Narrow Structure in the Excitation Function of eta Photoproduction off the Neutron

A2 Collaboration; D. Werthmueller; L. Witthauer; I. Keshelashvili; P. Aguar-Bartolome; J. Ahrens; J. R. M. Annand; H. J. Arends; K. Bantawa; R. Beck; V. Bekrenev; A. Braghieri; D. Branford; W. J. Briscoe; J. Brudvik; S. Cherepnya; B. Demissie; M. Dieterle; E. J. Downie; P. Drexler; L. V. Fil'kov; A. Fix; D. I. Glazier; D. Hamilton; E. Heid; D. Hornidge; D. Howdle; G. M. Huber; I. Jaegle; O. Jahn; T. C. Jude; A. Kaeser; V. L. Kashevarov; R. Kondratiev; M. Korolija; S. P. Kruglov; B. Krusche; A. Kulbardis; V. Lisin; K. Livingston; I. J. D. MacGregor; Y. Maghrbi; J. Mancell; D. M. Manley; Z. Marinides; M. Martinez; J. C. McGeorge; E. F. McNicoll; S. Schumann; M. H. Sikora; D. P. Watts

doi:10.1103/PhysRevLett.111.232001

Narrow Structure in the Excitation Function of eta Photoproduction off the Neutron

A2 Collaboration, D. Werthmueller, L. Witthauer, I. Keshelashvili, P. Aguar-Bartolome, J. Ahrens, J. R. M. Annand, H. J. Arends, K. Bantawa, R. Beck, V. Bekrenev, A. Braghieri, D. Branford, W. J. Briscoe, J. Brudvik, S. Cherepnya, B. Demissie, M. Dieterle, E. J. Downie, P. DrexlerL. V. Fil'kov, A. Fix, D. I. Glazier, D. Hamilton, E. Heid, D. Hornidge, D. Howdle, G. M. Huber, I. Jaegle, O. Jahn, T. C. Jude, A. Kaeser, V. L. Kashevarov, R. Kondratiev, M. Korolija, S. P. Kruglov, B. Krusche^*, A. Kulbardis, V. Lisin, K. Livingston, I. J. D. MacGregor, Y. Maghrbi, J. Mancell, D. M. Manley, Z. Marinides, M. Martinez, J. C. McGeorge, E. F. McNicoll, S. Schumann, M. H. Sikora, D. P. Watts

^*Corresponding author for this work

School of Physics and Astronomy

Research output: Contribution to journal › Article › peer-review

Abstract / Description of output

The photoproduction of eta mesons off nucleons bound in H-2 and He-3 has been measured in coincidence with recoil protons and recoil neutrons for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI accelerator, using the Glasgow tagged photon facility. Decay photons from the eta -> 2 gamma and eta -> 3 pi(0) decays and the recoil nucleons were detected with an almost 4 pi electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets are of excellent statistical quality and show a narrow structure in the excitation function of gamma n -> n eta. The results from the two measurements are consistent, taking into account the expected effects from nuclear Fermi motion. The best estimates for position and intrinsic width of the structure are W = (1670 +/- 5) MeV and Gamma = (30 +/- 15) MeV. For the first time precise results for the angular dependence of this structure have been extracted.

Original language	English
Article number	232001
Number of pages	5
Journal	Physical Review Letters
Volume	111
Issue number	23
DOIs	https://doi.org/10.1103/PhysRevLett.111.232001
Publication status	Published - 4 Dec 2013

Keywords / Materials (for Non-textual outputs)

NEAR-THRESHOLD PHOTOPRODUCTION
COHERENT PHOTOPRODUCTION
EXCLUSIVE MEASUREMENT
RESONANCE REGION
MESONS
DEUTERON
NUCLEON
PROTON
MODEL

Access to Document

10.1103/PhysRevLett.111.232001

Cite this

A2 Collaboration, Werthmueller, D., Witthauer, L., Keshelashvili, I., Aguar-Bartolome, P., Ahrens, J., Annand, J. R. M., Arends, H. J., Bantawa, K., Beck, R., Bekrenev, V., Braghieri, A., Branford, D., Briscoe, W. J., Brudvik, J., Cherepnya, S., Demissie, B., Dieterle, M., Downie, E. J., ... Watts, D. P. (2013). Narrow Structure in the Excitation Function of eta Photoproduction off the Neutron. Physical Review Letters, 111(23), Article 232001. https://doi.org/10.1103/PhysRevLett.111.232001

