FLASH. Free-Electron Laser in Hamburg Overview and Status of the Standard Electron Beam Diagnostics at FLASH N. Baboi, DESY for the Diagnostics Team

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 2 FLASH. Free-Electron Laser in Hamburg Contents > Overview of standard beam diagnostics in FLASH1 and FLASH2  General characteristics > Beam monitors  Charge Monitors  Position Monitors  Size Monitors  Loss Monitors  Not all monitor types covered by this talk

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 3 FLASH. Free-Electron Laser in Hamburg Overview of Electron Beam Diagnostics in FLASH FLASH1FLASH2 Charge Toroids125 Dark Current Monitor1 Faraday Cups3 BPMs633 Transverse Size OTR-Screens~30 Scintillating-Screens17 Wire scanners (MDI)10 Wire scanners (Zeuthen)9 Transverse Position Button-BPMs2612 Stripline-BPMs334 Cold Cavity BPMs6 Cavity BPMs17 HOM-based monitors39 Beam Loss BLMs>70~55 Cherenkov Fibers21 Beam Halo Monitors1x4 Ionization Chambers44

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 4 FLASH. Free-Electron Laser in Hamburg General Characteristics > General  Deliver bunch by bunch measurements, with few exceptions > FLASH1  Most designed for TTF2, for charges of 1nC and higher  Electronics: VME-based, ADCs with 1MHz > FLASH2  Most designed for the E-XFEL Make use of synergies given by the similar time line Some have been designed specially for FLASH(2) or have a temporary solution  Generally based on MTCA-technology 9 MTCA crates for diagnostics installed at FLASH2  Designed for lower charge N. Baboi, IBIC’14, THIXB1 J. Feldhaus, D. Nölle, EPAC2004, p. 262

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 5 FLASH. Free-Electron Laser in Hamburg Charge Monitors / Toroids FLASH1 > All signals go to VME and uTCA- system  3GUN and 10DBC2 have new front-end (amplifier & filter, like in FLASH2) FLASH2 > Temporary solution  Low-gain front-end channel  CAT cables (E-XFEL type under tests M. Werner, IBIC’14, WEPF02) Charge Monitors: Toroids W W W W Front-end Adapter RTM RTM SIS8900 AMC SIS8300 AMP-200 ADC peak ADC base VME (Fl1) uTCA (Fl1&2)

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 6 FLASH. Free-Electron Laser in Hamburg ► Charge Monitors: Toroids (2) Resolution of charge monitors along FLASH(1) (~ 0.4 nC) o FLASH-type (VME) o FLASH2-type (MTCA) old amplifier O FLASH2-type with new amplifier ► Dark current monitor

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 7 FLASH. Free-Electron Laser in Hamburg Toroid Protection System (TPS) 5 MeV 150 MeV1250 MeV Bunch Compressors 450 MeV Accelerating Structures RF Stations Lasers RF Gun Soft X-ray Undulators sFLASH FEL Experiments Photon Diagnostics Beam Dump THz FLASH1 FLASH2 TPS 0 TPS 1 TPS 2 A. Hamdi, DIPAC 2007, p. 349 > Temporary solution using 3 TPS modules designed for FLASH (not yet commissioned)

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 8 FLASH. Free-Electron Laser in Hamburg Charge Monitors: Dark Current Monitor Dark current Bunch 7DBC2, 32m

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 9 FLASH. Free-Electron Laser in Hamburg > Designed by INFN > Some camera-PCs have to be reset/restarted from time to time > Recently had to readjust 3 stations in DBC2  Difficult due to missing fine adjustment 2 are adjusted only for a magnification of 1 > Emittance tool Screens at FLASH1 A. Cianchi, EPAC2004, p , 13:42

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 10 FLASH. Free-Electron Laser in Hamburg Screens at FLASH2 BEAM Optics Axis > Scintillator based (LYSO:Ce), spatial suppression of COTR > Optics:  Look under 45 deg  Uses “Scheimpflug´s” principle to extend depth of field > 10 µm resolution required  single bunch, streaked > Demonstrated at FLASH1 200µm thick LYSO Screen (ON-Axis ) 2 half 200µm thick LYSO Screens (OFF-Axis) Dot Grid Target(spot Ø.50mm) C. Wiebers, IBIC2013, WEPF03

