
Department of
Physics
Professor
Calvin W. Johnson Web
pages 

The Eightfold group as of October 2018: Changfeng, Ryan, Raul, Sasha, Jordan, Oliver, Ken, Stephanie. Fall 2022 members: Ryan, Sasha, Jordan, Oliver, Stephanie, Mandy, Austin, Dustin, Heng, Antonio, Edgar, Vladimir, and Eric Facts about COVID19 Important for students! All communication for classes by email will be by your SDSUid Advice for students Some amusing quotes about research The BIGSTICK shellmodel code About me: "Seven things about...." from SDSU News Center Science fiction and the human condition The TeacherScholar Model: Winner of the Thomas B. Day Award for Excellence in Physics NewsSept 22, 2022: New preprint, "dmscatter: a fast program for WIMPnucleus scattering," O. Gorton, C. W. Johnson, C.F. Jiao, J. Nikoleyczik, arXiv:2209.09187
Sept 2, 2022: A new YouTube is up interviewing me about being awarded the inaugural Thomas B. Day Award for Excellent in Physics
Aug 24, 2022: Recent preprints:
“New
insights into backbending in the symmetryadapted
framework,” N. D. Heller, G. H. Sargsyan, K. D. Launey,
C. W. Johnson, T. Dytrych, J. P. Draayer,
arXiv:2205.06943
“Nucleonpair truncation of the shell model for mediumheavy nuclei,” Y. X. Yu, Y. Lu, G.J. Fu, C. W. Johnson, Z. Z. Ren, arXiv: 2208.02079 “An alternative approach to quantum imaginarytime evolution,” P. Jouzdani, C. W. Johnson, E. R. Mucciolo, and I. Stectu, arXiv:2208.10535
Jun 24, 2022: Papers published: “Collective neutrino oscillations with tensor networks using a timedependent variational principle,” M. J. Cervia, P. Siwach, A. V. Patwardhan, A. B. Balantekin, S. N. Coppersmith, C. W. Johnson, Phys. Rev. D 105, 123025 (2022)
“How effective is the BrinkAxel hypothesis for astrophysical weak rates?” N. Ali, J. Nabi, and C. W. Johnson, J. Phys. G. 49, 065201 (2022)
Feb 3, 2022: Preprint: "Collective neutrino oscillations with tensor networks using a timedependent variational principle," M. J. Cervia et al, arXiv:2202.01865
Jan 12, 2022: Preprint, "Nuclear states projected from a pair condensate," Y. Lu, Y. Lei, C. W. Johnson, J.J. Shen, arXiv:2112.15393.
Jan 3, 2022: Published: "Modified BrinkAxel hypothesis for astrophysical GamowTeller transitions," R. A. Herrera, C. W. Johnson, and G. M. Fuller, Phys. Rev. C 105, 015801.
August 19, 2021: Several new publications: “Lipkin model on a quantum computer,” M. J. Cervia, A. B. Balantekin, S. N. Coppersmith, C. W. Johnson, P.J. Love, C. Poole, K. Robbins, M. Saffman, Phys. Rev. C 104. 024305 (201)
“The nucleonpair approximation for nuclei from spherical to
deformed regions,” G.F. Fu and C. W. Johnson, Phys.
Rev. C 104 024312 (2021) “Editor’s
Suggestion”
“Benchmarking angularmomentum projected HartreeFock as an
approximation,” S. M. Lauber, H. C. Frye, and C. W.
Johnson, J.
Phys. G. 48, 095107 (2021).
June 24, 2021: Published B. Dai, B.S. Hu. Y.Z. Ma, J. G. Li, S. M. Wang, C. W. Johnson, and F. R. Xu, : “Tensor force role in bdecays analyzed within the Gognyinteraction shell model,” Phys. Rev. C 103, 064327 (2021).
May 19, 2021: Published: R. Zbikowski, C. W. Johnson, et al, "Rotational bands beyond the Elliott model," J. Phys. G 48, 075102 (2021).
May 16, 2021: I have been elected to the board of the FRIBTheory Alliance
Apr 8, 2021: Congratulations to Hayden Frye of our research group, named as the 2021 outstanding graduating physics student! Apr 8, 2021: A preprint Stephanie Lauber (Ph.D student), Hayden Frye (physics major), and C. W. Johnson, "Benchmarking projected HartreeFock as an approximation," arXiv:2104.03455.