@article{d58ed025a33a4390bf814d4ef89dd146,

title = "Narrow Structure in the Excitation Function of eta Photoproduction off the Neutron",

abstract = "The photoproduction of eta mesons off nucleons bound in H-2 and He-3 has been measured in coincidence with recoil protons and recoil neutrons for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI accelerator, using the Glasgow tagged photon facility. Decay photons from the eta -> 2 gamma and eta -> 3 pi(0) decays and the recoil nucleons were detected with an almost 4 pi electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets are of excellent statistical quality and show a narrow structure in the excitation function of gamma n -> n eta. The results from the two measurements are consistent, taking into account the expected effects from nuclear Fermi motion. The best estimates for position and intrinsic width of the structure are W = (1670 +/- 5) MeV and Gamma = (30 +/- 15) MeV. For the first time precise results for the angular dependence of this structure have been extracted.",

keywords = "NEAR-THRESHOLD PHOTOPRODUCTION, COHERENT PHOTOPRODUCTION, EXCLUSIVE MEASUREMENT, RESONANCE REGION, MESONS, DEUTERON, NUCLEON, PROTON, MODEL",

author = "{A2 Collaboration} and D. Werthmueller and L. Witthauer and I. Keshelashvili and P. Aguar-Bartolome and J. Ahrens and Annand, {J. R. M.} and Arends, {H. J.} and K. Bantawa and R. Beck and V. Bekrenev and A. Braghieri and D. Branford and Briscoe, {W. J.} and J. Brudvik and S. Cherepnya and B. Demissie and M. Dieterle and Downie, {E. J.} and P. Drexler and Fil'kov, {L. V.} and A. Fix and Glazier, {D. I.} and D. Hamilton and E. Heid and D. Hornidge and D. Howdle and Huber, {G. M.} and I. Jaegle and O. Jahn and Jude, {T. C.} and A. Kaeser and Kashevarov, {V. L.} and R. Kondratiev and M. Korolija and Kruglov, {S. P.} and B. Krusche and A. Kulbardis and V. Lisin and K. Livingston and MacGregor, {I. J. D.} and Y. Maghrbi and J. Mancell and Manley, {D. M.} and Z. Marinides and M. Martinez and McGeorge, {J. C.} and McNicoll, {E. F.} and S. Schumann and Sikora, {M. H.} and Watts, {D. P.}",

year = "2013",

month = dec,

day = "4",

doi = "10.1103/PhysRevLett.111.232001",

language = "English",

volume = "111",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "23",

}

A2 Collaboration, Werthmueller, D, Witthauer, L, Keshelashvili, I, Aguar-Bartolome, P, Ahrens, J, Annand, JRM, Arends, HJ, Bantawa, K, Beck, R, Bekrenev, V, Braghieri, A, Branford, D, Briscoe, WJ, Brudvik, J, Cherepnya, S, Demissie, B, Dieterle, M, Downie, EJ, Drexler, P, Fil'kov, LV, Fix, A, Glazier, DI, Hamilton, D, Heid, E, Hornidge, D, Howdle, D, Huber, GM, Jaegle, I, Jahn, O, Jude, TC, Kaeser, A, Kashevarov, VL, Kondratiev, R, Korolija, M, Kruglov, SP, Krusche, B, Kulbardis, A, Lisin, V, Livingston, K, MacGregor, IJD, Maghrbi, Y, Mancell, J, Manley, DM, Marinides, Z, Martinez, M, McGeorge, JC, McNicoll, EF, Schumann, S, Sikora, MH & Watts, DP 2013, 'Narrow Structure in the Excitation Function of eta Photoproduction off the Neutron', Physical Review Letters, vol. 111, no. 23, 232001. https://doi.org/10.1103/PhysRevLett.111.232001

TY - JOUR

T1 - Narrow Structure in the Excitation Function of eta Photoproduction off the Neutron

AU - A2 Collaboration

AU - Werthmueller, D.

