Author: Aberle, O.
Paper Title Page
MOPFI052 A New Lead Ion Injection System for the CERN SPS with 50 ns Rise Time 398
 
  • B. Goddard, O. Aberle, J. Borburgh, E. Carlier, K. Cornelis, L. Ducimetière, L.K. Jensen, T. Kramer, D. Manglunki, A. Mereghetti, V. Mertens, D. Nisbet, B. Salvant, L. Sermeus
    CERN, Geneva, Switzerland
  
  The LHC High Lu­mi­nos­ity up­grade pro­ject in­cludes a per­for­mance up­grade for heavy ions. One of the pre­sent per­for­mance lim­i­ta­tions is the rise time of the SPS in­jec­tion kicker sys­tem, which im­poses a spac­ing of at least 220 ns be­tween in­jected bunch trains at the op­er­a­tional rigid­ity. A re­duc­tion of this rise time to 50 ns for lead ions is re­quested as part of the suite of mea­sures needed to in­crease the pre­sent de­sign per­for­mance by a fac­tor three. A new in­jec­tion sys­tem based on a fast pulsed sep­tum and a fast kicker has been pro­posed to ful­fil this rise time re­quire­ment, and to meet all the con­straints as­so­ci­ated with the ex­ist­ing high in­ten­sity pro­ton in­jec­tion in the same re­gion. This paper de­scribes the con­cept and the re­quired equip­ment pa­ra­me­ters, and ex­plores the im­pli­ca­tions of such a sys­tem for SPS op­er­a­tion.  
 
MOPFI053 Upgrades of the SPS, Transfer Line and LHC Injection Protection Devices for the HL-LHC Era 401
 
  • Ö. Mete, O. Aberle, F. Cerutti, K. Cornelis, B. Goddard, V. Kain, R. Losito, F.L. Maciariello, M. Meddahi, A. Mereghetti, J.A. Uythoven, F.M. Velotti
    CERN, Geneva, Switzerland
  • E. Gianfelice-Wendt
    Fermilab, Batavia, USA
  
  The chal­leng­ing High Lu­mi­nos­ity LHC (HL-LHC) beam re­quire­ments will lead in the fu­ture to un­prece­dented beam pa­ra­me­ters along the LHC in­jec­tor chain. In the SPS ac­cel­er­a­tor these re­quests trans­late into about a fac­tor two higher in­ten­sity and bright­ness than the pre­sent de­sign per­for­mance. In ad­di­tion to the chal­lenge of pro­duc­ing and ac­cel­er­at­ing such beams, these pa­ra­me­ters af­fect the re­sis­tance of the ex­ist­ing equip­ment against beam im­pact. Most of the pro­tec­tion de­vices in the SPS ring, its trans­fer lines and the LHC in­jec­tion areas will be put under op­er­a­tional con­straints which are be­yond their de­sign spec­i­fi­ca­tion. The equip­ment con­cerned has been re­viewed and their re­sis­tance to the HL-LHC beams checked. The­o­ret­i­cal and sim­u­la­tion stud­ies have been per­formed for the SPS beam scrap­ing sys­tem, the pro­tec­tion de­vices and the dump ab­sorbers of the SPS-to-LHC trans­fer lines, as well as for the LHC in­jec­tion pro­tec­tion de­vices. The first re­sults of these stud­ies are re­ported, to­gether with the fu­ture prospects.  
 
MOPWO029 Remote Estimate of Collimator Jaw Damages with Sound Measurements during Beam Impacts 951
 
  • D. Deboy, O. Aberle, R.W. Aßmann, F. Carra, M. Cauchi, J. Lendaro, A. Masi, S. Redaelli
    CERN, Geneva, Switzerland
  
