Status of MERLIN and Recent Developments Haroon Rafique

Status of MERLIN and Recent Developments Haroon Rafique On behalf of the MERLIN group: R. B. Appleby, R. Barlow, S. C. Tygier In Collaboration with CERN: R. Bruce, A. Santamaría, S. Redaelli, J. F. Wagner

Contents MERLIN LHC Collimation using MERLIN HEL process CC Failure process What next? 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 2

MERLIN

MERLIN C++ Accelerator Physics Library (N. Walker @ DESY, storage ring functionality added by A. Wolksi) User writes their own simulation containing: – – Beam -> Bunch Accelerator Model (MAD. tfs table) Tracker (different integrators available) Physics Processes (user defined / pre existing) Modular – easier to use Extensible – if you have the physics, adding a process is trivial 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 4

Merge • Consolidation of processes: – Collimation (scattering, binning, etc) – Hollow Electron Lens (HEL) – Crab Cavity Failure • • • Clean up Optimisation Test suite Cmake Git history 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 5

Former Developers Thanks to all: • James Molson • Maurizio Serluca • Adina Toader • Adriana Bungau • Andy Wolski • Others …? • Dirk Krücker • Nick Walker 30. 15 [Manchester] [Liverpool] [DESY] Haroon Rafique Hi. Lumi 15 WP 5 Workshop 6

COLLIMATION USING MERLIN

Typical User Code Aperture. Configuration Collimator. Database Lattice. Function. Table MADInterface Beam. Data Accelerator. Model. Constructor Accelerator. Model Proton. Bunch Collimate. Proton. Process 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop Particle. Tracker 8

Apertures 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 9

HL LHC Optics 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 10

Integrator MERLIN includes 3 standard integrator sets: 1. TRANSPORT 2. SYMPLECTIC 3. THIN_LENS my. Particle. Tracker->Set. Integrator. Set (new Particle. Tracking: : SYMPLECTIC: : Std. ISet()); my. Particle. Tracker->Set. Integrator. Set (new Particle. Tracking: : TRANSPORT: : Std. ISet()); Legend: Class User object Function Variable 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 11

TRANPSORT vs SYMPLECTIC 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 12

Synchrotron Motion 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 13

Collimation Process Collimate. Particle. Process Material Collimator Collimate. Proton. Process pp. Diffractive. Scattering. Model Cross. Sections pp. Elastic. Scatter Path. Length() Configure() Energy. Loss() Straggle() Scattering. Process Scatter() Particle. Scatter() Dustbin Death. Report() 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 14

Scattering Processes Six. Track+K 2 – like & MERLIN scattering for: § Rutherford § Elastic pn § Elastic p. N § SD § Inelastic 30. 15 Six. Track & ST + Ad. Ionisation § ST Rutherford § ST Elastic pn § ST Elastic p. N § ST SD § Inelastic ST + Ad. SD ST + Ad. Elastic § ST Rutherford § ST Elastic pn § ST Elastic p. N § SD § ST SD § Inelastic Merlin § Rutherford § Elastic pn § Elastic p. N § SD § Inelastic Haroon Rafique Hi. Lumi 15 WP 5 Workshop 15

Scattering 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 16

HOLLOW ELECTRON LENS PROCESS HR & Joschka Wagner @ CERN

Poincaré Sections • HEL @ s = 10037 m (40 m downstream of IP 4) in LHC lattice (RB 46) • 104 – 105 turns in the LHC – Nominal v 6. 503, HL v 1. 2 • Output particle data @HEL position every turn • Plot xx’ phase space to see effect 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 18

Six. Track vs MERLIN: DC Identical Six. Track bunch Six. Track MERLIN 4σx ≈ 1. 17 mm 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 19 Parameter Value LHC lattice Nominal HEL hardware Tevatron Mode DC I [A] 1. 2 Ee [Ke. V] 5 L [m] 2 Rmin [σx] 4 Rmax [σx] 6. 8 Distn Six. Track 1 -10 σx