AU - Witthauer, L.

AU - Keshelashvili, I.

AU - Aguar-Bartolome, P.

AU - Ahrens, J.

AU - Annand, J. R. M.

AU - Arends, H. J.

AU - Bantawa, K.

AU - Beck, R.

AU - Bekrenev, V.

AU - Braghieri, A.

AU - Branford, D.

AU - Briscoe, W. J.

AU - Brudvik, J.

AU - Cherepnya, S.

AU - Demissie, B.

AU - Dieterle, M.

AU - Downie, E. J.

AU - Drexler, P.

AU - Fil'kov, L. V.

AU - Fix, A.

AU - Glazier, D. I.

AU - Hamilton, D.

AU - Heid, E.

AU - Hornidge, D.

AU - Howdle, D.

AU - Huber, G. M.

AU - Jaegle, I.

AU - Jahn, O.

AU - Jude, T. C.

AU - Kaeser, A.

AU - Kashevarov, V. L.

AU - Kondratiev, R.

AU - Korolija, M.

AU - Kruglov, S. P.

AU - Krusche, B.

AU - Kulbardis, A.

AU - Lisin, V.

AU - Livingston, K.

AU - MacGregor, I. J. D.

AU - Maghrbi, Y.

AU - Mancell, J.

AU - Manley, D. M.

AU - Marinides, Z.

AU - Martinez, M.

AU - McGeorge, J. C.

AU - McNicoll, E. F.

AU - Schumann, S.

AU - Sikora, M. H.

AU - Watts, D. P.

PY - 2013/12/4

Y1 - 2013/12/4

N2 - The photoproduction of eta mesons off nucleons bound in H-2 and He-3 has been measured in coincidence with recoil protons and recoil neutrons for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI accelerator, using the Glasgow tagged photon facility. Decay photons from the eta -> 2 gamma and eta -> 3 pi(0) decays and the recoil nucleons were detected with an almost 4 pi electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets are of excellent statistical quality and show a narrow structure in the excitation function of gamma n -> n eta. The results from the two measurements are consistent, taking into account the expected effects from nuclear Fermi motion. The best estimates for position and intrinsic width of the structure are W = (1670 +/- 5) MeV and Gamma = (30 +/- 15) MeV. For the first time precise results for the angular dependence of this structure have been extracted.

AB - The photoproduction of eta mesons off nucleons bound in H-2 and He-3 has been measured in coincidence with recoil protons and recoil neutrons for incident photon energies from threshold up to 1.4 GeV. The experiments were performed at the Mainz MAMI accelerator, using the Glasgow tagged photon facility. Decay photons from the eta -> 2 gamma and eta -> 3 pi(0) decays and the recoil nucleons were detected with an almost 4 pi electromagnetic calorimeter combining the Crystal Ball and TAPS detectors. The data from both targets are of excellent statistical quality and show a narrow structure in the excitation function of gamma n -> n eta. The results from the two measurements are consistent, taking into account the expected effects from nuclear Fermi motion. The best estimates for position and intrinsic width of the structure are W = (1670 +/- 5) MeV and Gamma = (30 +/- 15) MeV. For the first time precise results for the angular dependence of this structure have been extracted.

KW - NEAR-THRESHOLD PHOTOPRODUCTION

KW - COHERENT PHOTOPRODUCTION

KW - EXCLUSIVE MEASUREMENT

KW - RESONANCE REGION

KW - MESONS

KW - DEUTERON

KW - NUCLEON

KW - PROTON

KW - MODEL

U2 - 10.1103/PhysRevLett.111.232001

DO - 10.1103/PhysRevLett.111.232001

M3 - Article

SN - 0031-9007

VL - 111

JO - Physical Review Letters

JF - Physical Review Letters

IS - 23

M1 - 232001

ER -

Narrow Structure in the Excitation Function of eta Photoproduction off the Neutron

Abstract / Description of output

Keywords / Materials (for Non-textual outputs)

Access to Document

Fingerprint

Cite this