Detection of high-energy gamma-ray emission from the globular cluster 47 Tucanae with Fermi.
We report the detection of gamma-ray emissions above 200 megaelectron volts at a significance level of 17sigma from the globular cluster 47 Tucanae, using data obtained with the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. Globular clusters are expected to emit gamma rays because of the large populations of millisecond pulsars that they contain. The spectral shape of 47 Tucanae is consistent with gamma-ray emission from a population of millisecond pulsars. The observed gamma-ray luminosity implies an upper limit of 60 millisecond pulsars present in 47 Tucanae.
Abdo
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Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA.
Ackermann
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Ajello
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Atwood
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Axelsson
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Baldini
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Ballet
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Barbiellini
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Bastieri
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Baughman
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Bechtol
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Bellazzini
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Berenji
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Blandford
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Bloom
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Bonamente
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Borgland
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Bregeon
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Brez
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Brigida
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Bruel
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Burnett
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Caliandro
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Cameron
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Caraveo
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Casandjian
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Cecchi
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Celik
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Charles
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Chaty
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Chekhtman
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Cheung
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Chiang
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Ciprini
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Claus
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Cohen-Tanugi
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Conrad
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Cutini
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Dermer
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de Palma
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Digel
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Dormody
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do Couto e Silva
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Drell
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Dubois
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Dumora
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Farnier
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Favuzzi
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Fegan
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Focke
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Frailis
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Fukazawa
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Fusco
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Gargano
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Gasparrini
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Gehrels
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Germani
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Giebels
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Giglietto
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Giordano
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Glanzman
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Godfrey
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Grenier
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Grove
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Guillemot
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Guiriec
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Hanabata
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Harding
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Hayashida
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Hays
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Horan
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Hughes
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Jóhannesson
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Johnson
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Johnson
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Johnson
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Johnson
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Kamae
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Katagiri
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Kawai
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Kerr
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Knödlseder
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Kuehn
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Kuss
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Lande
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Latronico
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Lemoine-Goumard
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Longo
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Loparco
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Lott
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Lovellette
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Lubrano
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Makeev
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Mazziotta
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McConville
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McEnery
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Meurer
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Michelson
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Mitthumsiri
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Mizuno
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Moiseev
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Monte
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Monzani
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Morselli
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Moskalenko
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Murgia
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Nolan
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Norris
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Nuss
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Ohsugi
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Omodei
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Orlando
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Ormes
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Paneque
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Panetta
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Parent
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Pelassa
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Pepe
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Pierbattista
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Piron
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Porter
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Rainò
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Rando
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Razzano
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Rea
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Reimer
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Reimer
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Reposeur
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Ritz
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Rochester
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Rodriguez
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Romani
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Roth
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Ryde
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Sadrozinski
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Sanchez
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Sander
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Saz Parkinson
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Sgrò
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Smith
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Smith
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Spandre
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Spinelli
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Starck
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Strickman
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Suson
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Tajima
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Takahashi
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Tanaka
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Thayer
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Thayer
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Thompson
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Tibaldo
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Torres
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Tosti
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Tramacere
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Uchiyama
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Usher
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Vasileiou
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Vilchez
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Vitale
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Wang
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Webb
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Winer
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Wood
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Ylinen
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Ziegler
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