15Hz Muon Beam

1. 15Hz Muon Beam Beam to MuCool Test Area for Cooling Experiments Part 2 (comments) M. Popovic March-15-07

2. Introduction • The Linac can accelerate much more beam than the Booster can. • Existing Linac beam-splitting capabilities can be used to share each 15-Hz Linac beam pulse between the Booster and the MTA. • Using existing enclosures, new beam line can parasitically deliver at least 50 ms of spill containing up to 1.4 x 1013 protons to the production target at a 15 Hz rate • This is 0.75 ms of spill and 2.1 x 1014 protons per second

3. Questions Can we pulse extraction of Carol’s Line

4. Questions Can we pulse extraction of Carol’s Line To replace the first fast magnet (the 10 inch long magnet) in Carol’s design, the needed kick is ~50 mradians. Electrostatic deflection, 10-20 nsec: The present Chopper is a 60 kV system. It has a plate length of 1.5 meters and a gap of 2.5cm. This system produces a 5 mradian kick. Booster Extraction Kicker, 20-40 nsec: The kick is 5.3 microradians/kV of PFN voltage at 8 GeV. Booster PFNs run at 65kV. Each kicker is one meter long. At 400 MeV this kicker can produce 3.2 mradians kick per meter.

5. Questions Can we pulse extraction of Carol’s Line Fast pulse magnet, 1-2usec: A system with a rise time of 1.5 microsec will need a power supply that can deliver 20 kV, 3 kA to a four-turn magnet; the pulse has to be on for 50 microsec. This cannot be a half-wave power supply, so it will not be a simple and cheap power supply.

6. Questions-Conclusion 1 Can we pulse extraction of Carol’s Line • It looks to me that fast (rise time in tens of nanoseconds) system based on new chopper and/or kicker will be very hard to make. • For the system with microsec rise time we will need new pulse magnet, new (demanding) power supply, new Lambertson (as replacement of second pulse magnet in Carol’s design) and power supply for Lambertson. Then we will need beam notching system to make hole in linac beam for 1.5microsec.

7. Questions • Cost and duration of civil construction? • I talked with Russ Alber about cost and duration of the civil work. • Option with no target in the wall: • Based on some work done for MiniBoone, making a 36-inch hole in the wall will cost about $10K to $15K, and it will take not more than five days of tunnel work. • b. Option with target and solenoid in the wall: • Based on excavation work done for Booster kicker feeder, excavation from the top of the berm and making transfer hall between two enclosures will take five weeks and will cost not more than $100k.

8. Conclusion -2 One more time, I think that the hole in the wall, two new bending magnets (spectrometer type) and the whole line connecting Diagnostic Line and Carol’s line will not cost more than $200k. If there is interest to do it on the cheap, we can use Cooling Ring Dipoles and pulse magnets that are made for Carol’s line and save on the cost of building two new spectrometer type dipoles.

9. References A Simple Beam Line for the MuCool Test Area http://www-mucool.fnal.gov/mcnotes/public/pdf/muc0287/muc0287.pdf Upgrading the Linac 400 MeV Switchyard http://www-mucool.fnal.gov/mcnotes/public/pdf/muc0294/muc0294.pdf Stay tuned for write up about this work

10. Linac Diagnostic Area

11. Transfer Hall to MTA

12. Linac, MuCool, Booster

13. Linac, MuCool, Booster