nsls-ii injector status

1 BROOKHAVEN SCIENCE ASSOCIATES

NSLS-II Injector Status

T. ShaftanInjection System Group Leader

NSLS-II Accelerator Systems Advisory CommitteeOctober 16-17, 2010


Outline

• Injector design requirements• Injector procurements• Linac• Booster • Storage Ring injection straight section• Pulsed magnet laboratory (PML) • Transport lines• Summary


Injector Requirements• NSLS-II requires a reliable injector capable of filling and maintaining storage ring current.

Top-off mode of injection is required

Repetition rate of 1 Hz (2 Hz) sufficient with multibunch injection: initial fill 00.5 A in 3 min

Storage Ring Parameters Value

Energy, GeV 3Circulating current, A 0.5Circumference, m 792Revolution period, s 2.6RF frequency, MHz 500Circulating charge, C 1.3Total number of RF-buckets 1320Number of filled buckets 13204/51080Charge per bunch, nC 1.25Beam lifetime, hours 3Top-up cycle time, min 1Beam current change between top-ups, % 0.55%Charge variation between top-up cycles, nC 7.3


NSLS-II accelerator milestones• Storage ring schedule contain two

milestones:

• Goals for start-up operations: • Two RF cavities• 21 m of damping wigglers• Low current 50 mA• Emittance 1 nm rad • Stable orbit• Top-off

• Mature facility performance:• Complete RF system• Full current 500 mA

tT0

Ib

tT0

Ib

Bunch patterns

80%/20%

Bunch trains

tT0

Ib

Camshaft

tT0

IbUniform

+


NSLS-II injector

200-MeV linac15 nC/160-300 ns, 0.5% e.s., 50 µmrad

3-GeV booster, C=158m20 mA, 1 Hz, 40 nmrad

LB TL

B-SR TLInjection straight

4


Ongoing injector procurements • Linac

• Four proposals received• Contract awarded to Research Instrument (RI, Germany)

• Booster• Three proposals received• Contract awarded to Budker Institute of nuclear physics (BINP, Russia) • RF transmitter contract has been awarded recently

• Transport line magnets• 7 types in two contracts• Proposals are being evaluated

• Injection straight pulsed magnets• Preparation of specification and SOW is in progress• 4 kickers and 1 septum magnets with PS, vacuum chambers, supports• Considering both in- and out-of-vacuum septa solutions for the proposal


200 MeV linac

• Linac contract has been awarded in April 2010 to Research Instruments (Germany)

• PDR took place in July 2010• FDR is scheduled for October 19• Beam dynamics analysis is nearing completion• Decision has been made to use Solid-State

modulators• Accelerating sections and solenoid magnets are

being manufactured• Linac Front-End will be delivered in April 2011 for

performance verification; diagnostics station is in procurement phaseLinac Front-End

90-keV gun 1st acc. structure 4th acc. structuretriplet

bunchers

solenoids

J. Rose


Linac Beam Dynamics• Linac beam dynamics efforts in parallel

with Vendor• Corroborate vendor results• Supplement vendor work• Obtain tolerances for the components

• Installation of a short drift in the linac front end for installation of a chopper as a future upgrade.

• Chopper will be used to:• Cut the head and tail of bunch train to

provide sharp edges• Deflect certain bunches into an aperture to

shave some of the charge to produce a more uniform charge/bunch in the train.

Phase Space prior to Final Buncher withChopper included

RMS beam sizes along the linac

R. Fliller, G. Wang


Booster• 200 3000 MeV• 36 nm rad, 0.1% energy spread at 3

GeV• 4-fold combined-function FODO

lattice with dispersion suppressors• 32 BD magnets• 28 BF magnets• 24 quads• 16 discrete sextupoles• 40 correctors• 36 BPMs

• 4 straight sections:• RF• Injection

– 1 septum, 4 kickers• Extraction

– 4 bumpers, 1 kicker, 1 pulsed septum, 1 DC septum

• Diagnostics section


Booster• Booster Contract has been awarded to BINP in

May 2010• PDR held in the week of October 11

• BINP team is on site• Detailed lattice design is completed• Major components are designed• Long-lead procurements are on the way: steel,

copper, PS parts, ceramic chambers• Contract on RF transmitter is awarded• Booster FDR will take place at end of January

2011• First articles will be produced by May 2011

• BD, BF magnets• Girder• Kicker• Corrector, sextupole PS

• Installation labor estimate and installation sequence are available

Booster PDR document

dipole

quad

Corrector PS

Cable routing


Beam stacking• 15 nC/160 ns from linac is a challenging

requirement• Looking into ways of reducing this

requirement• One way to reduce charge from linac in

half is beam stacking• Linac generates two 7.5 nC bunch trains

separated by 100 ms. First is stored in the booster until the second train is added.

