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Selen, M.

Publications and source records attributed to Selen, M..

Status of the Dark Energy Survey Camera (DECam) project

The Dark Energy Survey Collaboration has completed construction of the Dark Energy Camera (DECam), a 3 square degree, 570 Megapixel CCD camera which will be mounted on the Blanco 4-meter telescope at CTIO. DECam will be used to perform the 5000 sq. deg. Dark Energy Survey with 30% of the telescope time over a 5 year period. During the remainder of the time, and after the survey, DECam will be available as a community instrument. All components of DECam have been shipped to Chile and post-shipping checkout finished in Jan. 2012. Installation is in progress. A summary of lessons learned and an update of the performance of DECam and the status of the DECam installation and commissioning will be presented.

79 ASTRONOMY AND ASTROPHYSICS↗

Amplitude analyses of the decays χ c1 →ηπ⁺π⁻ and χ c1 →η'π⁺π⁻

Using a data sample of 2.59×10⁷ ψ(2S) decays obtained with the CLEO-c detector, we perform amplitude analyses of the complementary decay chains ψ(2S)→γχ c1 ; χ c1 →ηπ⁺π⁻ and ψ(2S)→γχ c1 ; χ c1 →η'π⁺π⁻. We find evidence for an exotic P-wave η'π amplitude, which, if interpreted as a resonance, would have parameters consistent with the π₁(1600) state reported in other production mechanisms. We also make the first observation of the decay a₀(980)→η'π and measure the ratio of branching fractions B(a₀(980)→η'π)/B(a₀(980)→ηπ)=0.064±0.014±0.014. The ππ spectrum produced with a recoiling η is compared to that with η' recoil.

Adams, G. S.↗

Studies of D⁺→{η',η,Φ}e⁺ν e

We report the first observation of the decay D⁺→η'e⁺ν e in two analyses, which combined provide a branching fraction of B(D⁺→η'e⁺ν e )=(2.16±0.53±0.07)×10⁻⁴. We also provide an improved measurement of B(D⁺→ηe⁺ν e )=(11.4±0.9±0.4)×10⁻⁴, provide the first form factor measurement, and set the improved upper limit B(D⁺→Φe⁺ν e )<0.9×10⁻⁴ (90%C.L.).

Yelton, J.↗