100th ATF2 weekly meeting

International phone/webex meeting

Beam orbit tilt monitor studies at ATF2, Daisuke Okamoto (Tohoku university) , Tomoyuki Sanuki (University of Tokyo)

We are developing a rectangular cavity to measure the tilt. The signals are monopole modes in vertical and horizontal modes at 2.856 and 3.927 GHz, respectively, which are excited by tilts of beam.

The resonances were measured with S11 reflection signals which go to zero at the resonances. The loaded Q are designed to be 2700 and 3700 by the S21 transmission amplitude for decayed out until the next bunch.

Sensitivities will be limited by thermal noise, which is P = kT delta_f, where delta_f=3MHz. The P is estimated to be 1.24 x 10^-14 W. Nominal beam has the charge of 1.6nC and sigma_z=8mm . The sensitivities are expected to be 80nrad and 300nrad in vertical and horizontal directions, respectively.

Q : How much improvements is expected from ones by the IPBPM ?

Q : Where is it located?

A : at IP

Q : Does the sensitivity depend on the beam size ?

A : no dependence

Q : Does it depend on beam position ?

ATF2 flight simulator update, Glen White (SLAC)

Q : model includes DR, BT and LINAC ?

Q to M.Pivi - SAD ?

A : SAD and AML interface will be tested in next week at KEK.

Q : SAD interface can be used for optics fitting ?

A : It is one of goal.

Q : there are differences such as stray fields in various optics programs.

A : To resolve the difference is a job of parser, which should be translated from the AML baselines.

Q :( interface to SAD ) How does SAD work in FS?

A : It depends on the developer.

Q : What is the present status of Shintake monitor ?

The group is now busy for the hardware preparation. So, the software preparation would be the next. It takes half year to prepare the interface to the ATF control system . First, we use a laserwire mode, then go to the 2 degree and 8 degree for um sizes.

Q : How to change V and H modes and how long does it take ?

A : It takes a few minutes.