ILC-CR-0004 Main Linac extension: Implementation status Tuesday, November 3, 2015, 11:35 AM, 25 minutes 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley Overview the most recent “official” release of ILC lattice description files (MAD8 Extended Standard Input Format files), corresponding to the TDR, was made at ALCWS-2015 in April and designated “ILC2015a” https://bitbucket.org/whitegr/ilc-lattices goals of present work: implement Change Request #2 (CR02) … single 4.1 m L* for both detectors merge ILC2015a FF design with T. Okugi design … FF length increased by 11.64 m includes Change Request #6 (CR06) … IP BPM fix error in laser wire chicane length in BSYs … maintain identical e- and e+ systems BSY length decreased by 23.87 m photon path length (undulator exit to target) decreased by 12.23 m ~372 m to ~360 m 40 m drift space in e- system (d/s dogleg) to bypass target infrastructure implement Change Request #4 (CR04) … extension of Main Linac tunnels pLET system (pDR → IP) length increased by 2965.609 m (after changes mentioned above) part of length increase in pLTL, part between pBC2 and pML, the rest at the end of pML (before pMPSCOL) includes Change Request #10 (CR10) … BC1 and BC2 part of Main Linac path length difference (e-/e+) set to 10 x CDR FF offset got 28.5453 mm bigger (old: 1.6652 m; new: 1.6938 m) 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley LTL to turnaround match LTL FODO cells DR extraction turnaround BC2 to Main Linac match Return Line Main Linac Main Linac extension IP 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley e+ system changes for CR04 pLTL add 20 “RETURNCELLC” FODO cells after MARKer “M_8_cell_end” did NOT change FODO cell length (still 72.493 m cell length) add 32.939 m to “RTMATCH” beamline just upstream of turnaround rematch return line to turnaround pBC2 add 88.5 m to “BC2_ML_2” beamline (matching between pBC2 and pML) rematch pBC2 to pML pML inserted space for an additional complete 12-string (36 ML unit) cryo unit … details to follow pBSY shorten laserwire chicane from 76.9 m to 42.6 m shorten center drift from 11.5 m to 5.0 m replace eight (8) quadrupoles used to match to FF through polarimeter chicane old: length = 3 m, bore = 80 mm new: length = 2 m, bore = 12 mm rematch BSY to FF through polarimeter 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley LTL turnaround LTL FODO cells 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley LTL turnaround RTMATCH 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley kickers BC2 Main Linac BC2_ML_2 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley Main Linac BSY DUNIT1 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley positron Main Linac extended at downstream end (before MPS collimation) inserted space for an additional complete 12-string (36 ML unit) cryo unit include space for end boxes, service boxes, and warm drifts same quadrupole center-to-center spacing as Main Linac same cryo unit-to-unit spacing as Main Linac replace cryogenic quadrupoles with BDS “Q75L2000” magnets core length = 2 m, bore = 75 mm maintain Main Linac optics (β-functions) no additional cryomodules included (drifts, quads, BPMs, XCORs, and YCORs only) if populated with cryomodules, would provide an additional ~30 GeV of acceleration 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

From “TDR lattice (2015a) review and status” (ALCW-2015) https://agenda.linearcollider.org/event/6557/session/7/contribution/77/material/slides/1.pdf Recreating the TDR CFS geometry subsystems comments EBSY1 / EBSY2 PBSY1 / PBSY2 Redefinition errors discovered during “deck integration”: polarimeter chicanes were copied from *BSY2 to *BSY1 as separate laserwire detection chicanes names of elements (bends and drifts) were not changed names of parameters that defined bend and drift lengths were not changed values of parameters that defined bend and drift lengths were changed in *BSY1 files when *BSY1 file is loaded, LW chicane is 45.1 m long when *BSY2 file is loaded, LW chicane is redefined to be 76.9 m long (ΔL = 31.8 m) TDR CFS coordinates include BSY LW chicanes that are each 31.8 m too long PBDS was 0.95 m shorter than EBDS due to rematching between PBSY and PFFS, so: shorten PMPSCOL by 0.95 m and rematch modify PBSY2 such that EBDS and PBDS are now identical redefine TDR CFS coordinates for TPML2BDS Treaty Point (e+) to be symmetric w.r.t. IP with TPS2EBDS treaty point (e-) 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley MPS collimation FF kickers 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

From “Report of Global Timing Working Group” EDMS number: D00000001097725 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

From T. Okugi’s presentation at POSIPOL2015 ΔS = ±340 mm From T. Okugi’s presentation at POSIPOL2015 https://eventbooking.stfc.ac.uk/uploads/posipol/posipolokugi20150902.pdf 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

From “SB2009 Proposal Document” https://ilc-edmsdirect.desy.de/ilc-edmsdirect/file.jsp?edmsid=D00000000900425 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley Continuing Work MAD8 SURVEY tape-file output precision (10 digit) is too small for total LET (length > 32 km) … need to use sum(Li) for μ-level precision! investigate using MAD-X instead of MAD8 fix path length between kickers and septa in DR (127 μm + 32 μm = 159 μm error) make identical modifications to electron systems DR injection/extraction model space for 12-string (36 ML unit) cryo unit in eML FODO cells in eLTL add path length adjustment chicane in e+ source system Okugi-san’s chicane after booster linac (same location relative to booster linac) assume ±230 mm range (as specified in CR04) … set initially to +230 mm and readjust path lengths don’t move booster linac or include new energy compressor yet (Change Request) verify BSY laserwire chicane offset large enough for laserwire photon detection old (polarimeter) chicane offset was 20 mm … offset now is 8 mm don’t change eBSY fast abort line (requires further study) shift all Treaty Point coordinates to restore IP to origin (0,0,0) earth’s curvature following and vertical dispersion only if time permits release ILC2015b in 2015 (!) 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley Conclusions and Outlook implementation of CR-0004 is about 50% complete need to apply positron system modifications to electron systems need to add positron path length correction chicane need to shift coordinate system / Treaty Points to restore IP at origin (0,0,0) still hoping to finish in 2015! e+/e- path lengths now differ by exactly 10 x CDR (within 1 μm) there are sub-millimeter path length errors in DR Injection/Extraction layout to fix all changes (such as they are) will be available from the Lattice Repository (from the “dev” branch) ILC2015b to be next release 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley

LCWS2015 : Beam Dynamics / M. Woodley End Thanks! 11/3/2015 LCWS2015 : Beam Dynamics / M. Woodley