Commissioning TileCal with Cosmic Ray Muons

J. PilcherUniversity of Chicago

6/24/03 J. Pilcher 2

TileCal Assembly Schedule Surface preassembly of barrel

Complete preassembly December ’03 Start disassembly late February ’04 ~2 months possible for commissioning studies

Cs studies over full height of barrel Cosmic ray muons through full readout system

Underground assembly of barrel Begin 11 May ’04 Module assembly complete 10 Sept. ’04 Services complete 26 Nov. ’04 Tests and commissioning 29 Nov. ’04 - 27 Dec. ’04

Short time (4 weeks) Unpopular time for working We must be efficient and well prepared

6/24/03 J. Pilcher 3

Commissioning Preassembly

Goals System tests with more modules

Largest system run to date is 6 superdrawers– In test beam

Full barrel contains 128 superdrawers Intermediate step is essential

System tests with hardware not yet used LV power supply sets in fingers Bulk LV power source 80m away LVL1 trigger hardware interfacing to TileCal

– Patch panels to remap tower and muon signals

– Receiver boards Hardware RODs

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Commissioning in Pit

Check that all systems are alive in Dec. ’04 Cs and CIS runs Thorough check-out with “physics” signals will take

longer Attractive to run system on cosmics periodically

from Dec. ’04 - Dec. ’06 Monitor stability Get all bugs ironed out Provide trigger to other parts of ATLAS Likely very little access to pit during this time

Most work in USA15

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Estimate Trigger Rates

Consider rate in back-to-back trigger towers (16 + 16 equipped modules)

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Estimate Trigger Rates

These triggers are the most useful Muon fully traverses single towers Could also select these muons with bottom

section of cal. and scintillator in “beam” region Rate is lower than trigger using larger

towers (eg. 0.4 x 0.4) Return to this case later

Do simple calculation with Excel

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Cosmic Ray Flux

Use numbers from Particle Data Group Tabulate in Excel

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Cosmic Ray Flux

Integrate over muon energy above a threshold Must impose range cut-off, depending on (or )

Set up table for linear interpolation Gives muons / sec / m**2 / steradian

Muon Flux vs Energy (PDG, Sec. 23.3)

E_mu dN_mu/dE dN_mu Integral dI/dE(GeV) (s-m**2-sr/GeV)(s-m**2-sr)

1.5 20.747 16.271 56.0442.5 11.795 9.633 39.773 -9.633.5 7.472 6.407 30.140 -6.414.5 5.342 4.475 23.733 -4.485.5 3.608 3.177 19.258 -3.186.5 2.745 2.479 16.081 -2.487.5 2.213 1.957 13.602 -1.968.5 1.702 1.550 11.645 -1.559.5 1.398 5.166 10.095 -0.9415 0.481 1.824 4.929 -0.3620 0.249 0.979 3.105 -0.2025 0.143 0.583 2.126 -0.1230 0.090 0.375 1.543 -0.0835 0.060 0.252 1.168 -0.0540 0.041 0.176 0.916 -0.0445 0.029 0.127 0.740 -0.0350 0.022 0.095 0.613 -0.0255 0.016 0.073 0.517 -0.0160 0.013 0.058 0.444 -0.0165 0.010 0.046 0.387 -0.0170 0.008 0.038 0.340 -0.0175 0.007 0.031 0.302 -0.0180 0.006 0.026 0.271 -0.0185 0.005 0.021 0.245 0.0090 0.004 0.018 0.224 0.0095 0.003 0.015 0.206 0.00

100 0.003 0.159 0.191 0.00200 0.000 0.021 0.032 0.00300 0.000 0.006 0.011 0.00400 0.000 0.002 0.005 0.00500 0.000 0.001 0.003 0.00600 0.000 0.001 0.002 0.00700 0.000 0.000 0.001 0.00800 0.000 0.000 0.001 0.00900 0.000 0.000 0.000 0.00

1000 0.000 0.000 0.000 0.00

6/24/03 J. Pilcher 9

Cosmic Ray Flux

Range information Use PDG, Sec. 26, Ref. 1 for range-energy & dE/dx

Article by D.E. Groom et al., Nucl. Data Tables 78, for muons in iron

Set up table for linear interpolation Use module geometry from CDD drawings

Solid steel at inner and outer radii (including girder, etc.) Steel and scintillator mixture between

Muon range in iron

Range dE/dx T_mu(gm/cm^2) (MeV/gm) (GeV)

640.2 1.582 1.000888.5 1.637 1.4001248 1.697 2.0001825 1.767 3.000 *2383 1.816 4.000 *4509 1.936 8.000 *

* Rows of interest

6/24/03 J. Pilcher 10

Rate Calculation

Muon Rate on Surface (integrated over 16 phi wedges)

Cell Eta Max Theta Delta Delta L_eff A_proj d_omega dA*domeg L_material E_cutoff RateMax Min Average Theta Z all phi(rad) (rad) (rad) (rad) (mm) (mm) (mm**2) (sr) (m**2-sr) (gm/cm**2) (GeV) (per min)

