THEMIS. I had the opportunity to spend four weeks making observations of prominences at THEMIS as part of that campaign. I also spent four months at the Observatoire de Paris in Meudon, working with Dr. Brigitte Schmieder on analysing IRIS data that we gathered in 2014.

I have also spent some time developing a radiative transfer code that simulates the emission of ionised magnesium (Mg II) lines in prominences. This work has built upon the already-substantial code for modelling hydrogen, helium, and calcium in prominences, provided to me by Dr. Nicolas Labrosse. The aim of this work was to extend previous prominence Mg II models to explain recent IRIS observations.

I am currently at the end of my PhD, writing my thesis.

Publications:

“Comparing UV/EUV line parameters and magnetic field in a quiescent prominence with tornadoes” — P. J. Levens, N. Labrosse, B. Schmieder, A. López Ariste, L.Fletcher. 2017, Astronomy and Astrophysics, (accepted, awaiting publication) [doi] [arXiv]

“Reconstruction of a helical prominence in 3D from IRIS spectra and images” — B. Schmieder, M. Zapiór, A. López Ariste, P. J. Levens, N. Labrosse, R. Gravet. 2017, Astronomy and Astrophysics, (accepted, awaiting publication) [doi] [arXiv]

“Halpha Doppler shifts in a tornado in the solar corona” — B. Schmieder, P. Mein, N. Mein P. J. Levens, N. Labrosse, L. Ofman. 2017, Astronomy and Astrophysics, 597, A109 [doi] [arXiv]

“Magnetic Field in Atypical Prominence Structures: Bubble, Tornado, and Eruption”P. J. Levens, B. Schmieder, A. López Ariste, N. Labrosse, K. Dalmasse, B. Gelly. 2016, The Astrophysical Journal, 826, 164L [doi] [arXiv]

“Structure of Prominence Legs: Plasma and Magnetic Field”P. J. Levens, B. Schmieder, N. Labrosse, A. López Ariste. 2016, The Astrophysical Journal, 818, 31L [doi] [arXiv]

“A solar tornado observed by EIS: Plasma diagnostics”P. J. Levens, N. Labrosse, L.Fletcher, B. Schmieder. 2015, Astronomy and Astrophysics, 582, A27 [doi] [arXiv]

Conference proceedings:

“Prominence and tornado dynamics observed with IRIS and THEMIS” — B. Schmieder, P. J. Levens, N. Labrosse, P. Mein, A. López Ariste, M. Zapiór. 2017, American Astronomical Society, SPD meeting No. 48

“Prominence plasma and magnetic field structure – A coordinated observation with IRIS, Hinode and THEMIS” — B. Schmieder, N. Labrosse, P. J. Levens, A. López Ariste. 2016, 41st COSPAR Scientific Assembly

“Magnetic Field and Plasma Diagnostics from Coordinated Prominence Observations” — B. Schmieder, P. J. Levens, K. Dalmasse, N. Mein, P. Mein, A. López Ariste, N. Labrosse, P. Heinzel. 2016, Astronomical Society of the Pacific, ASP Conference Series, Vol. 504

“Polarimetric measurements in prominences and “tornadoes” observed by THEMIS” — B. Schmieder, A. López Ariste, P. J. Levens, N. Labrosse, K. Dalmasse. 2014, Proceedings of the International Astronomical Union, IAU Symposium No. 305

Contact information:

Room 604
School of Physics and Astronomy
Kelvin Building
University of Glasgow
G12 8QQ
Scotland

Email: p.levens.1@research.gla.ac.uk

Tel: +44 141 330 2960

Paul Wright

 

PhD Student

pjwright_photoI am a third-year Ph.D. student studying the heating of non-flaring/micro-flaring active regions, supervised by Dr Iain Hannah.

My interests range from stellar to solar physics; my main interests lie in the heating of the solar atmosphere, including active regions and loops. I am currently gaining expertise in analysis of data from SDO/AIA, Hinode/XRT, Hinode/EIS, and NuSTAR. For more information see my personal webpage (details below), or my profile on ResearchGate.

Personal homepage
(the contents of which are the responsibility of Paul Wright)

Publications:

[1] Andrew J. Marsh, David M. Smith, Lindsay Glesener, Iain G. Hannah, Brian W. Grefenstette, Amir Caspi, Sam Krucker, Hugh S. Hudson, Kristin K. Madsen, Stephen M. White, Matej Kuhar, Paul J. Wright, Steven E. Boggs, Finn E. Christensen, William W. Craig, Charles J. Hailey, Fiona A. Harrison, Daniel Stern, and William W. Zhang 2017. First NuSTAR Limits on Quiet Sun Hard X-Ray Transient Events, ApJ (in revision)

[2] Juntao Wang, Paulo J. A. Simoes, Natasha L. S. Jeffrey, Lyndsay Fletcher, Paul J. Wright, Iain G. Hannah 2017. Observations of Reconnection Flows in a Flare on The Solar Disk, ApJL, 847, L1

[3] Paul J. Wright, Iain G. Hannah, Brian W. Grefenstette, Lindsay Glesener, Säm Krucker, Hugh S. Hudson, David M. Smith, Andrew J. Marsh, Stephen M. White, and Matej Kuhar 2017.
Microflare Heating of a Solar Active Region Observed with NuSTAR, Hinode/XRT, and SDO/AIA, ApJ, 844, 132

[4] Matej Kuhar, Säm Krucker, Iain G. Hannah, Lindsay Glesener, Pascal Saint-Hilaire, Brian W. Grefenstette, Hugh S. Hudson, Stephen M. White, David M. Smith, Andrew J. Marsh, Paul J. Wright, Steven E. Boggs, Finn E. Christensen, William W. Craig, Charles J. Hailey, Fiona A. Harrison, Daniel Stern, and William W. Zhang 2017. Evidence of Significant Energy Input in the Late Phase of a Solar Flare from NuSTAR X-ray Observations, ApJ, 835, 6

A CV (pdf) can be found here

Room 614
School of Physics and Astronomy
Kelvin Building
University of Glasgow
G12 8QQ
Scotland

Paul.Wright@glasgow.ac.uk

Tel: +44 141 330 8855 x0855
Fax: +44 141 330 8600

 

Aurora over Glasgow

On the 7th October 2015, bright aurora/northern lights were visible over Glasgow due to fast solar wind from a coronal hole on the Sun. A&A group member Dr Iain Hannah was able to photograph this aurora (shown below) and a time lapse of it is available here.

SR_DSC01242

First NuSTAR image of the Sun

NuSTAR Sun

Above is the first image of the Sun taken by NASA’s X-ray telescope NuSTAR. The blue and green are NuSTAR X-rays in 2-3 keV and 3-5 keV, overlaid onto EUV emission from SDO/AIA (red). This image was recently released and has featured on many news sites (BBC, Time, National Geographic, etc) and made it to the Astronomy picture of the day. A&A’s Dr. Iain Hannah and Dr. Hugh Hudson are part of the NuSTAR solar team that is using this X-ray telescope, that normally looks at distant blackholes, to probe faint signatures of heating and particle acceleration in the solar atmosphere.