Feb 15, 2021: Published: "Nucleonpair coupling scheme in Elliott's SU(3) model," G.J. Fu, C. W. Johnson, P. van Isacker, and Z.Z. Ren, Phys. Rev. C, 103, L021302 (2021)
Feb 8, 2020: A preprint from Ph.D student Oliver Gorton and J. Escher, "Cross sections for neutroninduced reactions from surrogate data," arXiv:2102.03452
Jan 27, 2021:, A preprint, "Nucleonpair coupling scheme in Elliott's SU(3) model," G.J. Fu, C. W. Johnson, P. van Isacker, and Z.Z. Ren, arXiv:2101.11774
Dec 17, 2020: A preprint: G. J. Fu and C. W. Johnson, "The nucleonpair approximation for nuclei from spherical to deformed reigions," arXiv: 2012.09560
Nov 24, 2020: Oliver Gorton, a Ph.D student in my group, is on a new paper just published "Measurements of proton capture in the A=100–110 mass region", PRC 102, 055806 (2020), OlivasGomez et al.
Nov 18, 2020: A preprint (accepted for publication by J. Phys. G): R. Zbikowski, C. W. Johnson, et al, "Rotational bands beyond the Elliott model," arXiv:2011.08307
Nov 16, 2020:
Another paper published, C. W. Johnson et al,
J.
Phys. G: Nucl. Part. Phys.
47 123001 (2020). White paper from
a workshop I ran two years ago.
Nov 6, 2020: A Nature News & Views article I wrote has been published.
October 5, 2020: Jordan Fox, Ph.D student, gets a SCGSR fellowship! This will allow him to carry out research at Lawrence Livermore National Lab.
September 18, 2020: A paper published, Exact sum rules with approximate ground states, C. W. Johnson. K. A. Luu, and Y. Lu, J. Phys G. 47 105107 (2020)
August 24, 2020: A paper published, From deformed HartreeFock to the nucleonpair approximation, G.J. Fu and C. W. Johnson, Phys. Lett. B 809, 135705 (2020)
May 11, 2020: A paper published, Uncertainty quantification of an empirical shellmodel interaction using principal component analysis, Jordan Fox, C. W. Johnson, and R. Navarro Perez, PRC 101, 054308 (2020), also available at arXiv:1911.05208.
April 29, 2020: A paper published, Unmixing symmetries, C. W. Johnson, PRL 124, 172502 (2020), also available at arXiv:1911.09142
April 2, 2020: I was named an outstanding review for Journal of Physics G: Nuclear Physics, for 2019.
Dec 3,2019: A paper published: "Nocore shell model calculations of the photonuclear cross section of 10B", M. K. G. Kruse, W.E. Ormand, and CWJ, EPJA 55, 225 (2019), and another paper posted: "From bound states to the continuum," arXiv:1912.00451
Nov 22, 2019: Two recent papers posted:
“Uncertainty
quantification of an empirical shellmodel interaction using
principal component analysis,” Jordan M. R. Fox and C.W.
Johnson,
arXiv:1911.05208
Sept 26, 2019: Paper
published (with modified title): "The
union of rotational and vibrational modes..." with C.F.
Jiao,
Phys.
Rev. C 100,
031303(R) (2019).
Sept 19, 2019: New paper on the arXiv: "From deformed HartreeFock to the nucleon pair approximation," (with G. J. Fu) arXiv: 1909.08785
Aug 12, 2019: Two papers on the arXiv: "The marriage of rotational and vibrational modes in generatorcoordinatetype calculations, with application to neutrinoless doublebeta decay" (with
C. F. Jiao) arXiv:1908.01873.
UPDATE 9/18/2019 accepted
Phys Rev C.
and
“Entanglement
and collective neutrino oscillations,” M. J. Cervia, A.
V. Patwardhan, A. B. Balantekin, S. N. Coppersmith, and CWJ,
arXiv:1908.03511. UPDATE 9/19/2019 accepted
Phys Rev. D. 100, 083001(2019)
Jul 12, 2019: Published article for
nonexperts: Shadows
of Symmetries,
Nuclear
Physics News International
29, 1821
(2019)(behind a paywall, I'm afraid to say)
Nov 20, 2018: Published paper: Convergence and efficiency of angular momentum projection ... J. Phys. G 46, 015101 (2019).
Sept 20, 2018: A new eprint conference
proceeding on largebasis diagonalization of the shell model.
Aug 20, 2018: A new eprint with Dr. Changfeng Jiao on
the arXiv:
“Convergence
and efficiency of angular momentum projection for manybody
systems” arXiv:1808.05672
July 1, 2018: I organized a twoweek workshop on Connecting Bound States to the Continuum, for FRIB at MSU June 1, 2018: Gave a short talk on the shell model at CIPANC 2018. Apr 9, 2018: I have been appointed an associate editor at Physical Review C Mar 29,2018: A paper, Transition sum rules in the shell model, has been published and is now online! Mar 2, 2018: I have been named an outstanding referee by the American Physical Society. Feb 27, 2018: My talk at TRIUMF on strength function sum rules is online. Jan
25, 2018: BIGSTICK, an
interacting shellmodel code, has finally been publically
released as free, opensource code!
