Quarks, Hadrons and Nuclei

Gernot Eichmann

The building blocks of matter

We investigate how the fundamental constituents of matter – quarks and gluons – bind together to form hadrons and nuclei. The underlying theory of the strong interaction, Quantum Chromodynamics (QCD), shows many interesting non-perturbative phenomena like confinement, dynamical mass generation and the formation of bound states and resonances, which are not yet fully understood. One particularly exciting possibility is the existence of exotic hadrons such as tetraquarks, pentaquarks and other unconventional systems. To study them, we employ numerical simulations using functional methods, e.g., in the form of Dyson-Schwinger equations and covariant Bethe-Salpeter and Faddeev equations.

We are part of the ExoHad collaboration, a Topical Collaboration formed in 2023 to investigate exotic hadrons.

 

If you are interested in bachelor, master or PhD theses in our group, please contact me via email or in my office.

 

Quarks, Hadrons and Nuclei ©Uni Graz/Eichmann

Teaching

Winter term 2023/24

  • Funktionalanalysis, Tue & Thu 8:30 - 9:45, HS 05.01

  • Master seminar in Particle Physics, Thu 10:45 - 12:15, SR 05.11

Summer term 2023

  • Kern- und Teilchenphysik für Lehramt, Mo 17:15 - 18:45, HS 05.12

  • Fortgeschrittene Programmierung in der Physik

Winter term 2022/23

  • Functional methods, Mo 13:30 - 15:00, SR 05.11

  • Master seminar in Particle Physics, Mo 15:30 - 17:00, SR 15.47 (RESOWI, Block D, 4th floor)

 

Lecture notes

Publications

The publication list is also available from INSPIRE.

  1. The structure of open-flavour four-quark states in the charm and bottom region
    J. Hoffer, G. Eichmann, C. S. Fischer
    e-Print: 2409.05779 [hep-ph].
     
  2. Hidden-flavor four-quark states in the charm and bottom region
    Joshua Hoffer, Gernot Eichmann, Christian S. Fischer
    e-Print: 2402.12830 [hep-ph].
     
  3. Bound states from the spectral Bethe-Salpeter equation
    Gernot Eichmann, Andrés Gómez, Jan Horak, Jan M. Pawlowski, Jonas Wessely, Nicolas Wink
    e-Print: 2310.16353 [hep-ph].
     
  4. Strong Interaction Physics at the Luminosity Frontier with 22 GeV Electrons at Jefferson Lab
    A. Accardi, P. Achenbach, D. Adhikari, A. Afanasev, C. S. Akondi, et al.
    e-Print: 2306.09360 [hep-ph].
     
  5. The case for an EIC Theory Alliance: Theoretical Challenges of the EIC
    Raktim Abir, Igor Akushevich, Tolga Altinoluk, Daniele Paolo Anderle, Fatma P. Aslan, et al.
    e-Print: 2305.14572 [hep-ph].
     
  6. Heavy Baryon Spectroscopy in a Quark–Diquark Approach
    André Torcato, Ana Arriaga, Gernot Eichmann, Teresa Peña
    Few Body Syst. 64 (2023) 3, 45
    e-Print: 2202.13378 [hep-ph].
     
  7. Theory introduction to baryon spectroscopy
    Gernot Eichmann
    Few Body Syst. 63 (2022) 3, 57
    e-Print: 2202.13378 [hep-ph].
     
  8. Going to the light front with contour deformations
    Gernot Eichmann, Eduardo Ferreira, Alfred Stadler
    Phys. Rev. D 105 (2022) 3, 034009
    e-Print: 2112.04858 [hep-ph].
     
  9. On mass generation in Landau-gauge Yang-Mills theory
    Gernot Eichmann, Jan M. Pawlowski, João M. Silva
    Phys. Rev. D 104 (2021) 11, 114016
    e-Print: 2107.05352 [hep-ph].
     
  10. Four-quark states from functional methods
    Gernot Eichmann, Christian S. Fischer, Walter Heupel, Nico Santowsky, Paul C. Wallbott,
    Few Body Syst. 61 (2020) 4, 38
    e-Print: 2008.10240 [hep-ph].
     
