Linac4 BCC 14/10/2010 Linac4 Measurement and Dump Lines BCC on the Linac4 Transfer Line Status

Linac4 BCC 14/10/2010B. Mikulec, T. Hermanns2 Reminder LT.BHZ20 LTB.BHZ40 Linac4 Transfer Line Dump Line LBE Line LBS Line LBE Line LBS Line

Linac4 BCC 14/10/2010 Linac4 Dump/Measurement Line Linac4 dump line will be extensively used during Linac4 commissioning. Regular (although reduced) use during subsequent normal beam delivery to the downstream machines. Main usage of the line:  For Linac4 standalone operation  Dump the beam during optimization of various Linac4 parameters  Dump the beam during Linac4 MDs  For transverse emittance measurements: Requires different settings for both quadrupoles in the line (to obtain the value in both planes), steering and sequential operation for 3 screen/camera systems During Linac4 commissioning, operation with reduced pulse length and/or beam current is envisaged. The dump will not be used for beam interlock purposes. B. Mikulec, T. Hermanns3

Linac4 BCC 14/10/2010 Status of Linac4 Dump Line B. Mikulec, T. Hermanns4 Present Status:  The layout of the line has been fixed. To be on the safe side, another steerer magnet should be added between the first screen and the transformer.  First drawings are available.  Equipment specifications have been provided; EDMS document on beam dump specifications has been released. Still to be done before installation:  Final design of magnets, BI equipment.  Final drawings of equipment, supports and layout.  Modified dump design including Fluka simulations. Evaluate dose levels at equipment positions close to dump and where required.  Application programming at FE and higher layer levels.

Linac4 BCC 14/10/2010 LBE Line The LBE line will be extensively used during Linac4 transfer line commissioning. After this period, the line will only occasionally be used for transverse emittance growth control of Linac4 (Linac3?) Main usage of the line:  For Linac4 transfer line commissioning  For special MDs  For Linac4 transverse emittance measurements: Requires different settings for both quadrupoles in the line (to obtain values in both planes), steering and sequential operation for 3 screen/camera systems  Linac3 transverse emittance measurements: no changes planned During Linac4 transfer line commissioning, operation with reduced pulse length is envisaged. Interleaved pulse trains of a few pulses (~10) with the full pulse length. The dump will not be used for beam interlock purposes. B. Mikulec, T. Hermanns5

Linac4 BCC 14/10/2010 Status of the LBE Line Present Status:  The layout of the line has been fixed. It will be compatible with ion operation.  Laser scanning of the line done to prepare an integration drawing.  Equipment specifications have been provided; EDMS document on beam dump specifications has been released. Still to be done before installation:  Final screen and camera design (same as for Linac4 dump line), equipment and support drawings and layout.  Add water-cooling to quadrupoles, exchange power converters  Move steerer dipole.  Dump design.  Beam pipes. B. Mikulec, T. Hermanns6

Linac4 BCC 14/10/2010 LBS Line The LBS line will be extensively used during Linac4 transfer line commissioning. After this period, the line will only occasionally be used to check energy and energy spread of Linac4 (and Linac3). Main usage of the line:  For final Linac4 commissioning once transfer lines are available  For commissioning of energy painting  For special MDs  For energy and energy spread measurements (Linac4 and Linac3): Select beam slice with slit and correlate particle energy with position on SEM grid after spectrometer (same principle as presently, but new equipment) Operation with reduced pulse length is planned. Interleaved pulse trains of a few pulses (~10) with the full pulse length. B. Mikulec, T. Hermanns7

Linac4 BCC 14/10/2010 Status of the LBS Line Present status:  A layout of the line has been proposed, compatible with ion operation. It will be adapted in case slit dimensions and equipment positions (dump!) would change.  Equipment specifications have been partially provided (depend on final layout); EDMS document on beam dump specifications has been released, slit specifications are under approval.  Laser scanning of the line done to prepare an integration drawing. Still to be done before installation:  Propose slit and dump designs, check compatibility with RP restrictions.  Finalize SEM grid and spectrometer magnet specifications.  Integration drawings needed in addition to layout drawings.  Prepare software application.  Solve problem of lifting existing/ new equipment over BI line.  An alternative method for the energy measurement is under study (next L4/PSB commiss. WG meeting). B. Mikulec, T. Hermanns8

Linac4 BCC 14/10/2010 Summary Design : available for the Linac4 dump line and the LBE line. The proposed design of the LBS line might need some tweaks depending on the dump position and the slit position/design. Specifications : have been provided for the three dumps, the slit, quadrupoles and the emittance measurement screens. SEM grid and spectrometer magnet specifications need finalisation once all equipment positions in the LBS line will be fixed. Outstanding issues : Linac4 and LBE dump designs and Fluka simulations, spectrometer magnet design,... The lifting equipment for the LBS line needs to be upgraded (already in 2012?). Drawing requests : have been announced. Software applications : the preparation time for application programming should not be underestimated (+ action on the two choppers). B. Mikulec, T. Hermanns9

Linac4 BCC 14/10/2010 Backup Slides B. Mikulec, T. Hermanns10

Linac4 BCC 14/10/ L4 Energy Measurement - Plan B Interactions of H - ions with rest gas strip electrons Deflection of stripped electrons into analysis line Slow down/stop electrons with electric field Measure electrons passing the electrical potential in Faraday cup as a function of retarding voltage Remaining p, H 0, H -  Beam dump  Install corrector magnet to re-use remaining H - beam Interactions with Rest Gas  Stripping of Electrons E variable field GND -HV Faraday Cup H-H- p, H 0,H - e-e-

Linac4 BCC 14/10/ L4 Energy Measurement - Plan B Kinetic energy of electrons and H - are correlated  Same velocity of both particle types  H - ions: ~160 MeV  Electrons: ~87 keV Retarding voltage is ~equal to kinetic energy  Some signal loss due to electron absorption at high voltages plates Faraday cup signal  Systematic scanning of electron signal over suitable voltage range  Energy of electrons: O(1keV) Measurement principle already established at BNL Linac  200 MeV H - beam, 30 mA beam current

Linac4 BCC 14/10/ L4 Energy Measurement - Plan B Simulation parameters  Gaussian beams with non-interacting 100,000 particles Variables: energy (mean and spread), voltage and scanning step width Differentiation of measured signal  Energy (mean and spread) Meeting for detailed discussions soon to be organized