Dec 1, 2017: A paper, Projection of angular momentum by linear algebra, cowritten with former SDSU physics major Kevin O'Mara, published and now online! Nov 27, 2017: Paper published: "Tracing the evolution of nuclear forces under the similarity renormalization group" Phys. Lett. B. 774, 465469 (2017). Oct 9, 2017: A new paper on the arXiv, "Transition sum rules in the shell model." Sept 14, 2017: My story, "Of the Beast in the Belly," has been anthologized in an audiobook collection, "Year's Top Hard Science Fiction Stories." Sept 13, 2017: A new paper on the arXiv, "Projection of angular momentum by linear algebra," cowritten with former SDSU physics major Kevin O'Mara: Update: accepted for publication in Phys. Rev. C! Sept 12, 2017: Congratulations to Raul Herrera, (UCSD physics grad student but part of my group) who has been awarded a U.S. Department of Energy (DOE) Office of Science Graduate Student Research (SCGSR) grant to spend 4 months at Lawrence Berkeley National Lab working on his thesis research, focusing on GamowTeller transitions above A = 65. These are highly competitive grants, and winning one is a tremendous achievement! Aug 9, 2017: I have a chapter in a book coming out, also available on the arXiv: "The anatomy of atomic nuclei." In addition, a new preprint is posted on the arXiv: "Tracing the evolution of nuclear forces under the similarity renormalization group" March 5, 2017: My talk "Ab initio rotational bands in medium and heavy nuclei" from the TRIUMF workshop on "Progress on Ab Initio Techniques in Nuclear Physics" on is now available online. Feb 22, 2017: Congratulations to Jordan Fox for winning a Parallel Computing Summer Research Internship at Los Alamos National Lab! Feb 3, 2017: The paper on backbending has been published and is selected as an Editor's suggestion! July 5, 2016: An eprint, "Quasidynamical symmetries in backbending the chromium isotopes," by Raul Herrera and C. W. Johnson has been posted on the arXiv. May, 2016: I have been awarded
30 MILLION corehours for computation
via ALCC
(ASCR Leadership Computing Challenge) Aug 31, 2015: "Systematics of strength function sum rules," : Phys. Lett. B 750, 72 (2015). March 11, 2015: "Spinorbit decomposition of ab initio nuclear wavefunctions" : Phys. Rev. C 91, 034313 (2015) November 5, 2014: I have a science fiction story appearing in the December issue of ANALOG SCIENCE FICTION AND FACT. You can read a sample of it here. August 18, 2014: I have started a blog, for posting essays on science, science fiction, and related topics. August 7, 2014: Micah Schuster (Ph.D student) wins award for best summer student research poster at Lawrence Livermore National Lab. He also won the past two years. Recent publications"Projection of angular momentum by linear algebra," C. W. Johnson and K. D. O'Mara, Phys. Rev. C 96, 064304 (2017)
"Quasidynamical symmetries in the chromium isotopes," R. Herrera and C. W. Johnson, Phys. Rev. C 95, 024303 (2017). "Systematics of strength function sum rules,": Phys. Lett. B 750, 72 (2015). "Spinorbit decomposition of ab initio nuclear wavefunctions" C. W. Johnson Phys. Rev. C 91, 034313 (2015) "Isoscalar and isovector pairing in a formalism of quartets," M. Sambataro, N. Sandulescu, and C. W. Johnson, Phys. Lett B 740, 137 (2015).
"Testing the spincutoff parameterization with shellmodel calculations," W. M. Spinella and C. W. Johnson, Phys. Rev. C 90, 014315 (2014), see also arXiv:1304.7746 "Operator evolution for ab initio theory of light nuclei" M. D. Schuster, S. Quaglioni, C. W. Johnson, E. D. Jurgenson, and P. Navratil, Phys. Rev. C 90, 011301(R) (2014), see also arXiv:1402:7106
"Factorization in largescale manybody calculations," C. W.
Johnson, W. E. Ormand, and P. G. Krastev, Comp.
Phys. Comm. 184, 27612774 (2013), see also arXiv:1303:0905
This paper describes the algorithms underlying the
Other recent writing"The Age of Discovery" (fiction, To Shape the Dark) "Of the Beast in the Belly" (fiction at Asimov's SF magazine) "Lives of the Elementary Particles" (fiction) "What the Higgs Boson Means to Me" (poetry) 
