Waterfall diagram of Schottky spectra of a primary Uranium beam, heated with the help of a FRS (fragment separator) target.
First cooled with the broad acceptance ESR stochastic cooling system and subsequently cooled with the smaller acceptance electron cooler.
For the Collector Ring (CR) of the FAIR project, a 1–2 GHz stochastic cooling system is being developed to provide fast 3D cooling of hot secondary beams (anti-protons at 3 GeV and rare isotope ions at 740 MeV/u) at intensities up to 108 particles per cycle.
For antiproton cooling, cryogenic plunging Pick-Up electrodes will be used to improve the ratio of Schottky signals to thermal noise.
To cool hot rare isotope beams quickly, a two-stage cooling (pre-cooling by the Palmer method and main cooling by the notch filter method) has been decided.
This unique Stochastic Cooling System mainly consisting of two cryogenic plunging Slotline Pick-Ups, one Palmer Pick-Up, and two Slot-Ring Kickers is now under construction.[IPAC2023].
For pbar-cooling, the following special concepts have been adopted to improve the ratio of Schottky signals to thermal noises:
1) to keep the Pick-Up (PU) electrodes at 30–40 K;
2) to move the electrodes as the beam shrinks;
3) to implement the notch filter method for the longitudinal cooling for filtering out thermal noises.
Schematic of the verification setup of the finished Palmer pickup and the corresponding measurement results:
Shuntimpedance over the bandwidth for the beam on axis, Noise temperature over an extended bandwidth showing the effect of artificial cold loads.
Beam Measurements of a Palmer Pick-Up for the Collector Ring of FAIR
C. Peschke, R. Böhm, C. Dimopoulou, S. Wunderlich, C. Zhang
COOL 2023 Conference, Montreux, Switzerland, Download
A 1- 2 GHz Stochastic Cooling System for Antiprotons and Rare Isotopes
C. Zhang, A. Bardonner, R. Böhm, M. Bräscher, B. Breitkreutz, C. Dimopoulou, O. Gorda, R. Hettrich, J. Krieg, C. Peschke, A. Stuhl, S. Wunderlich, F. Esser, R. Greven, H. Schneider, R. Stassen
IPAC 2023 Conference, Venice, Italy
Suspended Ground Microstrip Coupled Slotline Electrode for Stochastic Cooling
S. Wunderlich and C. Peschke,
COOL 2021, Geneva, Switzerland.
EXPECTED PERFORMANCE OF THE STOCHASTIC COOLING AND RF SYSTEM IN THE COLLECTOR RING
O. Gorda, C. Dimopoulou, A. Dolinskii, T. Katayama
IPAC2018, Vancouver, BC, Canada
Stochastic Cooling Developments for the Collector Ring at FAIR
C. Dimopoulou, D. Barker, R. Böhm, R. Hettrich, W. Maier, C. Peschke, A. Stuhl,
S. Wunderlich, L. Thorndahl,
COOL 2015, Newport News, VA, USA
DOI:10.18429/JACoW-COOL2015-MOYAUD04
Stochastic Cooling Of Heavy Ions In The HESR
R. Stassen, B. Breitkreutz, G. Schug, H. Stockhorst
COOL 2015, Newport News, VA, USA
DOI:10.18429/JACoW-COOL2015-MOYAUD02
Stochastic Cooling in CR
F. Nolden
2nd MAC Meeting (2009), Egelsbach, Germany
Two PhD Studies are on-going
• Eduard Boos: Remodeling, improvement and future upgrade of the ESR stochastic cooling system: from software to hardware
• Stefan Wunderlich: Development of RF systems for stochastic cooling
One master study are on-going
• Lukas Fischer: Schadensanalyse und Optimierung von Wärmeleitbändern für die Strahlkühlung in einem Teilchenbeschleuniger
Feel free to contact us for possible doctoral or master theses.