• Intensive simulations were carried out to ensure high injection efficiency

• It is determined that more than 90% of two beams will be captured for subsequent acceleration to 3 GeV

• Kicker requirements (15 mrad in 300 ns with raise/fall time of 100 ns) are quite challenging

• Submitted to PR ST AB

R. Fliller


Injection Straight section

• Injection straight section design is ongoing• Two options considered: in- and out-of-vacuum septa• Preliminary design of magnets, vacuum system is completed• Preliminary impedance analysis is completed• Injection Straight section review took place in Sept 2010

• Reviewers from ALS, Diamond, SLS, SLAC, APS, NSLS-II, SPRING-8• Review report is coming in October

• Procurement documents for 4 kickers and septum magnet are being prepared; potential bidders are identified

• DC septum is a copy of the booster extraction septum and will be delivered by BINP

• Contract award for Injection straight section pulsed magnets is February 2011• Testing of the 1st article and final magnets at Pulsed Magnet lab

septum kicker

DC septum

vac. pump,absorber

M. Ferreira et al.


DC/Slow ramping bump at injection straight

• To improve the fast bump stability and reproducibility, three DC/slow ramping correctors are used as a local bump to lower the fast bump kick strength. • The max. bump amplitude at the septum

knife is 5mm to maintain the stored beam lifetime and to keep the injected beam away from the septum knife. • The DC/slow bumper strength is 2.5mrad. • The fast bumper strength reduces by a factor

of 1/3. The corresponding error tolerance is 1.5 times bigger.

*DCfs1: DC bump + fast bump (different fast bump amplitude) DCfs2: DC bump + fast bump (equal fast bump amplitude)

DC/slow bump

fast bump

G. Wang, F. Willeke


Transport Line Status• Transport Line Optics Designed

• Magnet Vendor proposals are being evaluated

• LtB Vacuum chamber design is underway

• Some diagnostics are in house, other procurements are underway

• Stands and support structures are being designed for LtB, similar stands will be used for BtS.

• Supplemental shielding is being designed, locations are understood for LtB.

• Current focus is on the LtB since that will be the first installed.

• Assembly area designated in Mechanical Equipment Room of Injector Service Building.

Linac to Booster Transfer Line in the Linac Vault

R. Fliller et al.


Pulsed Magnet Lab Status• PML is developed to:

• Test concepts of pulsed systems• Build prototypes of critical pulsed systems• Test procured devices

• PML staff:• Senior scientist• Electrical engineer• Technician• Help from other NSLS-II/NSLS staff• Hiring experienced engineer

• Working on today:• Prototyping booster extraction kicker• Developing concept of a single PS for all SR

kickers• Testing high-voltage switches• Developing PML measurement and control

systems• PML is getting ready to receive SR

pulsed magnets for testing

S. Kowalski, R. Heese


Injector milestones

LFE delivery 22-Apr-11Linac delivery 12-Oct-11Linac installation begins 17-Oct-11Linac ready for commissioning 24-Jan-12 Booster FDR 4-Feb-11Booster delivery 7-Feb-12Booster installation complete 10-May-12Booster ready for commissioning 14-Aug-12 Injection straight Pulsed magnet contract award 22-Mar-11Pulsed magnet delivery 23-Apr-12Injection straight installation 15-Nov-12Injection straight testing 21-Feb-13

Storage Ring Technically Ready For Commissioning 2-May-13


Conclusions• Injector design is complete except for

• Transport line vacuum chambers and supports (detailed design)• Detailed designs of the injection straight components

• Number of new design features (booster beam stacking, DC/slow bump) has been implemented recently

• Components are now in manufacturing stage• Linac and booster contracts are with capable vendors• Procurement of the injection straight section pulsed magnets is in

preparation; Pulsed magnet laboratory is ready to receive pulsed magnet prototypes for testing

• Looking forward to availability of the injector building in May 2011


Working on injector

G. Wang, R. Fliller, J. Rose, R. Heese, G. Fries, B. Parker, F. Willeke, S. Ozaki, E. Johnson,

E. Weihreter, Y. Li, S. Kramer, I. Pinayev, M. Ferreira, R. Faussett, Y. Kawashima, M. Johansen, R. Alforque,

S. Krinsky, A.Blednykh, O. Dyling, R. Meier, S. Sharma, T. Mennona, B. Kosciuk, D. Hseuh, G. Ganetis, H. Ma, T. Shaftan, O. Singh, J. Skaritka, C. Spataro, E. Golnar,

C. Lavelle, P.K. Job, B. Casey, G. Woods


Injector Shielding

Out-of-Vacuum septum In-Vacuum septum

R. Alforque

• Injector shielding includes many supplemental shielding structures• in both transport lines• injection, extraction and shadow shielding in booster• around injection straight in the storage ring

nsls-ii injector status

Documents

storage ring current

rf cavities

rf frequency

gev3circulating current

complete rf system

beam lifetime

injector statust

beam dynamics analysis