Six. Track vs MERLIN: DC Different initial bunch for clarity Six. Track (using Six. Track bunch) MERLIN (using MERLIN bunch) 4σx ≈ 1. 17 mm 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 20 Parameter Value LHC lattice Nominal HEL hardware Tevatron Mode DC I [A] 1. 2 Ee [Ke. V] 5 L [m] 2 Rmin [σx] 4 Rmax [σx] 6. 8 Distn Six. Track (Left) MERLIN (Right) 1 -10 σx

Nominal vs HL LHC: DC Identical MERLIN bunch MERLIN nominal 30. 15 MERLIN HL Haroon Rafique Hi. Lumi 15 WP 5 Workshop 21 Parameter Value LHC lattice Nominal (left) HL (right) HEL hardware LHC Mode DC I [A] 5 Ee [Ke. V] 10 L [m] 3 Rmin [σx] 4 Rmax [σx] 8 Distn MERLIN 1 -10 σx

HL LHC: AC vs Diffusive Identical MERLIN bunch AC 30. 15 Diffusive Haroon Rafique Hi. Lumi 15 WP 5 Workshop 22 Parameter Value LHC lattice HL HEL hardware LHC Mode AC (left) Diffusive (right) I [A] 5 Ee [Ke. V] 10 L [m] 3 Rmin [σx] 4 Rmax [σx] 8 Distn MERLIN 1 -10 σx

Cleaning: nominal vs HL LHC Nominal LHC 30. 15 High Luminosity LHC Haroon Rafique Hi. Lumi 15 WP 5 Workshop 23

CRAB CAVITY FAILURE PROCESS HR & Andrea Santamaria Garcia @ CERN

Simple Kick Model Andrea Santamaría García 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 25

Thin CC Kick Vertical crabbing @ IP 1 (ATLAS) 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 26

Closed Bump Bunch at TCP after a full ‘CC’ turn ‘Pre tracked’ IP 1 -> First ATLAS CC Y [m] ‘Tracked + CCF Process’ First ATLAS CC -> 1 turn ‘Post tracked’ First ATLAS CC -> IP 1 Holds for many turns ct [m] 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 27

4 CC 90° Phase Failure A. Santamaría (Wednesday) MERLIN (Thursday) 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 28

FUTURE

Documentation • Sourceforge (not up to date) • Git. Hub (in near future) • Current git repository is private • HR merlin site: https: //sites. google. com/site/haroonrafiquemerli n/ • HR HEL site: https: //sites. google. com/site/hollowelens/home • HR thesis – early 2016 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 30

Future Work Run side-by-side with Six. Track for HL LHC (J. Wagner @CERN) Use of CC failure model (A. Santamaría @ CERN) HEL integration study (A. Rossi @ CERN)? Support of MERLIN use @ CERN (A. Valloni + many more) CC failure + HEL + Loss Maps? S. Tygier – HL squeeze loss study Always welcome new users / new applications H. Rafique Ph. D Thesis (Early 2016) All of the above + MERLIN manual 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 31

Future HEL Work 1. MERLIN vs Six. Track for identical bunches, various operation modes (Poincare Sections) 2. Investigation of optimal AC mode parameters in HL v 1. 2 3. Investigation of optimal HEL position in HL v 1. 2 4. Cleaning enhancement with more realistic TCP setting (use 6. 2 sigma now, possibly 6 or 5. 7 sigma in future) for all modes 5. Cleaning enhancement with scattering (for all modes) - currently use TCP as a black absorber 6. Cleaning enhancement with a full collimation scheme (for all modes) 7. Cleaning enhancement for all above with a more realistic bunch (for all modes) 8. Crab Cavity failure model 9. Loss map with CC failure 10. Loss map with HEL and CC failure (with HEL halo depletion post, pre, and both post & pre CC failure) 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 32

Acknowledgements J. Molson & M. Serluca R. Bruce & S. Redaelli A. Santamaría D. Mirarchi & J. Wagner A. Valloni – MERLIN development – Collimation – CC failure – HEL – Sanity check Questions? 30. 15 Haroon Rafique Hi. Lumi 15 WP 5 Workshop 33