For the Phase-II Upgrade of the ATLAS Detector 1, its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100% silicon ...tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-250) 2,2 and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests.
Here, we study the processes e+e– → π+π–π0π0π0γ and π+π–π0π0ηγ in which an energetic photon is radiated from the initial state. The data are collected with the BABAR detector at SLAC. About 14 000 ...and 4700 events, respectively, are selected from a data sample corresponding to an integrated luminosity of 469 fb–1. The invariant mass of the hadronic final state defines the effective e+e– center-of-mass energy. From the mass spectra, the first precise measurement of the e+e– → π+π–π0π0π0 cross section and the first measurement ever of the e+e– → π+π–π0π0η cross section are performed. The center-of-mass energies range from threshold to 4.35 GeV. The systematic uncertainty is typically between 10% and 13%. The contributions from ωπ0π0, ηπ+π–, and other intermediate states are presented. We observe the J/ψ and ψ(2S) in most of these final states and measure the corresponding branching fractions, many of them for the first time.
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This paper describes the course of follicular development in vivo in the marmoset monkey, the only anthropoid primate with
a relatively high (2-4) and variable ovulation number. Results are presented ...in relation to predictions from a mathematical
model of control of follicle selection and ovulation number. Repeated laparoscopic examinations during the follicular phase
were conducted for 14 cycles. Ovulatory follicles were 1.0 mm (median) in diameter at Day 6 and could be distinguished from
nonovulatory follicles by Day 8, at which point they were 2.0 mm in diameter. Ovulations were not synchronous; the most common
observation 1-2 days after the estradiol peak was ovulation of one follicle but not the other. Examination of the course of
follicular development within a cycle and the distribution of ovulation sites both supported predictions stemming from a mathematical
model of follicle selection developed by Lacker et al. Biol Reprod 1987; 37:570-580. Specific findings were the following:
1) Variations in patterns of follicle growth within a cycle resembled those generated by the model; in 64% of cycles, the
2-3 ovulatory follicles grew at similar rates. However, in 36% of cycles, ovulatory follicles displayed disparate rates of
growth. 2) An examination of the distribution of ovulation sites (right versus left) revealed no significant difference from
a binomial distribution, suggesting the likelihood that interovarian (rather than intraovarian) factors control this distribution.
The decay τ-→K-KSντ has been studied using 430×106 e+e-→τ+τ- events produced at a center-of-mass energy around 10.6 GeV at the PEP-II collider and studied with the BABAR detector. The mass spectrum ...of the K-KS system has been measured and the spectral function has been obtained. The measured branching fraction B(τ-→K-KSντ)=(0.739±0.011(stat)±0.020(syst))×10-3 is found to be in agreement with earlier measurements.
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The DIRC particle identification system for the BaBar experiment Aleksan, R.; Amerman, L.; Aston, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2005, Volume:
538, Issue:
1-3
Journal Article
Peer reviewed
Open access
A new type of ring-imaging Cherenkov detector is being used for hadronic particle identification in the BABAR experiment at the SLAC B Factory (PEP-II). This detector is called DIRC, an acronym for ...Detection of Internally Reflected Cherenkov (Light). This paper will discuss the construction, operation and performance of the BABAR DIRC in detail.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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