Helicity-Dependent Cross Sections for the Photoproduction of π^{0} Pairs from Nucleons.,Physical Review Letters

当前位置： X-MOL 学术 › Phys. Rev. Lett. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Helicity-Dependent Cross Sections for the Photoproduction of π^{0} Pairs from Nucleons.
Physical Review Letters ( IF 8.1 ) Pub Date : 2020-08-05 , DOI: 10.1103/physrevlett.125.062001
M Dieterle ₁ , L Witthauer ₁ , A Fix ₂ , S Abt ₁ , P Achenbach ₃ , P Adlarson ₃ , F Afzal ₄ , P Aguar Bartolome ₃ , Z Ahmed ₅ , J R M Annand ₆ , H J Arends ₃ , M Bashkanov ₇ , R Beck ₄ , M Biroth ₃ , N Borisov ₈ , A Braghieri ₉ , W J Briscoe ₁₀ , F Cividini ₃ , C Collicott ₁₁ , S Costanza ₉ , A Denig ₃ , A S Dolzhikov ₈ , E J Downie ₁₀ , P Drexler _{3,

12} , S Gardner ₆ , D Ghosal ₁ , D I Glazier _{6,

7} , I Gorodnov ₈ , W Gradl ₃ , M Günther ₁ , D Gurevich ₁₃ , L Heijkenskjöld ₃ , D Hornidge ₁₄ , G M Huber ₅ , A Käser ₁ , V L Kashevarov _{3,

8} , S Kay ₇ , I Keshelashvili ₁ , R Kondratiev ₁₃ , M Korolija ₁₅ , B Krusche ₁ , A Lazarev ₈ , V Lisin ₁₃ , K Livingston ₆ , S Lutterer ₁ , I J D MacGregor ₆ , D M Manley ₁₆ , P P Martel _{3,

17} , V Metag ₁₂ , W Meyer ₁₈ , D G Middleton ₁₇ , R Miskimen ₁₉ , E Mornacchi ₃ , C Mullen ₆ , A Mushkarenkov _{9,

19} , A Neganov ₈ , A Neiser ₃ , M Oberle ₁ , M Ostrick ₃ , P B Otte ₃ , D Paudyal ₅ , P Pedroni ₉ , A Polonski ₁₃ , A Powell ₆ , S N Prakhov ₂₀ , G Reicherz ₁₈ , G Ron ₂₁ , T Rostomyan ₁ , A Sarty ₁₁ , C Sfienti ₃ , V Sokhoyan ₃ , K Spieker ₄ , O Steffen ₃ , I I Strakovsky ₁₀ , T Strub ₁ , I Supek ₁₅ , A Thiel ₄ , M Thiel ₃ , A Thomas ₃ , M Unverzagt ₃ , Yu A Usov ₈ , S Wagner ₃ , N K Walford ₁ , D P Watts ₇ , D Werthmüller _{1,

6} , J Wettig ₃ , M Wolfes ₃ , L A Zana ₇ ,

Affiliation

Department of Physics, University of Basel, CH-4056 Basel, Switzerland.
Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634034 Tomsk, Russia.
Institut für Kernphysik, University of Mainz, D-55099 Mainz, Germany.
Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, D-53115 Bonn, Germany.
University of Regina, Regina, Saskatchewan S4S-0A2 Canada.
SUPA School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
SUPA School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom.
Joint Institute for Nuclear Research, 141980 Dubna, Russia.
INFN Sezione di Pavia, I-27100 Pavia, Pavia, Italy.
Center for Nuclear Studies, The George Washington University, Washington, DC 20052, USA.
Department of Astronomy and Physics, Saint Mary's University, E4L1E6 Halifax, Canada.
II. Physikalisches Institut, University of Giessen, D-35392 Giessen, Germany.
Institute for Nuclear Research, RU-125047 Moscow, Russia.
Mount Allison University, Sackville, New Brunswick E4L1E6, Canada.
Rudjer Boskovic Institute, HR-10000 Zagreb, Croatia.
Kent State University, Kent, Ohio 44242, USA.
Mount Allison University, Sackville, New Brunswick E4L3B5, Canada.
Institut für Experimentalphysik, Ruhr Universität, 44780 Bochum, Germany.
University of Massachusetts, Amherst, Massachusetts 01003, USA.
University of California Los Angeles, Los Angeles, California 90095-1547, USA.
Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904, Israel.

The double-polarization observable

E

and helicity-dependent cross sections

σ_{1 / 2}

σ_{3 / 2}

have been measured for the photoproduction of

π^{0}

pairs off quasifree protons and neutrons at the Mainz MAMI accelerator with the Crystal Ball/TAPS setup. A circularly polarized photon beam was produced by bremsstrahlung from longitudinally polarized electrons and impinged on a longitudinally polarized deuterated butanol target. The reaction products were detected with an almost

4 π

covering calorimeter. The results reveal for the first time the helicity- and isospin-dependent structure of the

γ N \to N π^{0} π^{0}

reaction. They are compared to predictions from reaction models in view of nucleon resonance contributions and also to a refit of one model that predicted results for the proton and for the neutron target. The comparison of the prediction and the refit demonstrates the large impact of the new data.

中文翻译：