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  1. Intro
  2. Hazard Summary
    • Pretty big table on page 5. Worth a glance
      • Lists general types of hazards, what they could do, how we're controlling for them, how likely they are to happen, and severity/risk 
    • Definition of Risk on page 9
      • Risk is a function of probability and severity (high severity + low  probability = low risk, high + high = high, low + low = low)
  3. LAF Description
    1. LAF Subsystems
      • Copper linac through the FEE, FACET-II facility, ESA, LCLS II RGD
      • Copper
        • 2856 MHz, room temp, klystrons, SLED cavities
        • 25 feet under gallery
          • Gallery has klystrons, SLED cavities/modulators, power supplies, cooling water systems
        • 31 sectors (0 in the west, 30 in the east)
          • Each sector ~100 m long
        • Linac West (S0 - 9)
          • decommissioned and removed for superconducting LCLS-II (currently under construction)
        • Linac Middle (S10 - 19) and Linac East (S20 - 30) separated by concrete shielding wall and personnel passageway maze
          • Can be operated independently 
          • But share control and water cooling systems
        • People can't be in Linac East if Linac Middle is running
          • prompt radiation risk exposure 
        • Max pulse rate is 120 Hz
          • 30 Hz if 120 isn't needed or to reduce power consumption
          • Linac East and Middle can be operated at different rates
            • Usually 30 Hz for FACET-II (the usually is suspicious here considering we haven't run it yet)
            • Usually 120 Hz for LCLS
        • Linac Middle
          • Max energy of ~16 GeV to FACET-II
          • Positron beam coming in the future when they build a damping ring
          • Not designed to go above 30 Hz 
        • Linac East
          • Max energy of ~18 GeV to Undulator Complex (has two undulator systems)
            • Generate coherent x-ray beams that can be sent to the NEH and FEH
          • Has previously sent beam to ESA, but that's currently decommissioned 
            • Could be brought back if needed
      1. LCLS-II Injector
        • Normal conducting laser-driven photocathode gun (186 MHz) followed by a buncher cavity
        • Currently set up to deliver electrons to a Faraday cup for commissioning without additional accelerationThere's currently a concrete shielding wall immediately downstream of the Faraday cup
          • Will be removed before the injector is connected to the superconducting linac
          It's currently a Radiation Generating Device (not an accelerator)
          • Will be reclassified when it's connected to the linac
      2. Linac West
        • LCLS-II injector through Sector 9
        • Currently under construction
      3. FACET-II Injector
        • At Sector 10
        • Produces electrons for acceleration in Linac Middle & delivery to the FACET-II experimental area in S20
        • Normal conducting S-band laser-driven photocathode gun
      4. Linac Middle
        • Middle third of the linac, sectors 10 though 20
        • Designed to accelerate, compress, & focus electron or positron beams to the FACET-II experimental area in S20
        • Magnetic chicane bunch compressors in sectors 10 and 14 shorten the electron beams longitudinally (increasing intensity)
        • Currently unable to produce positron beam
      5. Positron Source
        • Can produce positrons by slamming electrons into a target near S19
          • The target is a plate of high-density, water-cooled tungsten-rhenium
          • It's slowly rotated so that the heat from the beam is dissipated over a higher area
        • Target is followed by RF capture and acceleration sections that make a 200 MeV positron beam
        • You can park all or some portion of the e- beam on (in?) the transport line from S19 to the target
        • We currently can't transport, damp, or reinject positrons in to the linac (all that stuff was decommissioned)
      6. FACET-II Experimental Area
        • In S20
        • Beam transport and focusing system, followed by an area to mount experimental setups, followed by a beam dump
          • The transport and focusing system has diagnostic devices and magnets 
            • Focuses the beam to a small spot size at the experimental setup
            • Compresses the bunches longitudinally for "very" high peak current
      7. LCLS Injector
        • S20
        • Produces electrons for acceleration in Linac East
          • Which drive the LCLS FELs in the Beam Transport Hall 
        • Normal-conducting, laser-drive photocathode S-band gun 
      8. Linac East
        • LCLS uses last kilometer of linac (S21 through 30)
        • Produces ~2 to 17 GeV
          • Dependent on number and configuration of klystrons 
        • Beam lines and shielding could safely transport and dissipate 25 GeV e- beam
        • Magnetic chicane e- bunch compressors in S21 & 24 shorten the e- bunches longitudinally
          • The chicanes divide Linac East into five LCLS areas:
            • Linac-1 (L-1)
            • Bunch Compressor-1 (BC-1)
            • Linac-2 (L-2)
            • Bunch Compressor-2 (BC-2)
            • Linac-3 (L-3)
      9. Beam Switchyard
        • BSY
        • Provides switching, energy definition, collimation, and transport functions for LCLS and ESA beams
        • Can send compressed e- bunches to either transport line to the BTH on a pulse-by-pulse basis
        • Has beam dumps that can stop and safely dissipate e- beam
      10. A-Line to End Station A (ESA) and Beam Dump East (BDE) 
        • ESA is a facility for fixed target experiments 
  4. Hazard Analysis
  5. ASE
  6. QA
  7. Post Ops
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