The BaBar Silicon Vertex Tracker is a five layers, double sided AC-coupled silicon microstrip detector operating on the PEP-II storage ring at the Stanford Linear Accelerator Center. The performance ...of the SVT after 4 years of running is described. Results from radiation hardness tests are presented and the implications of the absorbed radiation dose on the SVT lifetime are discussed.
The silicon vertex tracker (SVT) of the BaBar experiment at PEP-II is described. This is the crucial device for the measurement of the B meson decay vertices to extract charge-conjugation parity (CP) ...asymmetries. It consists of five layers of double-sided ac-coupled silicon strip detectors, read out by a full-custom integrated circuit, capable of simultaneous acquisition, digitization, and transmission of data. It represents the core of the BaBar tracking system, providing position measurements with a precision of 10 /spl mu/m (inner layers) and 30 /spl mu/m (outer layers). The relevant performances of the SVT are presented, and the experience acquired during the construction, installation, and the first five years of data-taking is described. Innovative solutions are highlighted, like the sophisticated alignment procedure, imposed by the design of the silicon tracker, integrated in the beamline elements and mechanically separated from the other parts of BaBar. The harshness of the background conditions in the interaction region required several studies on the radiation damage of the sensors and the front-end chips, whose results are presented. Over the next five years the luminosity is predicted to increase by a factor three, leading to radiation and occupancy levels significantly exceeding the detector design. Extrapolation of future radiation doses and occupancies is shown together with the expected detector performance and lifetime. Upgrade scenarios to deal with the increased luminosity and backgrounds are discussed.
Radiation damage studies for the B aB ar Silicon Vertex Tracker Re, V.; Kirkby, D.; Bruinsma, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2005, Letnik:
549, Številka:
1
Journal Article
Recenzirano
The Silicon Vertex Tracker of the
B
aB
ar
experiment is a five-layer, double-sided AC-coupled silicon microstrip detector operating on the PEP-II storage ring at the Stanford Linear Accelerator ...Center. After more than four years of running, the silicon sensors and the front-end electronics in the inner layer have absorbed radiation doses up to 2
Mrad. In this paper we present results from radiation hardness tests and discuss the implications of the absorbed radiation dose on the Silicon Vertex Tracker lifetime.
The DIRC particle identification system for the B aB ar experiment Adam, I.; Aleksan, R.; Amerman, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2005, Letnik:
538, Številka:
1
Journal Article
Recenzirano
A new type of ring-imaging Cherenkov detector is being used for hadronic particle identification in the B
aB
ar 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 B
aB
ar DIRC in detail.
The BABAR silicon vertex tracker (SVT) has been in operation for four years at the PEP-II electron-positron storage ring. During this time the SVT modules have accumulated a radiation dose up to 2 ...Mrad. We study the degradation in the performance of the SVT due to this accumulated dose which is highly non uniform across the device and also within the individual silicon detectors. To extrapolate the performance of the device to the future we study separately the effect of the irradiation on silicon detectors, front end integrated circuits and on a complete detector module under controlled radiation conditions, using a /sup 60/Co source and a 0.9 GeV e/sup -/ beam. We compare the results to the data from the SVT. In particular we show the dependence of the charge collection efficiency on the radiation dose even when a small stripe of the module is irradiated up to space charge sign inversion. Since the modules that are located in the plane of the beams will suffer significant radiation damage, we will describe our plans for their replacement in 2005 and for the operation of the SVT through the lifetime of the BABAR experiment.
Status and future plans of the BABAR Silicon Vertex Tracker Re, V.; Kirkby, D.; Berryhill, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2003, Letnik:
511, Številka:
1
Journal Article
Recenzirano
A brief summary of the design goals, description, and performance of the
BABAR Silicon Vertex Tracker is given. Results from radiation hardness tests are discussed, which indicate satisfactory ...operation up to
5
Mrad
of accumulated radiation. The local alignment procedure has made significant improvements recently, and four readout sections were recovered during the
BABAR shutdown in 2002.
Radiation hardness and monitoring of the B aB ar vertex tracker Re, V.; Bruinsma, M.; Kirkby, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2004, Letnik:
518, Številka:
1
Journal Article
Recenzirano
The Silicon Vertex Tracker (SVT) is an essential component of the B
aB
ar experiment at the PEP-II asymmetric B factory. The SVT has performed very well and several radiation studies have been ...carried out to determine that it will continue do so up to integrated radiation doses of
5
Mrad
. The SVT radiation monitoring and protection system consists of silicon PIN-diodes, which are suffering from radiation damage, reducing their precision. Diamond sensors are highly resistant to radiation damage and the possibility of replacing the PIN-diodes with diamonds is currently under investigation. Two polycrystalline diamonds have been installed near the B
aB
ar interaction region and show promising results when compared to the PIN-diodes.
The Silicon Vertex Tracker (SVT) of the B
aB
ar experiment at the PEP-II asymmetric B factory is a crucial element of the B
aB
ar physics program. The SVT is a five layer device with double-sided ...silicon strip detectors and a custom readout chip based on a time-over-threshold circuit. The SVT is fully operational since the installation in the experiment in 1999. We briefly review the detector performance after more than 3 years of data taking in factory mode. The high-luminosity running of PEP-II through the end of the decade will increase the radiation level in the SVT above its design limit. Radiation issues will be reviewed and results from radiation tests of the various detector components will be presented. We finally discuss the outlook for the long-term running of the SVT.
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