Absorption of the ω and ϕ mesons in nuclei.
Because of their long lifetimes, the ω and ϕ mesons are the ideal candidates for the study of possible modifications of the in-medium meson-nucleon interaction through their absorption inside the nucleus. During the E01-112 experiment at the Thomas Jefferson National Accelerator Facility, the mesons were photoproduced from 2H, C, Ti, Fe, and Pb targets. This Letter reports the first measurement of the ratio of nuclear transparencies for the e+e- channel. The ratios indicate larger in-medium widths compared with what have been reported in other reaction channels. The absorption of the ω meson is stronger than that reported by the CBELSA-TAPS experiment and cannot be explained by recent theoretical models.
Wood
M H
MH
Canisius College, Buffalo, New York 14208, USA.
Nasseripour
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Paolone
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Djalali
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Weygand
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Adhikari
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Anghinolfi
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Ball
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Battaglieri
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Batourine
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Bedlinskiy
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Bellis
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Berman
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Biselli
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Branford
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Briscoe
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Brooks
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Burkert
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Careccia
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Carman
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Cole
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Collins
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Crede
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D'Angelo
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Daniel
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A
De Vita
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De Sanctis
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Deur
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Dey
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Dhamija
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Dickson
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Doughty
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Dupre
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R
Egiyan
H
H
El Alaoui
A
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El Fassi
L
L
Eugenio
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Fegan
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Gabrielyan
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Garçon
M
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Gilfoyle
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Giovanetti
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Girod
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Goetz
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Gohn
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Gothe
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Graham
L
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Guidal
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M
Guo
L
L
Hafidi
K
K
Hakobyan
H
H
Hanretty
C
C
Hassall
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Hicks
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Holtrop
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M
Ilieva
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Ireland
D G
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Ishkhanov
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Jawalkar
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Jo
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Joo
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Keller
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Khandaker
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Khetarpal
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Kim
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Kim
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Klein
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Klein
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FJ
Konczykowski
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Kubarovsky
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Kuleshov
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Kuznetsov
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Livingston
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Martinez
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Mayer
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McAndrew
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McCracken
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McKinnon
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Meyer
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Mineeva
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Mirazita
M
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Mokeev
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Moreno
B
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Moriya
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Morrison
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Munevar
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Nadel-Turonski
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Ni
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Niccolai
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Niculescu
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Niculescu
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Niroula
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Osipenko
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Ostrovidov
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Paremuzyan
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Park
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Park
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Pasyuk
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Anefalos Pereira
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Pisano
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Pogorelko
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Pozdniakov
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Price
J W
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Procureur
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Prok
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Protopopescu
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Raue
B A
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Ricco
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Ripani
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Rosner
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Rossi
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Sabatié
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Saini
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Salamanca
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Salgado
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Schott
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Schumacher
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Seder
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Seraydaryan
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Sharabian
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Smith
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Sober
D I
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Sokhan
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Stepanyan
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Stepanyan
S S
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Stoler
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Strakovsky
I I
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Strauch
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Taiuti
M
M
Tang
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Taylor
C E
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Tedeschi
D J
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Tkachenko
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Ungaro
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Vernarsky
B
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Vineyard
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Voutier
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Watts
D P
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Weinstein
L B
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Zhang
J
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Zhao
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Zhao
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