  11. Diquark Correlations in Hadron Physics: Origin, Impact and Evidence
    M. Yu. Barabanov, M. A. Bedolla, W. K. Brooks, G. D. Cates, C. Chen et al.
    Prog. Part. Nucl. Phys. 116 (2021) 103835
    e-Print: 2008.07630 [hep-ph].
     
  12. The σ-meson: four-quark vs. two-quark components and decay width in a Bethe-Salpeter approach
    Nico Santowsky, Gernot Eichmann, Christian S. Fischer, Paul C. Wallbott, Richard Williams, Phys. Rev. D 102 (2020) 5, 056014
    e-Print: 2007.06495 [hep-ph].
     
  13. The anomalous magnetic moment of the muon in the Standard Model
    T. Aoyama, N. Asmussen, M. Benayoun, J. Bijnens, T. Blum et al.
    Phys. Rept. 887 (2020) 1-166
    e-Print: 2006.04822 [hep-ph].
     
  14. Disentangling different structures in heavy-light four-quark states
    Paul C. Wallbott, Gernot Eichmann, Christian S. Fischer
    Accepted for publication in Phys. Rev. D Rapid Comm.
    Phys. Rev.D 102 (2020) 5, 051501
    e-Print: 2003.12407 [hep-ph].
     
  15. Kaon-box contribution to the anomalous magnetic moment of the muon
    Gernot Eichmann, Christian S. Fischer, Richard Williams
    Phys.Rev. D101 (2020) no.5, 054015
    e-Print: 1910.06795 [hep-ph].
     
  16. Scattering amplitudes and contour deformations
    Gernot Eichmann, Pedro Duarte, M. T. Peña, Alfred Stadler
    Phys.Rev. D100 (2019) no.9, 094001
    e-Print: 1907.05402 [hep-ph].
     
  17. X(3872) as a four-quark state in a Dyson-Schwinger/
    Bethe-Salpeter approach
    Paul C. Wallbott, Gernot Eichmann, Christian S. Fischer
    Phys.Rev. D100 (2019) no.1, 014033
    e-Print: 1905.02615 [hep-ph].
     
  18. Single pseudoscalar meson pole and pion box contributions
    to the anomalous magnetic moment of the muon
    Gernot Eichmann, Christian S. Fischer, Esther Weil, Richard Williams
    Phys.Lett. B797 (2019) 134855
    e-Print: 1903.10844 [hep-ph].
     
  19. Baryon Structure and reactions from Dyson-Schwinger equations
    Gernot Eichmann, Christian S. Fischer
    Few Body Syst. 60 (2019) no.1, 2.
     
  20. Nucleon resonances in Compton scattering
    Gernot Eichmann, Gilberto Ramalho
    Phys.Rev. D98 (2018) no.9, 093007
    e-Print: 1806.04579 [hep-ph].
     
  21. Electromagnetic decays of the neutral pion
    Esther Weil, Gernot Eichmann, Christian S. Fischer, Richard Williams
    Phys.Rev. D96 (2017) no.1, 014021
    e-Print: 1704.06046 [hep-ph].
     
  22. On the large-Q2 behavior of the pion transition form factor
    Gernot Eichmann, Christian S. Fischer, Esther Weil, Richard Williams
    Phys.Lett. B774 (2017) 425-429
    e-Print: 1704.05774 [hep-ph].
     
  23. More about the light baryon spectrum
    Gernot Eichmann
    Few Body Syst. 58 (2017) no. 2, 81
    e-Print: 1611.10118 [hep-ph].
     
  24. On light baryons and their excitations
    Gernot Eichmann, Christian S. Fischer, Helios Sanchis-Alepuz
    Phys. Rev. D94 (2016) 9, 094033
    e-Print: 1607.05748 [hep-ph].
     
