HESR 2 Electron Cooling

Björn Gålnander

The Svedberg LaboratoryUppsala University

Midterm Review, DIRACsecondary-Beams

December 8, 2006

GSI, Darmstadt

Outline

• HESR Electron cooler

• Present project status

• Outlook

• Antiproton momentum, 1.5 –15 GeV/c

• Cooling to counteract PANDA pellet target

• Electron cooling up to 8.9 GeV/c(4.5 MeV electron energy)

• Stochastic cooling above 3.8 GeV/c

High Energy Storage RingHESR is presently being designed in a consortium formed between FZ-Jülich, GSI and UU

The electron cooler is the main responsibility of Uppsala University.

HESR Electron Cooler

e-beam parameters: HESR FermilabEnergy (MeV) 0.45 - 4.5 4.3Current (Amp) 1 0.5Solenoid field (T) 0.2 0.01Straightness (µrad rms) 10 200

The cooling force needs to be stronger than at Fermilab to counteract the internal target

• Higher magnetic field

• Better straightness

Parameters for the HESR cooler:

Objective of Design StudyTask 12, HESR 2: Electron cooling

Description of work:

An important part of the work will be to construct prototypes of several construct prototypes of several critical parts of the systemcritical parts of the system. The exact content of the prototyping work will be determined in the course of the study. The CELSIUS electron cooling CELSIUS electron cooling systemsystem, which will then be taken out of use for its purpose at the CELSIUS ring, will be used as a test benchwill be used as a test bench, and will be used to test electron beam diagnostic equipment as well as to make tests related to the high-voltage behaviour of the system.

Other aspects of the electron cooling system, including the method to charge the high-voltage terminal, the problems to create the requiredthe problems to create the required quality of the magnetic field and stability of the high voltagequality of the magnetic field and stability of the high voltage, the required ultra-high vacuum and the electron beam optics and stability of the electron beam transport will be investigated.will be investigated.

In the final reportfinal report all experience will be summarized, drawings will reflect the status of the component development, and a first design of a control system for this high power device will be suggested on the basis of the accumulated experience.

Present Project Plan

Different sub-projects, responsible persons

• Design high-voltage column G. Norman, A Shemyakin

• Test prototype high-voltage solenoid G. Norman

• Design magnet system for electron beam transport

K. Rathsman, D. Reistad

• Design and test magnet field measurement systemT. Bergmark

• Design vacuum chamber, make prototypeT. Bergmark, O. Byström

• Design and test prototype scraperB. Gålnander, T. Lofnes,

• Design electron gun and collectorG. Norman

• Tests on high-voltage regulation at Uppsala Tandem PelletronT. Bergmark

High Voltage Column

GunCollector

Pellet chain

HV solenoid

High voltage solenoid prototype

• Cover delivered

• Coils mounted and delivered Feb. 2007

• Sections of 3 metres (24 m total length)• Pancake coils (normal conducting), individually adjustable to achieve 10 μrad rms straightness

Magnet system

• Scraper and pick-up electrodes.

• Horizontal and vertical dipole windings.

Deliverable 29, Report on solenoids and toroids, delayed

• Design revised, making coils smaller and less expensive,

saving about 30 % of copper.

• Superconducting alternative is also considered

Measurement carriageand sensor head

• Prototypes are being manufactured

• Test will be performed during 2007

Magnetic Field Measurement System

needed for pancake alignment

Prototype test set-up

Carriage prototype

Vacuum Chambers

with rails for the Magnetic Field Measuring System

Test tube of 1 m, two sections of 2.8 m will be delivered week 5, 2007

Scraper tests at the CELSIUS coolerModification of CELSIUS cooler for scraper tests with electron beam

• Scraper prototype delivered next week

• Coils are being manufactured, delivered week 5, 2007

Outlook

• During spring 2007 several prototype tests will take place

• Autumn 2007, test evaluation and final report work

• No overall delay expected, HESR 2 will be finished by Feb. 2008.

• However, the Deliverable D29, “Report on solenoids and toroids”, is delayed until 1 March, 2007, since this sub-project has been given more weight compared to the original planning.

ID Task Name

1

2 Solenoids and toroids

3 design pancakes

4 design solenoids and toroids, including supports

5 D29 Report on solenoids and toroids

6 design correctors

7 design magnetic circuits

8 report on magnet system

9 preliminary design of high voltage tank

10

11 HV solenoid

12 design prototype HV solenoid

13 build prototype HV solenoid

14 mount HV solenoid test

15 perform HV solenoid tests

16 report on HV solenoid tests

17

18 Vacuum and neutralisation

19 prel. design vacuum chambers and clearing electrodes

20 understand neutralisation and vacuum

21 final design vacuum chambers and clearing electrodes

22

23 Magnetic measurement system

24 design tube and cart for m m system

25 build tube and cart for m. m. system

26 design prototype sensor head

27 build prototype sensor head

28 design and build optical and electronic system

29 design and build set-up for m. m. system

30 test prototype magnetic straightness measuring system

31 report on magnetic straightness measuring system

32

33

34 Diagnostics

35 design prototype scraper

36 build prototype scraper

37 test prototype scraper

38 design pick-up/scraper

39 build prototype pick-up/scraper

40

41 Test set-up for scraper

42 design changes in CELSIUS cooler for tests

43 build magnets/box/stands

44 make changes in CELSIUS cooler for tests

45 take CELSIUS cooler into operation

46

47 Gun and collector

48 design electron gun

49 design collector

50 Heat transfer calculations collector

51

52 HV regulation tests

53 make tests on hv regulation at Tandem Lab

54 discussions with Fermilab and NEC

55 report on hv regulation

56

57 final report

58 D32 (delivery of final report)

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr2006 2007 2008

Dag Reistad, Task Leader

Torsten Bergmark

Björn Gålnander, Deputy

Tomas Johnson

Tor Lofnes

Gunnar Norman

Olle Byström

Stefan Johnson

Tord Peterson

Karin Rathsman

Present group members

Collaboration with IKP (Ziemann, beam dynamics), MSL (Danared, magnetic field calculations), BINP Parkhomchuk et al., Fermilab, A. Shemyakin et al.

Thank you!

4.5 MeV tank

8 MeV tank

Layout