  Ir­reg­u­lar hits of high-in­ten­sity LHC beams on col­li­ma­tors can lead to se­vere dam­age of the col­li­ma­tor jaws. The iden­ti­fi­ca­tion of dam­aged col­li­ma­tor jaws by ob­ser­va­tion of beam mea­sure­ments is chal­leng­ing: on­line loss mea­sure­ments at the mo­ment of the im­pacts can be tricky and degra­da­tion of the over­all per­for­mance from sin­gle col­li­ma­tor dam­age can be dif­fi­cult to mea­sure. Vi­sual in­spec­tions are ex­cluded be­cause col­li­ma­tor jaws are en­closed in vac­uum tanks with­out win­dows. How­ever, the sound gen­er­ated dur­ing the beam im­pact can be used to give an es­ti­mate of the dam­age level. In 2012, high-in­ten­sity beam com­pa­ra­ble to a full nom­i­nal LHC bunch at 7 TeV was shot on a ter­tiary type LHC col­li­ma­tor at the Hi­Rad­Mat test fa­cil­ity at CERN. The paper pre­sents re­sults from sound record­ings of this ex­per­i­ment.  
 
MOPWO031 High Energy Beam Impact Tests on a LHC Tertiary Collimator at CERN HiRadMat Facility 954
 
  • M. Cauchi, O. Aberle, R.W. Aßmann, A. Bertarelli, F. Carra, A. Dallocchio, D. Deboy, L. Lari, S. Redaelli, A. Rossi
    CERN, Geneva, Switzerland
  • M. Cauchi, P. Mollicone
    UoM, Msida, Malta
  • L. Lari
    IFIC, Valencia, Spain
  • N.J. Sammut
    University of Malta, Information and Communication Technology, Msida, Malta
  
  The cor­rect func­tion­ing of the col­li­ma­tion sys­tem is cru­cial to safely op­er­ate the LHC. The re­quire­ments to han­dle high in­ten­sity beams can be de­mand­ing. In this re­spect, in­ves­ti­gat­ing the con­se­quences of LHC par­ti­cle beams hit­ting ter­tiary col­li­ma­tors (TCTs) in the ex­per­i­men­tal re­gions is a fun­da­men­tal issue for ma­chine pro­tec­tion. An ex­per­i­men­tal test was de­signed to in­ves­ti­gate the ro­bust­ness and ef­fects of beam ac­ci­dents on a fully as­sem­bled col­li­ma­tor, based on ac­ci­dent sce­nar­ios in the LHC. This ex­per­i­ment, car­ried out at the CERN Hi­Rad­Mat (High Ir­ra­di­a­tion to Ma­te­ri­als) fa­cil­ity, in­volved 440 GeV beam im­pacts of dif­fer­ent in­ten­si­ties on the jaws of a hor­i­zon­tal TCT. This paper pre­sents the ex­per­i­men­tal setup and the pre­lim­i­nary re­sults ob­tained to­gether with some first out­comes from vi­sual in­spec­tion.  
 
MOPWO034 Energy Deposition Studies for the Upgrade of the LHC Injection Lines 963
 
  • A. Mereghetti, O. Aberle, F. Cerutti, B. Goddard, V. Kain, F.L. Maciariello, M. Meddahi
    CERN, Geneva, Switzerland
  • R. Appleby
    UMAN, Manchester, United Kingdom
  • E. Gianfelice-Wendt
    Fermilab, Batavia, USA
  
  The LHC In­jec­tors Up­grade (LIU) Pro­ject aims at up­grad­ing the sys­tems in the LHC in­jec­tion chain, to re­li­ably de­liver the beams re­quired by the High-Lu­mi­nos­ity LHC (HL-LHC). Given the chal­leng­ing beam in­ten­si­ties and emit­tances, a re­view of the ex­ist­ing beam-in­ter­cept­ing de­vices is on-go­ing, in order to as­sess heat loads and con­se­quent thermo-me­chan­i­cal stresses. More­over, the ex­po­sure of down­stream el­e­ments to in­duced shower ra­di­a­tion is as­sessed. The study is in­tended to spot pos­si­ble is­sues and con­tribute to the de­f­i­n­i­tion of vi­able de­sign and lay­out so­lu­tions.  
 