  25. Baryons as relativistic three-quark bound states
    Gernot Eichmann, Helios Sanchis-Alepuz, Richard Williams, Reinhard Alkofer,
    Christian S. Fischer. Prog. Part. Nucl. Phys. 91 (2016) 1-100
    e-Print: 1606.09602 [hep-ph].
     
  26. Progress in the calculation of nucleon transition form factors
    Gernot Eichmann
    Few Body Syst. 57 (2016) no. 10, 965-973
    e-Print: 1602.03462 [hep-ph].
     
  27. Towards a microscopic understanding of nucleon polarizabilities
    Gernot Eichmann
    Few Body Syst. 57 (2016) no. 7, 541-547
    e-Print: 1601.04154 [hep-ph].
     
  28. Baryon effects on the location of QCD's critical end point
    Gernot Eichmann, Christian S. Fischer, Christian A. Welzbacher
    Phys. Rev. D93 (2016) 3, 034013
    e-Print: 1509.02082 [hep-ph].
     
  29. The light scalar mesons as tetraquarks
    Gernot Eichmann, Christian S. Fischer, Walter Heupel
    Phys. Lett. B753 (2016) 282-287
    e-Print: 1508.07178 [hep-ph].
     
  30. Four-point functions and the permutation group S4
    Gernot Eichmann, Christian S. Fischer, Walter Heupel
    Phys. Rev. D92 (2015) 5, 056005
    e-Print: 1505.06336 [hep-ph].
     
  31. Electromagnetic baryon form factors in the Poincaré-covariant Faddeev approach
    Reinhard Alkofer, Gernot Eichmann, Helios Sanchis-Alepuz, Richard Williams
    Hyperfine Interact. 234 (2015) 1-3, 149-154
    e-Print: 1412.8413 [hep-ph].
     
  32. The three-gluon vertex in Landau gauge
    Gernot Eichmann, Richard Williams, Reinhard Alkofer, Milan Vujinovic
    Phys. Rev. D89, 105014 (2014)
    e-Print: 1402.1365 [hep-ph].
     
  33. Nucleon Compton scattering in the Dyson-Schwinger approach
    Gernot Eichmann, Christian S. Fischer
    Phys. Rev. D87, 036006 (2013)
    e-Print: 1212.1761 [hep-ph].
     
  34. Tetraquark bound states in a Bethe-Salpeter approach
    Walter Heupel, Gernot Eichmann, Christian S. Fischer
    Phys.Lett. B718, 545 (2012)
    e-Print: 1206.5129 [hep-ph].
     
  35. Nucleon to Delta electromagnetic transition in the Dyson-Schwinger approach
    Gernot Eichmann, Diana Nicmorus
    Phys. Rev. D85, 093004 (2012)
    e-Print: 1112.2232 [hep-ph].
     
  36. Nucleon axial and pseudoscalar form factors
    from the covariant Faddeev equation
    Gernot Eichmann, Christian S. Fischer
    Eur. Phys. J. A 48 (2011) 9
    e-Print: 1111.2614 [hep-ph].
     
  37. Unified description of hadron-photon and hadron-meson scattering
    in the Dyson-Schwinger approach
    Gernot Eichmann, Christian S. Fischer
    Phys. Rev. D85, 034015 (2012)
    e-Print: 1111.0197 [hep-ph].
     
  38. Delta and Omega masses in a three-quark covariant Faddeev approach
    Helios Sanchis-Alepuz, Gernot Eichmann, Selym Villalba-Chavez, Reinhard Alkofer
    Phys. Rev. D84, 096003 (2011)
    e-Print: 1109.0199 [hep-ph].
     
  39. Hadronic decays of mesons and baryons in the Dyson-Schwinger approach
    Valentin Mader, Gernot Eichmann, Martina Blank, Andreas Krassnigg
    Phys. Rev. D84, 034012 (2011)
    e-Print: 1106.3159 [hep-ph].
     
  40. Nucleon electromagnetic form factors from the covariant Faddeev equation
    Gernot Eichmann
    Phys. Rev. D84, 014014 (2011)
    e-Print: 1104.4505 [hep-ph].
     
