| Paper | Title | Page |
|---|---|---|
| MOPTS100 | Transverse Emittance Measurement in the CERN Proton Synchrotron in View of Beam Production for the High-Luminosity LHC | 1106 |
| SUSPFO107 | use link to see paper's listing under its alternate paper code | |
|
||
| In the framework of the LHC Injectors Upgrade project the improvements required to achieve the parameters of the future beams for the High-Luminosity LHC are being studied and implemented. In order to deliver high brightness beams, control over the beam intensity and emittance is fundamental. Therefore, a highly accurate and reliable transverse emittance measurement is essential. Presently at the CERN Proton Synchrotron, the only operationally available emittance monitors not impacting the facility beam production are the flying wire scanners used to measure the circulating beam profile. The wire scanners will be replaced with a new generation in the next two years and a prototype is already installed. The prototype has been commissioned with beams featuring a wide range of intensities and emittances. This paper evaluates the performance of the prototype with respect to the present system via beam-based measurements. The transverse emittance measurement is discussed, considering the different potential error contributions to the measurement, such as knowledge of the machine optics and the dispersive contribution to the beam size. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPTS100 | |
| About • | paper received ※ 02 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| MOPTS101 | Study of the Transverse Emittance Blow-Up Along the Proton Synchrotron Booster Cycle During Wire Scanner Operation | 1110 |
|
||
| Transverse emittance measurements with wire scanners have been extensively studied across the accelerator complex at CERN due to their important role in characterizing the beam and their complicated modeling. In recent years, this topic has been of particular interest for the LHC Injectors Upgrade (LIU) project, where a tight transverse emittance blow-up budget between the Proton Synchrotron Booster (PSB) and the Proton Synchrotron (PS) is imposed to assure the required beam brightness for the High Luminosity LHC (HL-LHC). In order to maintain a high brightness beam, any source of emittance blow-up along the PSB cycle needs to be identified and mitigated. While wire scanners have been mostly used at extraction energy in the PSB, they can also operate along the energy cycle. The scattering of the protons with the wire increases considerably at lower energies, leading to an overestimation of the beam emittance. In this contribution we present the most recent studies, focusing on precisely quantifying the blow-up created by the flying wire with measurements in an optimized set-up and compared to FLUKA simulations. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPTS101 | |
| About • | paper received ※ 13 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEPMP025 | Matching Studies Between CERN PSB and PS Through Multi-Turn Beam Profile Acquisitions | 2367 |
|
||
| In the framework of the LHC Injectors Upgrade (LIU) project, the investigation and quantification of the optics mismatch between the CERN Proton Synchrotron Booster (PSB) and PS is a crucial step in understanding the source of horizontal emittance growth between the two machines. Extensive studies were carried out to estimate the mismatch from single-pass measurements in the transfer line and to rematch the transfer line to reduce the dispersive mismatch at PS injection while keeping the betatron matching unaltered. This paper presents the results of the data analysis of more recent multi-turn measurements, which profited from a new turn-by-turn beam profile monitor in the PS ring, to assess the achieved level of matching and corresponding emittance growth. The results confirm the improved matching and demonstrate the feasibility of the multi-turn technique as a fundamental tool that will be important for the recommissioning of the renovated transfer line after Long Shutdown 2. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP025 | |
| About • | paper received ※ 14 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEPMP026 | Emittance Dilution from the CERN Proton Synchrotron Booster’s Extraction Kickers | 2371 |
|
||
| Understanding the different sources of emittance dilution along the LHC injector chain is an important part of providing the high brightness proton beams demanded by the LHC Injectors Upgrade (LIU) project. In this context, the first beam-based measurements of the magnetic waveforms of the Proton Synchrotron Booster’s (PSB) extraction kickers were carried out and used to quantify the transverse emittance blow-up during extraction and transfer to the Proton Synchrotron (PS). In this contribution, the waveform measurement technique will be briefly outlined before the results and their implications for the LIU project and beam performance reach are discussed. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP026 | |
| About • | paper received ※ 14 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEPMP031 | SPS Slow Extraction Losses and Activation: Update on Recent Improvements | 2391 |
|
||
|
Annual high intensity requests of over 1019 protons on target (POT) from the CERN Super Proton Synchrotron (SPS) Fixed Target (FT) physics program continue, with the prospect of requests for even higher, unprecedented levels in the coming decade. A concerted and multifaceted R&D effort has been launched to understand and reduce the slow extraction induced radioactivation of the SPS and to anticipate future experimental proposals, such as SHiP* at the SPS Beam Dump Facility (BDF)**, which will request an additional 4·1019 POT per year. In this contribution, we report on operational improvements and recent advances that have been made to significantly reduce the slow extraction losses, by up to a factor of 3, with the deployment of new extraction concepts, including passive and active (thin, bent crystal) diffusers and extraction on the third-integer resonance with octupoles. In light of the successful tests of the prototype extraction loss reduction schemes, an outlook and implications for future SPS FT operation will be presented.
* A. Golutvin et al., Rep. CERN-SPSC-2015-016 (SPSC-P-350), CERN, Geneva, Switzerland, Apr. 2015. ** M. Lamont et al., Rep. CERN-PBC-REPORT-2018-001, CERN, Geneva, Switzerland, 11 Dec 2018. |
||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP031 | |
| About • | paper received ※ 14 May 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEPGW078 | Development and Test of a Beam Imaging System Based on Radiation Tolerant Optical Fiber Bundles | 2658 |
|
||
| Many of the beam image systems at CERN are located in high radiation environments. In order to cope with this issue, VIDICON cameras are presently used but their production has been nowadays discontinued worldwide. The development of an alternative beam imaging system is described here, based on radiation tolerant optical fibre bundles. Such an optical line relays the image of a scintillating screen to a standard CMOS camera, located away from the high radiation zone. A prototype system based on a 10m long bundle with 104 fibres has been tested in the TT2 transfer line at CERN. The light transmission is rather low, but is compensated by the sensitivity of the CMOS camera. The system had a field of view of 60 mm and a spatial resolution of ~1 mm. The radiation hardness of such a fiber bundle was tested at the IRMA-CEA facility in Saclay, France. The bundle was irradiated at a rate of 3.6 kGy/h for 8 consecutive day. The total integrated dose achieved was ~700 kGy, which corresponds to about ten years of operation at the beam imaging station with the highest radiation dose at CERN. While the light transmission was reduced by 50%, this is still adequate to provide acceptable images. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPGW078 | |
| About • | paper received ※ 10 May 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |