Measurement of the angular distribution in p̄p→ψ(2S) →e+e-

M. Ambrogiani; M. Andreotti; S. Argiro; S. Bagnasco; W. Baldini; D. Bettoni; G. Borreani; A. Buzzo; R. Calabrese; R. Cester; G. Cibinetto; P. Dalpiaz; X. Fan; G. Garzoglio; K. E. Gollwitzer; M. Graham; A. Hahn; M. Hu; S. Jin; D. Joffe; J. Kasper; G. Lasio; M. Lo Vetere; E. Luppi; P. Maas; M. Macrí; M. Mandelkern; F. Marchetto; M. Marinelli; W. Marsh; M. Martini; E. Menichetti; Z. Metreveli; R. Mussa; M. Negrini; M. M. Obertino; M. Pallavicini; N. Pastrone; C. Patrignani; T. K. Pedlar; S. Pordes; E. Robutti; W. Roethel; J. Rosen; P. Rumerio; R. Rusack; A. Santroni; J. Schultz; S. H. Seo; K. K. Seth; G. Stancari; M. Stancari; J. Streets; A. Tomaradze; I. Uman; T. Vidnovic; S. Werkema; G. Zioulas; P. Zweber

doi:10.1016/j.physletb.2005.01.093

Measurement of the angular distribution in p̄p→ψ(2S) →e⁺e^-

M. Ambrogiani, M. Andreotti, S. Argiro, S. Bagnasco, W. Baldini, D. Bettoni, G. Borreani, A. Buzzo, R. Calabrese, R. Cester, G. Cibinetto, P. Dalpiaz, X. Fan, G. Garzoglio, K. E. Gollwitzer, M. Graham, A. Hahn, M. Hu, S. Jin, D. JoffeJ. Kasper, G. Lasio, M. Lo Vetere, E. Luppi, P. Maas, M. Macrí, M. Mandelkern, F. Marchetto, M. Marinelli, W. Marsh, M. Martini, E. Menichetti, Z. Metreveli, R. Mussa, M. Negrini, M. M. Obertino, M. Pallavicini, N. Pastrone, C. Patrignani^*, T. K. Pedlar, S. Pordes, E. Robutti, W. Roethel, J. Rosen, P. Rumerio, R. Rusack, A. Santroni, J. Schultz, S. H. Seo, K. K. Seth, G. Stancari, M. Stancari, J. Streets, A. Tomaradze, I. Uman, T. Vidnovic, S. Werkema, G. Zioulas, P. Zweber

^*Corresponding author for this work

Physics and Astronomy

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

12 Scopus citations

Abstract

We present the first measurement of the angular distribution for the exclusive process p̄p→ψ(2S)→e⁺e^- based on a sample of 6844 events collected by the Fermilab E835 experiment. We find that the angular distribution is well described by the expected functional form dNd/cosθ* ∝1+λcos²θ*, where θ* is the angle between the antiproton and the electron in the center of mass frame, with λ=0.67±0.15(stat)±0.04(sys). The measured value for λ implies a small but non-zero ψ(2S) helicity 0 formation amplitude in p̄p, comparable to what is observed in J/ψ decays to baryon pairs.

Original language	English (US)
Pages (from-to)	177-182
Number of pages	6
Journal	Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume	610
Issue number	3-4
DOIs	https://doi.org/10.1016/j.physletb.2005.01.093
State	Published - Mar 24 2005

Funding

The authors wish to thank the staffs, engineers and technicians at their respective institutions for their valuable help and cooperation. This research was supported by the US Department of Energy and by the Italian Istituto Nazionale di Fisica Nucleare.

ASJC Scopus subject areas

Nuclear and High Energy Physics

Access to Document

10.1016/j.physletb.2005.01.093

Cite this

Ambrogiani, M., Andreotti, M., Argiro, S., Bagnasco, S., Baldini, W., Bettoni, D., Borreani, G., Buzzo, A., Calabrese, R., Cester, R., Cibinetto, G., Dalpiaz, P., Fan, X., Garzoglio, G., Gollwitzer, K. E., Graham, M., Hahn, A., Hu, M., Jin, S., ... Zweber, P. (2005). Measurement of the angular distribution in p̄p→ψ(2S) →e⁺e^-. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 610(3-4), 177-182. https://doi.org/10.1016/j.physletb.2005.01.093

@article{e5feebc9c0f247c4a648629236a13650,

title = "Measurement of the angular distribution in {\=p}p→ψ(2S) →e+e-",

abstract = "We present the first measurement of the angular distribution for the exclusive process {\=p}p→ψ(2S)→e+e- based on a sample of 6844 events collected by the Fermilab E835 experiment. We find that the angular distribution is well described by the expected functional form dNd/cosθ* ∝1+λcos2θ*, where θ* is the angle between the antiproton and the electron in the center of mass frame, with λ=0.67±0.15(stat)±0.04(sys). The measured value for λ implies a small but non-zero ψ(2S) helicity 0 formation amplitude in {\=p}p, comparable to what is observed in J/ψ decays to baryon pairs.",

author = "M. Ambrogiani and M. Andreotti and S. Argiro and S. Bagnasco and W. Baldini and D. Bettoni and G. Borreani and A. Buzzo and R. Calabrese and R. Cester and G. Cibinetto and P. Dalpiaz and X. Fan and G. Garzoglio and Gollwitzer, \{K. E.\} and M. Graham and A. Hahn and M. Hu and S. Jin and D. Joffe and J. Kasper and G. Lasio and \{Lo Vetere\}, M. and E. Luppi and P. Maas and M. Macr{\'i} and M. Mandelkern and F. Marchetto and M. Marinelli and W. Marsh and M. Martini and E. Menichetti and Z. Metreveli and R. Mussa and M. Negrini and Obertino, \{M. M.\} and M. Pallavicini and N. Pastrone and C. Patrignani and Pedlar, \{T. K.\} and S. Pordes and E. Robutti and W. Roethel and J. Rosen and P. Rumerio and R. Rusack and A. Santroni and J. Schultz and Seo, \{S. H.\} and Seth, \{K. K.\} and G. Stancari and M. Stancari and J. Streets and A. Tomaradze and I. Uman and T. Vidnovic and S. Werkema and G. Zioulas and P. Zweber",

note = "Funding Information: The authors wish to thank the staffs, engineers and technicians at their respective institutions for their valuable help and cooperation. This research was supported by the US Department of Energy and by the Italian Istituto Nazionale di Fisica Nucleare.",

year = "2005",

month = mar,

day = "24",

doi = "10.1016/j.physletb.2005.01.093",

language = "English (US)",

volume = "610",

pages = "177--182",

journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",

issn = "0370-2693",

publisher = "Elsevier B.V.",

number = "3-4",

}

Ambrogiani, M, Andreotti, M, Argiro, S, Bagnasco, S, Baldini, W, Bettoni, D, Borreani, G, Buzzo, A, Calabrese, R, Cester, R, Cibinetto, G, Dalpiaz, P, Fan, X, Garzoglio, G, Gollwitzer, KE, Graham, M, Hahn, A, Hu, M, Jin, S, Joffe, D, Kasper, J, Lasio, G, Lo Vetere, M, Luppi, E, Maas, P, Macrí, M, Mandelkern, M, Marchetto, F, Marinelli, M, Marsh, W, Martini, M, Menichetti, E, Metreveli, Z, Mussa, R, Negrini, M, Obertino, MM, Pallavicini, M, Pastrone, N, Patrignani, C, Pedlar, TK, Pordes, S, Robutti, E, Roethel, W, Rosen, J, Rumerio, P, Rusack, R, Santroni, A, Schultz, J, Seo, SH, Seth, KK, Stancari, G, Stancari, M, Streets, J, Tomaradze, A, Uman, I, Vidnovic, T, Werkema, S, Zioulas, G & Zweber, P 2005, 'Measurement of the angular distribution in p̄p→ψ(2S) →e⁺e^-', Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol. 610, no. 3-4, pp. 177-182. https://doi.org/10.1016/j.physletb.2005.01.093

TY - JOUR

T1 - Measurement of the angular distribution in p̄p→ψ(2S) →e+e-

AU - Ambrogiani, M.

AU - Andreotti, M.

AU - Argiro, S.

AU - Bagnasco, S.

AU - Baldini, W.

AU - Bettoni, D.

AU - Borreani, G.

AU - Buzzo, A.

AU - Calabrese, R.

AU - Cester, R.

AU - Cibinetto, G.

AU - Dalpiaz, P.

AU - Fan, X.

AU - Garzoglio, G.

AU - Gollwitzer, K. E.

AU - Graham, M.

AU - Hahn, A.

AU - Hu, M.

AU - Jin, S.

AU - Joffe, D.

AU - Kasper, J.

AU - Lasio, G.

AU - Lo Vetere, M.

AU - Luppi, E.

AU - Maas, P.

AU - Macrí, M.

AU - Mandelkern, M.

AU - Marchetto, F.

AU - Marinelli, M.

AU - Marsh, W.

AU - Martini, M.

AU - Menichetti, E.

AU - Metreveli, Z.

AU - Mussa, R.

AU - Negrini, M.

AU - Obertino, M. M.

AU - Pallavicini, M.

AU - Pastrone, N.

AU - Patrignani, C.

AU - Pedlar, T. K.

AU - Pordes, S.

AU - Robutti, E.

AU - Roethel, W.

AU - Rosen, J.

AU - Rumerio, P.

AU - Rusack, R.

AU - Santroni, A.

AU - Schultz, J.

AU - Seo, S. H.

AU - Seth, K. K.

AU - Stancari, G.

AU - Stancari, M.

AU - Streets, J.

AU - Tomaradze, A.

AU - Uman, I.

AU - Vidnovic, T.

AU - Werkema, S.

AU - Zioulas, G.

AU - Zweber, P.

N1 - Funding Information: The authors wish to thank the staffs, engineers and technicians at their respective institutions for their valuable help and cooperation. This research was supported by the US Department of Energy and by the Italian Istituto Nazionale di Fisica Nucleare.

PY - 2005/3/24

Y1 - 2005/3/24

N2 - We present the first measurement of the angular distribution for the exclusive process p̄p→ψ(2S)→e+e- based on a sample of 6844 events collected by the Fermilab E835 experiment. We find that the angular distribution is well described by the expected functional form dNd/cosθ* ∝1+λcos2θ*, where θ* is the angle between the antiproton and the electron in the center of mass frame, with λ=0.67±0.15(stat)±0.04(sys). The measured value for λ implies a small but non-zero ψ(2S) helicity 0 formation amplitude in p̄p, comparable to what is observed in J/ψ decays to baryon pairs.

AB - We present the first measurement of the angular distribution for the exclusive process p̄p→ψ(2S)→e+e- based on a sample of 6844 events collected by the Fermilab E835 experiment. We find that the angular distribution is well described by the expected functional form dNd/cosθ* ∝1+λcos2θ*, where θ* is the angle between the antiproton and the electron in the center of mass frame, with λ=0.67±0.15(stat)±0.04(sys). The measured value for λ implies a small but non-zero ψ(2S) helicity 0 formation amplitude in p̄p, comparable to what is observed in J/ψ decays to baryon pairs.

UR - http://www.scopus.com/inward/record.url?scp=20044370253&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=20044370253&partnerID=8YFLogxK

U2 - 10.1016/j.physletb.2005.01.093

DO - 10.1016/j.physletb.2005.01.093

M3 - Article

AN - SCOPUS:20044370253

SN - 0370-2693

VL - 610

SP - 177

EP - 182

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

IS - 3-4

ER -