The btev pixel detector and trigger system
This presentation is the property of its rightful owner.
Sponsored Links
1 / 21

The BTeV Pixel Detector and Trigger System PowerPoint PPT Presentation


  • 66 Views
  • Uploaded on
  • Presentation posted in: General

The BTeV Pixel Detector and Trigger System. Simon Kwan Fermilab P.O. Box 500, Batavia, IL 60510, USA BEACH2002, June 29, 2002 Vancouver, Canada. The BTeV Spectrometer. Pixel Vertex Detector. Reasons for Pixel Detector: Superior signal to noise

Download Presentation

The BTeV Pixel Detector and Trigger System

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


The btev pixel detector and trigger system

The BTeV Pixel Detector and Trigger System

Simon Kwan

Fermilab

P.O. Box 500, Batavia, IL 60510, USA

BEACH2002, June 29, 2002

Vancouver, Canada


The btev spectrometer

The BTeV Spectrometer


Pixel vertex detector

Pixel Vertex Detector

  • Reasons for Pixel Detector:

  • Superior signal to noise

  • Excellent spatial resolution -- 5-10 microns depending on angle, etc

  • Very Low occupancy

  • Very fast

  • Radiation hard

  • Special features:

  • It is used directly in the Level 1 trigger

  • Pulse height is measured on every channel with a 3 bit FADC

  • It is inside a dipole and gives a crude standalone momentum


Hybrid silicon pixel devices

HybridSiliconpixeldevices

0.25 mm rad-hard FPIX2 chip

  • Independent development and optimizations of readout chip and sensor

  • n+ pixels on n-type substrates: inter-pixel insulation technology under investigation

  • Bump-bonding of flipped chip: 2 technologies being considered: Indium (In) and solder (SnPb)


The btev pixel detector and trigger system

Comparing to other Pixel Detectors

Luminosity at FermiLab detectors 2x1032cm-2 sec-1

Luminosity at LHC detectors 1x1034cm-2 sec-1


Btev radiation background l 2 10 32 cm 2 s 1 charged hadrons pixels z 55 60 cm

BTeV Radiation Background(L=2·1032 cm-2 s-1), charged hadronsPixels, Z = (55 – 60) cm


Irradiation results pixel roc

Irradiation Results: Pixel ROC


Silicon sensor r d v dep vs fluence

Silicon Sensor R&D:Vdep vs Fluence


High density flex circuit development

High density flex circuit development

  • 15 HDI delivered from CERN; only 4 without defects

  • Preliminary performance assessment very satisfactory  design validation

  • We need to do more extensive tests and find commercial vendor for large scale production


Built 10 model

Built 10% Model


The btev pixel detector and trigger system

The Pixel Detector (2-D Side View)


Physics performance of pixel detector

Physics Performance of Pixel Detector

Primary-secondary vertex separation

Minus generated. s = 138m

Distribution in L/s of

Reconstructed Bs

Mean = 44

t proper (reconstructed) - tproper (generated)

s = 46 fs


The btev level i vertex trigger

Key Points

This is made possible by a vertex detector with excellent spatial resolution, fast readout, low occupancy, and 3-d space points.

A heavily pipelined and parallel processing architecture using inexpensive processing nodes optimized for specific tasks ~ 3000 processors (DSPs).

Sufficient memory (~1 Terabyte) to buffer the event data while calculations are carried out.

The BTeV Level I Vertex Trigger

The trigger will reconstruct every beam crossing and look for TOPOLOGICAL evidence of a B decaying downstream of the primary vertex. Runs at 7.6 MHz!


L1 vertex trigger algorithm

L1 vertex trigger algorithm

  • Generate Level-1 accept if “detached” tracks in the BTeV pixel detector satisfy:

(GeV/c)2

cm

Execute Trigger


L1 trigger efficiencies

L1 trigger efficiencies


Level 2 trigger

Level 2 Trigger

  • Start with the Level 1 tracks from the ``triggering collision” within the crossing.

  • Search for pixel hits along these tracks.

  • Refit the tracks using a Kalman Filter. Resultant momenta are improved to about 5-10%.

  • Resultant event must satisfy one of the two following criteria:

    • A secondary vertex must be present or

    • The collection of tracks must satisfy a minimum pT cut.

  • The combined L1 and L2 rejection is 1000-1.

  • Overall Efficiency is roughly 50% for most B decays of interest.


Summary

Summary

  • Great progress has been achieved in the design of the sensor, front end electronics and module structure of the BTeV pixel detector

  • We are making rapid progress towards a full system design that satisfies all the BTeV requirements

  • This vertex system will be the key element of the Trigger algorithm that will enable efficient collection of a variety of beauty decays & provide a superb tool to challenge the Standard Model


  • Login