After graduating from the University of Surrey, England, with an MPhys degree in Physics with Satellite Technology, Richard Longland moved to the U.S. to pursue a PhD in Nuclear Astrophysics at the University of North Carolina at Chapel Hill in 2004. His thesis work (under the direction of Prof. Christian Iliadis) concentrated on characterising neutron producing reactions in massive stars and Asymptotic Giant Branch (AGB) stars. He also developed Monte Carlo methods for calculating the uncertainties on nuclear reaction rates in stars, which continues to be a key factor in his research today.
In 2010, Richard moved to Barcelona, Spain, to work with Jordi José at the Universitat Politècnica de Catalunya and broaden his experience in nuclear astrophysics. While there, he developed parallel processing nucleosynthesis models to investigate Monte Carlo sensitivity studies in AGB stars, novae, X-ray bursts, and low-mass white dwarf mergers. Using these methods, he was able to perform detailed nucleosynthesis studies to investigate the origin of R Corona Borealis stars.
Richard's over-arching research goal is to understand the origin of the elements and how stars burn their fuel. Almost all of the elements heavier than helium in the solar system were made in stars. The rate of this synthesis by nuclear reactions also governs energy production, and thus the physical structure of stellar environments. To better understand these reactions and how stars burn their fuel, his research group focuses on precisely determining their cross sections in the laboratory. A combination of direct and indirect techniques are used to characterise the nuclear properties of the reactions and their products at the Triangle Universities Nuclear Laboratory (TUNL). In particular, his group uses the only functioning high resolution particle spectrometer dedicated to nuclear astrophysics experiments in North America. This spectrometer allows them to perform charge-exchange and particle transfer measurements, thus providing astrophysicists with critical information where more traditional direct cross section measurements are not feasible. By collaborating with stellar modellers and astronomers, these measurements are used to help improve our understanding of stars and how the elements were made.
The Focal plane Detector Package on the TUNL Split-pole Spectrograph.
Marshall, C.; Setoodehnia, K.; Kowal K.; Portillo, F.; Champagne, A. E.; Hale, S.; Dummer, A.; Longland, R.
IEEE Trans. Instr. Meth., Volume PP, Issue 99, (2018), p.1-14, doi:10.1109/TIM.2018.2847938
Correlated uncertainties in Monte Carlo reaction rate calculations.
Astronomy & Astrophysics, Volume 604, (2017), id.A34, 9 pp., doi:10.1051/0004-6361/201730911
Characterization of a 10 B-doped liquid scintillator as a capture-gated neutron spectrometer.
S. Hunt, C. Iliadis, R. Longland
Nucl. Instr. Meth. Phys. Res. A, 811, (2016), pp. 108-114, doi:10.1016/j.nima.2015.12.001
Statistical methods for thermonuclear reaction rates and nucleosynthesis simulations.
C. Iliadis, R. Longland, A. Coc, F. X. Timmes, and A. E. Champagne
J. Phys. G, 42, (2015), 034007, doi:10.1088/0954-3899/42/3/034007
Thermonuclear reaction rate of 18Ne(a,p)21Na from Monte Carlo calculations.
P. Mohr, R. Longland, and C. Iliadis
Phys. Rev. C, 90, (2014), 065806, doi:10.1103/PhysRevC.90.065806
Performance improvements for nuclear reaction network integration.
R. Longland, D. Martin, and J. José
Astron. Astrophys., 563, (2014), A67., doi:10.1051/0004-6361/201321958
Is γ-ray emission from novae affected by interference effects in the 18F(p,a)15O reaction?
A. M. Laird, A. Parikh, A. S. J. Murphy, K. Wimmer, A. A. Chen, C. M. Deibel, T. Faestermann, S. P. Fox, B. R. Fulton, R. Hertenberger, D. Irvine, J. José, R. Longland, D. J. Mountford, B. Sambrook, D. Seiler, and H.-F. Wirth,
Phys. Rev. Lett., 110, (2013), 032502, doi:10.1103/PhysRevLett.110.032502
Lithium production in the merging of white dwarf stars.
R. Longland, P. Lorén-Aguilar, J. José, E. García-Berro, and L. G. Althaus
Astron. Astrophys., 542, (2012), A117., doi:10.1051/0004-6361/201219289
Charged-particle thermonuclear reaction rates: I. Monte Carlo method and statistical distributions.
R. Longland, C. Iliadis, A. E. Champagne, J. R. Newton, C. Ugalde, A. Coc, and R. Fitzgerald
Nucl. Phys. A, 841, (2010), 1–30., doi:10.1016/j.nuclphysa.2010.04.008
Resonance strength in 22Ne(p,γ)23Na from depth profiling in aluminum.
R. Longland, C. Iliadis, J. M. Cesaratto, A. E. Champagne, S. Daigle, J. R. Newton, and R. Fitzgerald
Phys. Rev. C, 81, (2010), 055804, doi:10.1103/PhysRevC.81.055804
Photoexcitation of astrophysically important states in 26Mg.
R. Longland, C. Iliadis, G. Rusev, A. P. Tonchev, R. J. deBoer, J. Görres, and M. Wiescher
Phys. Rev. C, 80, (2009), 055803, doi:10.1103/PhysRevC.82.025802
Performance Improvements for Nuclear Reaction Network Integration.
R. Longland, D. Martin, and J. Jose
Astron. Astrophys., 563, (2014), A67, doi:10.1051/0004-6361/201321958
Is Γ-ray emission from novae affected by interference effects in the18F(p,α)15O reaction?
A. M. Laird, A. Parikh, A. S. J. Murphy, K. Wimmer, A. A. Chen, C. M. Deibel, T. Faestermann, S. P.Fox, B. R. Fulton, R. Hertenberger, D. Irvine, J. José, R. Longland, D. J. Mountford, B. Sambrook, D. Seiler, and H.-F. Wirth
Phys. Rev. Lett. 110, (2013), 032502, doi:10.1103/PhysRevLett.110.032502
Recommendations for Monte Carlo nucleosynthesis sampling.
Astron. Atrophys., 548, (2012), A30, doi:10.1051/0004-6361/201220386