  41. Delta and Omega electromagnetic form factors in a
    Dyson-Schwinger/Bethe-Salpeter approach
    Diana Nicmorus, Gernot Eichmann, Reinhard Alkofer
    Phys.Rev. D82, 114017 (2010)
    e-Print: 1008.3184 [hep-ph].
     
  42. Delta properties in the rainbow-ladder truncation
    of Dyson-Schwinger equations
    D. Nicmorus, G. Eichmann, A. Krassnigg, R. Alkofer.
    Few Body Syst. 49, 255-261 (2011)
    e-Print: 1008.4149 [hep-ph].
     
  43. Nucleon mass from a covariant three-quark Faddeev equation
    Gernot Eichmann, Reinhard Alkofer, Andreas Krassnigg, Diana Nicmorus
    Phys. Rev. Lett. 104, 201601 (2010)
    e-Print: 0912.2246 [hep-ph].
     
  44. Delta-baryon mass in a covariant Faddeev approach
    D. Nicmorus, G. Eichmann, A. Krassnigg, R. Alkofer.
    Phys. Rev. D80, 054028 (2009)
    e-Print: 0812.1665 [hep-ph].
     
  45. Survey of nucleon electromagnetic form factors
    I.C. Cloet, G. Eichmann, B. El-Bennich, T. Klahn, C.D. Roberts.
    Few Body Syst. 46, 1-36 (2009)
    e-Print: 0812.0416 [nucl-th].
     
  46. Toward unifying the description of meson and baryon properties
    G. Eichmann, I.C. Cloet, R. Alkofer, A. Krassnigg, C.D. Roberts.
    Phys. Rev. C79, 012202(R) (2009)
    e-Print: 0810.1222 [nucl-th].
     
  47. Current quark mass dependence of nucleon magnetic moments and radii
    I.C. Cloet, G. Eichmann, V.V. Flambaum, C.D. Roberts, M.S. Bhagwat, A. Holl.
    Few Body Syst. 42, 91-113 (2008)
    e-Print: 0804.3118 [nucl-th].
     
  48. Perspective on rainbow-ladder truncation
    G. Eichmann, R. Alkofer, I. C. Cloet, A. Krassnigg, C. D. Roberts.
    Phys. Rev. C77, 042202(R) (2008)
    e-Print: 0802.1948 [nucl-th].
     
  49. A covariant view on the nucleons' quark core
    G. Eichmann, A. Krassnigg, M. Schwinzerl and R. Alkofer.
    Annals Phys. 323, 2505-2553 (2008)
    e-Print: 0712.2666 [hep-ph].

 

Conference proceedings

 

  1. Studying mass generation for gluons
    Gernot Eichmann, Jan M. Pawlowski
    e-Print: 2112.08058 [hep-ph].
     
  2. Hadron Spectroscopy and Structure in the Dyson-Schwinger Approach
    Gernot Eichmann
    Springer Proc. Phys. 238 (2020) 783-792.
     
  3. Towards Heavy-Light Axialvector Tetraquarks in a
    Dyson-Schwinger/Bethe--Salpeter Approach
    Paul C. Wallbott, Gernot Eichmann, Christian S. Fischer
    Acta Phys. Polon. Supp. 13 (2020) 139.
     
  4. Towards resonance properties in the Dyson-Schwinger approach
    Gernot Eichmann
    PoS LC2019 (2019) 003.
    e-Print: 1912.08873 [hep-ph].
     
  5. Towards lattice-assisted hadron physics calculations based on
    QCD n-point functions
    André Sternbeck, Milena Leutnant, Gernot Eichmann
    PoS LATTICE2018 (2019) 068.
    e-Print: 1904.10705 [hep-lat].
     
  6. Light tetraquarks in a Dyson-Schwinger/Bethe-Salpeter approach
    Paul C. Wallbott, Gernot Eichmann, Christian S. Fischer
    J. Phys. Conf. Ser. 1024 (2018) 1, 012035.
     