A1 0.1 1.571 1.471 1.52 0.0998 245 4906 57857 0.00240 1.39E-04 2305 3.95 5.9A2 0.2 1.471 1.372 1.42 0.0988 248 4955 57858 0.00236 1.36E-04 2328 3.99 5.7A3 0.3 1.372 1.275 1.32 0.0969 253 5054 57861 0.00227 1.31E-04 2374 4.08 5.1A4 0.4 1.275 1.181 1.23 0.0941 260 5202 57865 0.00214 1.24E-04 2444 4.22 4.4A5 0.5 1.181 1.090 1.14 0.0906 270 5403 57869 0.00198 1.15E-04 2539 4.39 3.6A6 0.6 1.090 1.004 1.05 0.0866 283 5658 57874 0.00181 1.05E-04 2658 4.61 2.9A7 0.7 1.004 0.922 0.96 0.0820 299 5970 57880 0.00162 9.40E-05 2613 4.52 2.4A8 0.8 0.922 0.845 0.88 0.0772 317 6341 57885 0.00144 8.33E-05 2235 3.83 2.2

TOTAL 32.2 per min.1930 per hr.

Consider back-to-back cells Area from plane mid-way through

A-cell on bottom Solid angle from corresponding

plane on top Scale rate by cos2 (zenith angle) Integrate over wedges in

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Rate Variation with and

Plot fraction of total rate versus and Easy to scale rate to smaller configurations

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Rate Estimate in UX15 Pit

PX16

(10 m Inner Dia.)

PX14

(14 m Inner Dia.)

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Rate Estimate in UX15 Pit

Overburden corresponds to 55 m of rock with density 2.4 gm/cm**3

Range cut-off now 34 GeV instead of 4 GeV Based on CERN Yellow Report 71-18

SPS study of range-energy and dE/dx of high energy muons

Expected rate reduction is factor of ~22 Zenith angle dependence of overburden not included

Would give ~10% reduction Vertical access shafts not included

Would increase rates for certain and Expected rate ~90/hr

Rob McPherson has been asked for a more detailed GEANT-based estimate

6/24/03 J. Pilcher 14

Rate with Alternative Trigger

Consider trigger on towers of (0.4 x 0.4) Same area as before but solid angle increased

by 16 Rate increased by ~16 32K events/hr on surface (was 1.9K/hr) 1.5K events/hr in pit (was 0.09K/hr)

Energy spread over several towers Trigger less clean Events less useful for calorimeter diagnostics

Much less trigger hardware needed Could filter events at LVL2

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Comments on Rates

There is a very useful trigger rate both on the surface and in the pit

Actual rate on surface next winter will depend on how much electronics is available

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Hardware Needed Electronics drawers (64) - probably OK LV power in fingers Bulk LV power (200V for USA15) Cabling and fibers TTC hardware LVL1 trigger interface hardware

Patch panels to separate tower and muon signals Receiver boards (64 towers each) Trigger logic for cosmic ray running

LVL2 hardware ROD modules ROD crate and controller Output hardware from ROD crate (Ethernet?)

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LV System

BULKSUPPLY

3 X 240 VAC

200 V dc

200 V dc

200 V dc

USA 15

splitter box

splitter box

splitter box

200V Power

ELMBAUX SUPPLY

USA 15

splitter box

AUX SUPPLY

INTERLOCK

Monitoring

CAN BUS cable

200 meters

120 ohmtermination

Rt

Rt

PCIcancard

1.5 - 2 metercable

USA15

Control

LV supplies to Patch Panel

Set of 8 DC to DC convertersWith monitoring and control in each finger

6/24/03 J. Pilcher 18

LV System

Need full scale prototype for 2 fingers with 200V bulk supply, cables, splitter boxes This summer?

Need preproduction units Use in preassembly commissioning next

winter 64 of 256 fingers? 32 of 256? looks reasonable

Feasibility????

6/24/03 J. Pilcher 19

LVL1 Interface Hardware

Cable from barrel drawer delivers 9 tower signals and 7 muon signals Splitter box needed to

collect tower and muon signals on separate cables

Group tower signals as needed for LVL1 receiver boards

Whose responsibility???

Drawing shows required organization for 16+16 drawers

6/24/03 J. Pilcher 20

LVL1 Interface Hardware

Receiver boards produced a single-ended, conditioned, analog signal for each tower Will go to flash ADC boards in ATLAS Could be used for cosmic trigger instead

Trigger on towers of 0.4 x 0.4 for 8+8 modules requires the following

– add analog signals in groups of 16 towers (0.1x0.1 to 0.4x0.4)

– Require energy threshold on sum (discriminate)

– Take 8 2-fold coincidences between back-to-back towers

– Take OR of the 8 coincidence outputs

6/24/03 J. Pilcher 21

LVL2 Hardware

Data from drawer goes to ROD modules 1 module handles 8 drawers 8+8 modules 32 drawers or 4 RODs Needs ROD crate and ROD Crate Controller

Might log data from RCC over Ethernet– Done for other systems in test beam

ROD schedule? 2 prototype modules planned for September

Can we get 4? Production not until next spring

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Conclusions

Commissioning with muons is attractive and necessary The trigger rates look fine

Try this week to agree on target configuration for next winter Confirm responsibilities and explore timetable with

TDAQ groups Over next few weeks make more precise list of

items needed and identify items requiring more help

People willing to help might meet in July to agree on division of tasks (phone + video + face-to-face)