Transcript PMD (Photon Multiplicity Detector)

STAR
PMD
Brookhaven National Laboratory
Charles Udanoh
Mentor:Dr. Jim Thomas
What is you assignment?
Working with Mr. Tapan Naik
Conducting tests with students
Searching for Disoriented Chiral
Condensates (DCC)
Why search for DCC?
To generate valuable information on
vacuum structure of the strong
interaction
And the nature of the chiral phase
transition
Past Experiments (WA98 and
ALICE)
Used PMD,SPMD and Plastic ball
detectors to
- look for collective flow of photons and
charged particles (like pions and
protons)
- to estimate the percentage of the
elliptic flow depending upon the
centrality
What is Photons Multiplicity
Detector ( PMD)?
The PMD is a Pre-shower photon Detector
suitable for counting photons in highenergy nucleus - nucleus collisions.
PMD Cont.
•It Measures multiplicity and spatial
distribution of photons on an event-byevent basis in high energy ion
experiments.
•It study’s Deconfinement transitions,
Chiral symmetry restoration and matter
under extreme conditions
Mechanical design of PMD
The honeycomb chambers are fabricated in
the form of unit modules, which can be
handled conveniently.
The unit module consists of a rhombus of
side approx. 260 mm containing a matrix of
24 x 24 cells.
This shape has identical boundaries on all
four sides. The wall thickness at the
boundaries is half of that of the inner walls.
Control System
The control system consist of three distinct subsystems:
THE END