  7. Overview of multiquark states
    Christian S. Fischer, Gernot Eichmann
    PoS Hadron2017 (2018) 007.
     
  8. Electromagnetic decays of the neutral pion investigated in the Dyson-Schwinger formalism
    Esther Weil, Gernot Eichmann, Christian S. Fischer, Richard Williams
    J. Phys. Conf. Ser. 1024 (2018) 1, 012035.
    e-Print: 1710.08169 [hep-ph].
     
  9. Tetraquarks from the Bethe-Salpeter equation
    Gernot Eichmann, Christian S. Fischer, Walter Heupel
    Acta Phys.Polon.Supp. 8 (2015) 425
    e-Print: 1507.05022 [hep-ph].
     
  10. Hadron properties from the Dyson-Schwinger approach
    Gernot Eichmann
    MesonNet 2014 International Workshop. Mini-proceedings
    e-Print: 1412.5451 [nucl-ex].
     
  11. The muon g-2: Dyson-Schwinger status on hadronic light-by-light scattering
    Gernot Eichmann, Christian S. Fischer, Walter Heupel, Richard Williams
    Proceedings of Confinement XI
    AIP Conf. Proc. 1701, 040004 (2016).
    e-Print: 1411.7876 [hep-ph].
     
  12. Non-perturbative features of the three-gluon vertex in Landau gauge
    Milan Vujinovic, Reinhard Alkofer, Gernot Eichmann, Richard Williams
    Proceedings of Excited QCD 2014
    Acta Phys. Polon. Supp. 7 (2014) 3, 607.
    e-Print: 1404.4474 [hep-ph].
     
  13. Probing nucleons with photons at the quark level
    Gernot Eichmann
    Proceedings of Excited QCD 2014
    Acta Phys. Polon. Supp. 7 (2014) 3, 597.
    e-Print: 1404.4149 [hep-ph].
     
  14. On propagators and three-point functions in Landau gauge QCD
    and QCD-like theories
    Reinhard Alkofer, Gernot Eichmann, Christian S. Fischer, Markus Hopfer,
    Milan Vujinovic, Richard Williams, Andreas Windisch
    PoS QCD-TNT-III (2013) 003
    e-Print: 1405.7310 [hep-ph].
     
  15. The role of pions as virtual constituents of light bound states
    Walter Heupel, Stanislav Kubrak, Gernot Eichmann, Christian Fischer
    PoS Bormio2013 (2013) 065
    e-Print: 1305.0650 [hep-ph].
     
  16. Hadron phenomenology in the Dyson-Schwinger approach
    Gernot Eichmann
    Proceedings of FAIRNESS 2012
    J. Phys. Conf. Ser. 426 (2013) 012014.
     
  17. Nucleon Compton scattering from the Dyson-Schwinger perspective
    Gernot Eichmann, Christian S. Fischer
    PoS ConfinementX (2012) 090
    e-Print: 1301.1194 [hep-ph].
     
  18. From quarks and gluons to baryon form factors
    Gernot Eichmann
    Erice Proceedings, 33rd International Workshop on Nuclear Physics
    Prog. Part. Nucl. Phys. 67 (2012) 234.
     
  19. Baryon form factors from Dyson-Schwinger equations
    Gernot Eichmann
    PoS QCD-TNT-II (2011) 017
    e-Print: 1112.4888 [hep-ph].
     
  20. Model comparison of Delta and Omega masses
    in a covariant Faddeev approach
    H. Sanchis-Alepuz, R. Alkofer, G. Eichmann, R. Williams.
    PoS QCD-TNT-II (2011) 041
    e-Print: 1112.3214 [hep-ph].
     
  21. On baryon properties from a covariant Faddeev approach
    H. Sanchis-Alepuz, R. Alkofer, G. Eichmann, S. Villalba-Chavez.
    PoS LC 2010 018 (2010)
    e-Print: 1010.6183 [hep-ph].
     
  22. Baryons in and beyond the quark-diquark model
    G. Eichmann, R. Alkofer, C. S. Fischer, A. Krassnigg, D. Nicmorus.
    AIP Conf. Proc. 1374 (2011) 617-620
    e-Print: 1010.0206 [hep-ph].
     