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 11 FLASH. Free-Electron Laser in Hamburg Screens at FLASH1 (2) > Fully commissioned FLASH2 FLASH1 1FL2SEED4 1FL2SEED61FL2SEED7 1FL2SEED5

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 12 FLASH. Free-Electron Laser in Hamburg > One horizontal and one vertical fork, each with 3 wires  Used also for cross-calibration of BPMs > Tool for profile scans and emittance Wire Scanners: Zeuthen Type P. Castro, DIPAC 2005, p. 205

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 13 FLASH. Free-Electron Laser in Hamburg > One fork placed at 45deg with horizontal, vertical and diagonal wire  Several WS use one detector  Also possible to read signals from BLMs, with some change in the beam profile  Some have some readout/timing problems, now under work  Jddd panels to be updated Wire Scanners: MDI/CERN Type M. Werner, DIPAC 2001, p. 139

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 14 FLASH. Free-Electron Laser in Hamburg > Button BPMs, stripline BPMs, cold cavity BPMs, button BPMs inside undulators BPMs in FLASH1 ~0.35 nC

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 15 FLASH. Free-Electron Laser in Hamburg BPMs in FLASH2: Cavity BPMs > Cavities  Dipole + reference resonator  3.3 GHz, low Q (about 70)  17 installed between undulators – 10 mm pipe  No individual tuning > Readout (PSI)  MBU (Modular BPM Unit) with 2 RFFE for 2 cavity BPMs  Up to 4 MBUs connected to 1 DAMC2 interface board  Timing: decoding timing protocol via fiber in MBU > Resolution requirement  2  m rms for nC and within ± 0.5 mm (1  m at XFEL, but longer cables at FLASH2) M. Stadler, IBIC’14, WEPD12 B. Keil, IBIC’14, WEPD11

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 16 FLASH. Free-Electron Laser in Hamburg > BPMs in FLASH2  Difference between expected and measured position with Gaussian fit BPMs in FLASH2: Cavity BPMs: Resolution > Test BPMs in FLASH1  0.5  m rms for 0.24 nC bunch charge and 0.5 mm bunch offset Resolution of various FLASH1-BPMs (designed for 1 nC) ~0.35 nC preliminary D. Lipka, IBIC’14, TUPF07

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 17 FLASH. Free-Electron Laser in Hamburg BPMs in FLASH2: Cavity BPMs: Charge > Charge resolution for 100 pC bunch charge < 0.2 pC rms D. Lipka, IBIC’14, TUPF07

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 18 FLASH. Free-Electron Laser in Hamburg BPMs in FLASH2: Button and Stripline BPMs > Low Charge BPMs (LCBPM) electronics  Name chosen in contrast to system designed for FLASH for charges of 1nC and higher  Designed for FLASH2 (and to be installed in all FLASH) Button or Strip-line BPM Delay ~100ns Broadband RF Combiner RF cable 3/8“ Length < 80m Signal of horizontal plane, delay line: ~100ns TYPICAL SIGNALS FROM BUTTON/STRIP-LINE BPM B. Lorbeer, IBIC’14, TUPF08 F. Schmidt-Föhre, IPAC’14, THPME117 S. Vilcins, IBIC’14, TUPF11

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 19 FLASH. Free-Electron Laser in Hamburg BPMs in FLASH2: Button and Stripline BPMs: LCBPM Rear Transition Module (RTM) 180mmx162mm Compatible with the MTCA.4 for physics standard RF Front-End MicroTCA crate X-Channel Y-Channel 100ns Crate used for the tests includes: management carrier hub (MCH) hard disk (HD), processor (CPU) Digitizer SIS8300 timing module x2timer RTM Analog Output Signals G=38dB Att.>60dB Peak Detector 5 BPMs/crate Front Side Back Side

