# Presentation: 482583

## ILC Instrumentation R&D at Fermilab:

**ILC Instrumentation R&D at Fermilab:**
**NML Test Accelerator & A0-Photoinjector**Manfred Wendt*Fermi National Accelerator Laboratory, Batavia, IL 60510, U.S.A.*

**Recycling of A0-Photoinjector Beam Instruments for NML**

**Waveguide-loaded pillbox with slot coupling.**
**Dimensioning for f****010**** and f****110**** symmetric to f****RF****: **-** **fRF = 1.3 GHz, - f010 ≈ 1.1 GHz, - f110 ≈ 1.5 GHz.
**Dipole- and monopole ports, no reference cavity for intensity signal normalization and signal phase (sign).**
**Q****load**** ≈ 600 (~ 10 % cross-talk at 300 ns bunch-to-bunch spacing).**
**Minimization of the X-Y cross-talk (dimple tuning).**
**Simple (cleanable) mechanics.**
**Iteration of EM-simulations for optimizing all dimensions.**

_**Goal:**_** **
- Development of a**cold CM-free L-Band cavity BPM **with < 1 μm single bunch resolution

- RF-gun

- booster cavities1 & 2

- 3.9 Ghz cav

- doublet

- triplet

- quads

- beam
- trans.

- bunch compressor

- dipole

- low energy
- injector dump

***ILC Module 1 (DESY “kit”)***

- B

- doublet

- high energy beam dump

- dog-leg test beam-line (TBD)

- HOM couplers

- T

- Y

- F

- T

- B

- C

- O

- B

- O

- S

- O

- B

- T

- O

- O

- Y

- O

- O

- O

- B

- T

- O

- PS

- P

- S

- O

- C

- T

- O

- B

- Y

- O

- B

- B

- O

- B

- O

- T

- B

- T

- B

- O

- B

- T

- O

- B

- O

- B

- B

- B

- test beam-line for advanced beam instrumentation, e.g.
- EOS, Laser-wire,
- OTRI, cavity BPM’s,...

- B

- B

- doublet

- doublet

- correctors

- correctors

- dipole

- O

- B

- T

- doublet

- quad

- dipole

- doublet

- correctors

- ~ 19 meters

- ~ 22 meters

**Layout (preliminary draft) of the ILC Test Accelerator (ILCTA) at the “New Muon Lab” (NML) building – not to scale**

- Basic beam instrumentation:

- Beam current / bunch charge monitor
- (T: toroid)

- Beam position monitor
- (B: button, PS: perpendicular stripline, C: cavity)

- Screen monitor (some multifunctional)
- (Y: YaG, O: OTR, C: CTR, S: slit, F: Faraday-cup)

- Time-of-flight or beam phase monitor

- Synchrotron light bunch length monitor
- (P: pyro detector)

- TDB: beam loss monitors (BLM)

***ILC Module 2 (Made in USA)***

- HOM couplers

- C

- Button-style BPM pickup

- Bunch arrival / beam phase pickup

- Screen monitors(OTR, slits, YaG)

*Faraday*-cup monitor

**“****Cold” L-Band Cavity BPM Development**

**RF Interlock System:**
**Protection of Klystron, ****Input-Coupler and Cavity**

- Developed for use in CC1, CC2, HTS, CTS & NML
- RF interlock system design:
- hardware-based,
-  processor independent,
-  VME64X implemented.
- Several RF interlock systems are now successfully installed, commissioned and operated at CTS, CC1, CC2 and HTS. A revised version will serve as central RF interlock system for up to 3 cryo-modules at NML.
- The primary purpose of the RF interlock system is to protect klystron, cavity and coupler by controlling the presence of RF. The system removes the LLRF permit within 0.2-0.8 μs of fault detection.
- Normal operation: Enable permit to LLRF and modulator using analog hardware and digitize signals for remote monitoring.
- Klystron (FWD & RFL power, window arcs [PMT}, RF leak detection WG pressure).
-  Coupler (PMT, photodiode based arc detection and FEP measurement, ceramic window temperature).
-  Cavity (PMT ard detection, vacuum control FEP HOM couplers).

**OTR Interferometer Development ****at the A0-Photoinjector**

**courtesy *****G. Kazakevich***

- OTRI setup at the A0-Photoinjector

**OTR Interferometer:**
**A beam passing two thin foils, allows the measurement of additional beam parameters (energy, energy spread, divergence), derived from the OTR interference pattern.**

## ILC Instrumentation R&D at Fermilab:

**ILC Instrumentation R&D at Fermilab:**
**Collaboration Activities & Other Efforts**Manfred Wendt*Fermi National Accelerator Laboratory, Batavia, IL 60510, U.S.A.*

**Advanced Beam Instrumentation in the Optical Domain**

**KEK/SLAC/FNAL ATF Damping Ring**
**BPM Upgrade Collaboration**

**DESY/SLAC/FNAL HOM Coupler Signal Analysis Collaboration**

- ATF DR BPM upgrade: overall block diagram

- ATF DR button BPM characteristics

- ATF DR tunnel hardware

- ATF DR BPM upgrade: block diagrams of analog and digital signal processing hardware

- ATF DR BPM upgrade: VME hardware

**Wideband Mode: **
- Single BPM data shows trans. and long. tunes.**WB TBT resolution: ****few μm! **

**Narrowband Mode: **
- 128 kturns, 1kHz BWAfter 50 Hz filter and single shot SVD analysis**NB resolution: **
**200-400 nm! **

**courtesy *****DESY***

**HOM as BPM**
**TE****111-6**** narrow band read-out**
**Beam-based calibration data, to orthogonalize the polarization planes of the excited eigenmodes per SVD algorithm. **
**~ 5 μm resolution**
**HOM as phase monitor**
**Comparison of the leaking 1.3 GHz fundamental (TM****010****) to the first monopole HOM (TM****011****) **
**Broadband Scope analysis  **
**<0.1****0**** @ 1.3 GHz resolution**

- TESLA 9-cell SC cavity and HOM coupler

- HOM coupler signals in time- and frequency domain

- Higher order mode passbands below WG cutoff

**Optical diffraction radiation (ODR):**
**Near field effect between EM fields of the beam close to a conducting screen Intensity:**
**DR impact parameter:**
**Non-intercepting beam measurement!**

- weak radiation

- >>

- DR

-  =

- TR

- <<

- if *a*

**courtesy *****A. Lumpkin***

**Near field ODR Monitoring (ANL/FNAL)**

**EOS Bunch Length Measurement (ANL/FNAL/NIU)**
**ZnTe Pockel’s effect**
**Sampling Methods:**
**Scanning delay**
**Spectral decoding**
**Spatial decoding**
**Temporal decoding**
**  **

**courtesy *****F. Loehl***

**Bunch Arrival / Beam Phase Monitor (DESY/FNAL)**

**Martin-Puplett interferometer**
**Needs many beam pulses to resolve the temporal convolution**
**Difficult to calibrate the detectors**

- View from Top

- Transition
- Radiation

- Electron Bunch

- Coherent

- Incoherent

- View from Top again

- Motorized stage

- Polarizing
- Splitter

- Polarizing
- Splitter

- Input
- Polarizer

- Mirrors

- Mirrors

- Pyro Detector 1

- Pyro Detector 2

- Off-axis
- Paraboloidal
- Focusing Mirror

**courtesy            *****R. Thurman-Keup***

**Detector elements**
**Molectron pyro-electric (cheap, calibration)**
**Golay cell (expensive)**