  23. Hadron properties from QCD bound-state equations: A status report
    R. Alkofer, G. Eichmann, A. Krassnigg, D. Nicmorus.
    Chin. Phys. C34, 1175-1180 (2010)
    e-Print: 0912.3105 [hep-ph].
     
  24. Covariant solution of the three-quark problem in quantum field theory:
    the nucleon
    G. Eichmann, R. Alkofer, A. Krassnigg, D. Nicmorus
    EPJ Web Conf. 3:03028 (2010)
    e-Print: 0912.2876 [hep-ph].
     
  25. Meson and nucleon properties from Dyson-Schwinger QCD
    G. Eichmann, R. Alkofer, A. Krassnigg, D. Nicmorus.
    PoS CONFINEMENT8 077 (2008)
    e-Print: 0812.3183 [hep-ph].
     
  26. Faddeev equations: A view of baryon properties
    D. Nicmorus, G. Eichmann, A. Krassnigg, R. Alkofer.
    PoS CONFINEMENT8 052 (2008)
    e-Print: 0812.2966 [hep-ph].
     
  27. The nucleon as a QCD bound state in a Faddeev approach
    G. Eichmann, A. Krassnigg, M. Schwinzerl and R. Alkofer.
    Prog. Part. Nucl. Phys. 61:84-85 (2008)

Presentations

 

→ Full list

Conferences and workshops

... organized by members of our group:

Team

Ass.-Prof. Dr.
Gernot Eichmann

Group leader
gernot.eichmann(at)uni-graz.at

+43 316 380 - 5244
Institut für Physik, Universitätsplatz 5, 8010 Graz
Office: Room 1-26

Msc.
Eduardo Ferreira

PhD student
eduardo.ferreira(at)uni-graz.at

+43 316 380 - 5089
Mozartgasse 14/II, 8010 Graz
Light-front wave functions, parton distributions

Msc.
Raúl Torres

PhD student
raul.torres(at)umich.mx

LIP Lisboa, Av. Prof. Gama Pinto 2, 1649-003 Lisboa, Portugal
Pentaquarks, meson spectroscopy, flavor matrix elements

Msc.
André Torcato

PhD student
atorcato(at)lip.pt

LIP Lisboa, Av. Prof. Gama Pinto 2, 1649-003 Lisboa, Portugal
Heavy-baryon spectroscopy

André Nunes

Master student
fc52868(at)alunos.ciencias.ulisboa.pt

FCUL Lisboa, Campo Grande 016, 1749-016 Lisboa, Portugal
Six-quark states and the deuteron

Felix Halbwedl

Master student
felix.halbwedl(at)edu.uni-graz.at

+43 316 380 - 5089
Mozartgasse 14/II, 8010 Graz
Analytic structure of correlation functions
Luca Oberguggenberger

Luca Oberguggenberger

Master student
Baryons with higher spin
Matthias Staffler

Matthias Staffler

Master student
Baryons at nonzero chemical potential
Paul Mirtl

Paul Mirtl

Bachelor student
Nucleon-nucleon scattering
Kaja Karabašević

Kaja Karabašević

Bachelor student
Pentaquarks
Oliver Regenfelder

Oliver Regenfelder

Bachelor student
Muon g-2

Guests and Visitors

  • An Di, University of Uppsala, Sweden (Dec 2023 - Jan 2024)
  • Joshua Hoffer, University of Giessen, Germany (March & July/August 2023)
  • Duifje van Egmond, Institute Polytechnique de Paris, France (Jan 2023)

Completed theses

  • André Nunes (FCUL Lisboa) - master, completed 2024 (Thesis)
  • André Torcato (FCUL Lisboa) - master, completed 2022 (Thesis, LIP News)
  • Eduardo Ferreira (IST Lisboa) - master, completed 2021 (Thesis, LIP News)
  • Madalena Lourenço (IST Lisboa) - master, completed 2021 (Thesis)

International Collaborations