Thin pixel development for the SuperB silicon vertex tracker Rizzo, G.; Avanzini, C.; Batignani, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2011, Letnik:
650, Številka:
1
Journal Article
Recenzirano
The high luminosity SuperB asymmetric
e
+
e
−
collider, to be built near the INFN National Frascati Laboratory in Italy, has been designed to deliver a luminosity greater than 10
36
cm
−2
s
−1 with ...moderate beam currents and a reduced center of mass boost with respect to earlier B-Factories. An improved vertex resolution is required for precise time-dependent measurements and the SuperB Silicon Vertex Tracker will be equipped with an innermost layer of small radius (about 1.5
cm), resolution of
10
–
15
μ
m
in both coordinates, low material budget (
<
1
%
X0), and able to withstand a background rate of several tens of MHz/cm
2. The ambitious goal of designing a thin pixel device with these stringent requirements is being pursued with specific R&D programs on different technologies: hybrid pixels, CMOS MAPS and pixel sensors developed with vertical integration technology. The latest results on the various pixel options for the SuperB SVT will be presented.
Con el objetivo de disminuir el endurecimiento del producto se estudió la influencia de la temperatura y tiempo de l proceso de secado en las propiedades organolépticas de bocaditos salados, ...nutricionalmente e quilibrados, a base de amaranto popeado, expuestos a 100 ºC - 14 minutos , hume dad 14,7% base seca y actividad acuosa 0,593 . De las curvas experimentales de secado s e seleccionaron nuevas condi ciones operativas, a humedad constante , resultando : 70 ºC - 17 minutos y 80 ºC - 16 minutos. La influencia de estas variables en el producto s e evaluó organoléptic amente por una p rue ba de diferencia con un control midiendo el descriptor dureza como parámetro de calidad, contrastándolo por método instrumental con un texturómetro. N o se evidenció diferencia significativa entre las muestras de 100ºC - 14 minutos y 80 ºC - 16 minutos, pero si para la muestra 70 ºC - 17 minutos. Se concluye que en las condiciones estudiadas las variables temperatura y tiempo influyen en las características organolépticas de lo s bocaditos.
We present results of a search for CP violation in B0B0bar mixing with the BABAR detector. We select a sample of B0-->D*-Xl+ nu decays with a partial reconstruction method and use kaon tagging to ...assess the flavor of the other B meson in the event. We determine the CP violating asymmetry ACP = (N(B0B0) - N(B0bar B0bar))/(N(B0B0) + N(B0bar B0bar))=(0.06+-0.17+0.38-0.32)%, corresponding to delta_CP =1 - |q/p| =(0.29+-0.84+1.88 -1.61)*10^-3.
Beam test results for the SuperB-SVT thin striplet detector Fabbri, L.; Comotti, D.; Manghisoni, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2013, Letnik:
718
Journal Article
Recenzirano
Odprti dostop
The baseline detector option for the first layer of the SuperB Silicon Vertex Tracker (SVT) is a high resistivity double-sided silicon device with short strips (striplets) at 45° angle to the ...detector's edge. A prototype was tested with a 120GeV/c pion beam in September 2011 at the SPS-H6 test-beam line at CERN. In this paper studies on efficiency, resolution and cluster size are reported.
En este trabajo se estima experimentalmente los coeficientes de difusión efectivos de agua en semillas de amaranto rehumectadas para posteriores estudios del rendimiento y calidad del popeado o ...reventado del grano. Las semillas se rehumectaron por inmersión en agua a temperaturas de 11, 35 y 50 °C durante intervalos de tiempo de 0.5, 1, 2 y 4 h, determinándose gravimétricamente la humedad adquirida en cada condición estudiada. Para estimar el coeficiente de difusión se empleó el modelo difusional basado en la solución analítica de la segunda ley de Fick, considerando a la semilla de amaranto como una esfera de radio 0.6 mm. Se midieron las humedades de equilibrio en las condiciones estudiadas luego de un tiempo de 24 h de rehumectación. Los resultados obtenidos fueron similares a los encontrados por otros autores para semillas de quinua y otras variedades de amaranto, con características semejantes. Los valores de los coeficientes de difusión efectivos aumentaron con el incremento de la temperatura.
The photon spectrum in the inclusive electromagnetic radiative decays of the $B$ meson, $B \to X_{s} \gamma$ plus $B \to X_{d} \gamma$, is studied using a data sample of $(382.8 \pm 4.2) \times 10^6$ ...$\Upsilon(4S) \to B\overli\ ne{B}$ decays collected by the \babar\ experiment at SLAC. The spectrum is used to extract the branching fraction ${\cal B}(B \to X_{s} \gamma)=(3.21 \pm 0.33)\times 10^{-4}$ for $E_{\gamma}>1.8 \gev$ and the direct CP asymmetry $A_{CP}(B \to X_{s+d} \gamma)=0.057 \pm 0.063$. The effects of detector resolution and Doppler smearing are unfolded to measure the photon energy spectrum in the $B$ meson rest frame.
The superB silicon vertex tracker Rizzo, G.; Avanzini, C.; Batignani, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The SuperB asymmetric
e
+
–
e
-
collider has been designed to deliver a luminosity greater than
10
36
cm
-
2
s
-
1
with moderate beam currents. Comparing to current B-Factories, the reduced center of ...mass boost of the SuperB machine requires improved vertex resolution to allow precision measurements sensitive to New Physics. We present the conceptual design of the silicon vertex tracker (SVT) for the SuperB detector with the present status of the R&D on the different options under study for its innermost Layer0.
A 4096-pixel MAPS device with on-chip data sparsification Gabrielli, A.; Batignani, G.; Bettarini, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2009, Letnik:
604, Številka:
1
Journal Article
Recenzirano
A prototype of a mixed-mode ASIC composed of a fast readout architecture that interfaces with a matrix of 4096 Monolithic Active Pixel Sensor (MAPS) was fabricated via STM 130
nm CMOS technology. ...Groups of 4×4 pixels form a macro-pixel (MP). The readout architecture is parallel and could overcome the readout speed limit of big matrices. As the output port can only accept one-hit information at a time, an internal queuing system has been provided to face high hit-rate conditions. The ASIC can work in two different manners as it can be connected to an actual full-custom matrix of MAPS or to a digital matrix emulator composed of standard cells, for testing facilities. For both operating modes a slow-control phase is required to load the chip configuration. Previous versions of similar ASICs were designed and tested. The work is aimed at improving the design of MAPS detectors with an on-chip fast sparsification system, for particle tracking, to match the requirements of future high-energy physics experiments. The readout architecture implemented is data driven extending the flexibility of the system to be also used in first level triggers on tracks in vertex detectors. Preliminary simulations and tests indicate that the readout system can cope with an average hit-rate up to 100
MHz/cm
2 if a master clock of 80
MHz is used, while maintaining an overall efficiency over 99%.
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