Status of glass and bakelite RPC

1
Status of glass and bakelite RPC

• B.Satyanarayana, TIFR, Mumbai
• For INO Collaboration

2
A typical RPC construction
3
RPC R D infrastructure at TIFR
4
Gas mixing and flow control unit
Flow monitor
Gas mixing unit
5
Cosmic telescope and DAQ
6
A few of our preliminary results
7
RPC-S23 noise rate monitoring
8
RPC S-23 efficiency history
9
RPC-S23 streamer size
10
AFM photographs of S-23
Damaged electrode surfaces
Cleaned electrode surfaces
11
Current system and parameters

• Avalanche mode of operation
• R134a 95.5 Iso-Butane 4.5
• Signal strength 2-4mV across 50? load
• External electronic amplification
• BARC-ED pre-amplifiers
• CMS RPC front-ends
• Long term monitoring of efficiency, dark current,
  noise rate, temperature, relative humidity
  (working on pressure monitoring too)

12
CMS RE RPC
Dimensions 730 X 645 X 425 mm
13
CMS S-24 RPCs under test
14
Large area RPC B-3
15
Low noise preamp from ED-BARC
16
Noise rate studies
17
Efficiency studies
18
V-I characteristics of CMS RPC
19
Alumina based gas filter
Gas inlet
Gas outlet
Heating coil
20
Noise rate monitoring of S-25 S-26
21
Efficiency monitoring of S-25 S-26
22
Dark current Vs Temperature
23
Dark current Vs Relative Humidity
24
New gas distribution system
Bubblers
Rotameters
25
New RPC pickup plane
26
CMS Barrel RPC front-end
Kapton cable brings in RPC signals
Handles 16-channels
8-ch FE ASIC
Power CTRL
LVDS Outputs
27
Immediate future plan

• Making more 40cm X 30cm RPCs using Japanese glass
• Using CMS Barrel RPC front-end
• Kapton cable
• New pickup panel
• LVDS to NIM translator module
• Using new gas distribution system