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Nicole Marie Lloyd-Ronning

Nicole Lloyd-Ronning

Phone (505) 665-5421


My expertise is in high energy astrophysics, with a focus on gamma-ray bursts.  Some of my work has been devoted to using gamma-ray bursts as cosmological tools, but the majority involves understanding their intrinsic properties - their emission mechanisms, particle acceleration processes, and the nature of their inner engine. 

 I am also heavily involved in public scientific outreach.  I am a member of the Bradbury Science Ambassadors program, regularly visit elementary schools throughout northern New Mexico to do hands-on physics experiments with students, run a UNM-LA Community Education class and McCurdy high school class on modern astrophysics, and am helping develop the curriculum for a new astronomy class at Los Alamos Middle School.


B.A. in Physics, Cornell University, 1996

Ph.D. in Physics, Stanford University, 2001


LANL Positions

Affiliate, Blewett Fellow; Aug. 2015 - present

Director’s Postdoctoral Fellow, Jan. 2004 - Jan. 2005


Professional Societies

American Physical Society

American Astronomical Society



M. Hildred Blewett Fellowship, American Physical Society, 2015

National Research Council Award (declined), 2001

McMicking Fellowship for Excellence in Graduate Physics, Stanford, 2000



Selected Publications:

Lloyd-Ronning, Nicole M.; Fryer, Christopher L.; On the Lack of Radio Afterglow from Some Gamma-Ray Bursts: Insight Into their Progenitors?; 2016, accepted to MNRAS

Lloyd-Ronning, Nicole M.; Dolence, Joshua C.; Fryer, Christopher L;  A MAD Model for Gamma-ray Burst Variability; 2016, MNRAS, 461, 1045

Lloyd-Ronning, Nicole M.; Fryer, Christopher L.; Particle Acceleration in Relativistic Electron-Ion Outlfows; 2016, arXiv1603.04190

Guo, Fan; Li, Xiaocan; Li, Hui; Daughton, William; Zhang, Bing; Lloyd-Ronning, Nicole; Liu, Yi-Hsin; Zhang, Haocheng; Deng, Wei; Efficient Production of High-energy Nonthermal Particles during Magnetic Reconnection in a Magnetically Dominated Ion–Electron Plasma; 2016, ApJ, 818, L9

Mesler, R. A.; Whalen, Daniel J.; Smidt, Joseph; Fryer, Chris L.; Lloyd-Ronning, N. M.; Pihlström, Y. M.; The First Gamma-Ray Bursts in the Universe; 2014 ApJ, 787, 91

Mesler, Robert A.; Whalen, Daniel J.; Lloyd-Ronning, Nicole M.; Fryer, Chris L.; Pihlström, Ylva M.; Gamma-Ray Bursts in Circumstellar Shells: A Possible Explanation for Flares; 2012, ApJ, 757, 117

 Lloyd-Ronning, Nicole M.; Zhang, Bing; On the Kinetic Energy and Radiative Efficiency of Gamma-Ray Bursts; 2004, ApJ, 613, 477

Gehrels, N.; Chincarini, G.; Giommi, P.; Mason, K. O.; Nousek, J. A.; Wells, A. A.; White, N. E.; Barthelmy, S. D.; Burrows, D. N.; Cominsky, L. R.; and 61 coauthors; The Swift Gamma-Ray Burst Mission; 2004, ApJ, 611, 1005

Zhang, Bing; Dai, Xinyu; Lloyd-Ronning, Nicole M.; Mészáros, Peter; Quasi-universal Gaussian Jets: A Unified Picture for Gamma-Ray Bursts and X-Ray Flashes; 2004, ApJ, 601, L119

Lloyd-Ronning, Nicole M.; Dai, Xinyu; Zhang, Bing; On the Structure of Quasi-universal Jets for Gamma-Ray Bursts; 2004, ApJ, 601, 371

Lloyd-Ronning, Nicole M.; Ramirez-Ruiz, Enrico; On the Spectral Energy Dependence of Gamma-Ray Burst Variability; 2002, ApJ, 576, 101

Lloyd-Ronning, Nicole M.; Fryer, Chris L.; Ramirez-Ruiz, Enrico; Cosmological Aspects of Gamma-Ray Bursts: Luminosity Evolution and an Estimate of the Star Formation Rate at High Redshifts; 2002, ApJ, 574, 554

Ramirez-Ruiz, Enrico; Lloyd-Ronning, Nicole M.; Beam models for gamma-ray bursts sources: outflow structure, kinematics and emission mechanisms; 2002, New Astronomy, 7, 197

Lloyd-Ronning, Nicole M.; Petrosian, Vahé; Interpreting the Behavior of Time-resolved Gamma-Ray Burst Spectra; 2002, ApJ, 565, 182

Lloyd, Nicole M.; Petrosian, Vahé; Mallozzi, Robert S.; Cosmological versus Intrinsic: The Correlation between Intensity and the Peak of the νFν Spectrum of Gamma-Ray Bursts; 2000, ApJ, 534, 227

Lloyd, Nicole M.; Petrosian, Vahé; Synchrotron Radiation as the Source of Gamma-Ray Burst Spectra; 2000, ApJ, 543, 722

Lloyd, Nicole M.; Petrosian, Vahé; Distribution of Spectral Characteristics and the Cosmological Evolution of Gamma-Ray Bursts; 1999, ApJ, 511, 550