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 20 FLASH. Free-Electron Laser in Hamburg BPMs in FLASH2: Button &Stripline BPMs: Operation RMS at q=36 pC, 200 pulses (incl. beam jitter) Server Panel for Firmware Adjustment BPM Expert Panel Strip-Line BPM Button BPM  y = 22  m  y = 39  m bunch charge0.1-1nC bunch spacing≥222ns maximum macro-pulse repetition rate25Hz beam pipe diameter40.5mm single bunch resolution50μm Averaged RMS resolution over 1000 bunches of identical train10μm Range for max. resolution+/- 3mm Operation range with reasonable signal+/-10 mm Requirements (from XFEL requirements)

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 21 FLASH. Free-Electron Laser in Hamburg HOM-based Position Monitors > Monitor dipole, beam position correlated, signals excited in the accelerating cavities  Amplitude shows the beam alignment in the cavities, which influences the (transverse) beam quality  Available in ACC1 (3 cavities), ACC39 and ACC2-5 Display only signal envelope

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 22 FLASH. Free-Electron Laser in Hamburg Beam Loss Monitors in FLASH1 Cannot distinguish between losses from FLASH1 and FLASH2 pulses

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 23 FLASH. Free-Electron Laser in Hamburg Beam Loss Monitors in FLASH2 > Detector  Scintillator or fused silica (rod or fiber)  PMT: HV voltage (~500 V) generated by Cockcroft-Walton multiplier on board mounted at PMT  Scintillators and mechanics built by IHEP, Protvino (60 for FLASH2) > Electronics MTCA-based with low latency interface with MPS > Alarms algorithms  Single bunch  Multi-bunch  Integration  OR of comparator and FPGA alarms Readout Electronics Power control PMT & HV Scintillator Beam Loss Monitor e, γ,n 0 Alarm (to MPS) A. Kaukher, BIW 2012, p. 35

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 24 FLASH. Free-Electron Laser in Hamburg Beam Loss Monitors in FLASH2: Status > Calibrated single and multi-bunch alarm > Integration alarms to be calibrated

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 25 FLASH. Free-Electron Laser in Hamburg Dump Loss Monitors in FLASH1 & FLASH2: BLMs and Ionization Chambers > BLMs based on quarz-fiber + Ionization Chambers (air filled cables) along last 2m of beam line > VME/uTCA electronics beam FLASH1 N. Baboi, BIW 2010, p. 420

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 26 FLASH. Free-Electron Laser in Hamburg Dump Loss Monitors: Beam Halo Monitors (FLASH1 & FLASH2) > Installed behind dump vacuum window  8 sensors: 4 Diamond + 4 Sapphire > VME-based in FLASH1 > uTCA-based in FLASH2  Basically same electronics and firmware as FLASH2 BLMs  Under commissioning FLASH1 A. Ignatenko, IPAC 2012, p. 816

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 27 FLASH. Free-Electron Laser in Hamburg Acknowledgement > Many people contributed to the work and this talk  R. Neumann, D. Lipka, N. Wentowski, Z. Pisarov, M. Werner, J. Lund-Nielsen, B. Lorbeer, A. Kaukher, T. Wamsat, A. Ignatenko, F. Schmidt-Föhre, K. Honkavaara, H. Tiessen, B. Michalek, R. Zahn, B. Keil, D. Nölle, O. Hensler, G. Marinkovic, K. Knaack, J. Schwarz, J. Liebing, H. Sokolinski, G. Kube, C. Wiebers, M. Felber, R. Zahn, S. Vilcins, J. Kruse, D. Renner, M. Felber, S. Schreiber, M. Holz, M. Pelzer, A. Ziegler, M. Hoeptner, H. Sokolinski, M. Stadler, M. Wendt, I. Krouptchenkov and many others Thank you !

Nicoleta Baboi | Electron Beam Diagnostics at FLASH | FLASH Seminar | DESY, Hamburg | Nov. 11, 2014 | Slide 28 FLASH. Free-Electron Laser in Hamburg Other Electron Beam Monitors in FLASH2 > Loss monitors  Cherenkov fibers along undulators (not for XFEL) > Beam Compression Monitors > Beam Arrival Monitors > Coherent Transition Radiation monitors C. Behrens, IPAC’10, p.912 A. Angelowski, IBIC’14, MOPD25 S. Wesch, BIW 2012, THAP01