TUPME032 Update on Beam Induced RF Heating in the LHC 1646
 
  • B. Salvant, O. Aberle, G. Arduini, R.W. Aßmann, V. Baglin, M.J. Barnes, W. Bartmann, P. Baudrenghien, O.E. Berrig, A. Bertarelli, C. Bracco, E. Bravin, G. Bregliozzi, R. Bruce, F. Carra, F. Caspers, G. Cattenoz, S.D. Claudet, H.A. Day, M. Deile, J.F. Esteban Müller, P. Fassnacht, M. Garlaschè, L. Gentini, B. Goddard, A. Grudiev, B. Henrist, S. Jakobsen, O.R. Jones, O. Kononenko, G. Lanza, L. Lari, T. Mastoridis, V. Mertens, N. Mounet, E. Métral, A.A. Nosych, J.L. Nougaret, S. Persichelli, A.M. Piguiet, S. Redaelli, F. Roncarolo, G. Rumolo, B. Salvachua, M. Sapinski, R. Schmidt, E.N. Shaposhnikova, L.J. Tavian, M.A. Timmins, J.A. Uythoven, A. Vidal, J. Wenninger, D. Wollmann, M. Zerlauth
    CERN, Geneva, Switzerland
  • H.A. Day
    UMAN, Manchester, United Kingdom
  • L. Lari
    IFIC, Valencia, Spain
  
  Since June 2011, the rapid in­crease of the lu­mi­nos­ity per­for­mance of the LHC has come at the ex­pense of in­creased tem­per­a­ture and pres­sure read­ings on spe­cific near-beam LHC equip­ment. In some cases, this beam in­duced heat­ing has caused de­lays whilie equip­ment cools down, beam dumps and even degra­da­tion of these de­vices. This con­tri­bu­tion gath­ers the ob­ser­va­tions of beam in­duced heat­ing at­trib­ut­able to beam cou­pling im­ped­ance, their cur­rent level of un­der­stand­ing and pos­si­ble ac­tions that are planned to be im­ple­mented dur­ing the long shut­down in 2013-2014.  
 
TUPWA042 Lessons Learned and Mitigation Measures for the CERN LHC Equipment with RF Fingers 1802
 
  • E. Métral, O. Aberle, R.W. Aßmann, V. Baglin, M.J. Barnes, O.E. Berrig, A. Bertarelli, G. Bregliozzi, S. Calatroni, F. Carra, F. Caspers, H.A. Day, M. Ferro-Luzzi, M.A. Gallilee, C. Garion, M. Garlaschè, A. Grudiev, J.M. Jimenez, O.R. Jones, O. Kononenko, R. Losito, J.L. Nougaret, V. Parma, S. Redaelli, B. Salvant, P.M. Strubin, R. Veness, C. Vollinger, W.J.M. Weterings
    CERN, Geneva, Switzerland
  
  Beam-in­duced RF heat­ing has been ob­served in sev­eral LHC com­po­nents when the bunch/beam in­ten­sity was in­creased and/or the bunch length re­duced. In par­tic­u­lar eight bel­lows, out of the ten dou­ble-bel­lows mod­ules pre­sent in the ma­chine in 2011, were found with the spring, which should keep the RF fin­gers in good elec­tri­cal con­tact with the cen­tral in­sert, bro­ken. Fol­low­ing these ob­ser­va­tions, the de­signs of all the com­po­nents of the LHC equipped with RF fin­gers have been re­viewed. The lessons learnt and mit­i­ga­tion mea­sures are pre­sented in this paper.  
 
THPEA041 Performance Improvements of the SPS Internal Beam Dump for the HL-LHC Beam 3231
 
  • F.M. Velotti, O. Aberle, C. Bracco, E. Carlier, P. Chiggiato, J.A. Ferreira Somoza, B. Goddard, M. Meddahi, V. Senaj, J.A. Uythoven
    CERN, Geneva, Switzerland
  
  The SPS in­ter­nal beam dump has been de­signed for beam spec­i­fi­ca­tions well below the HL-LHC ones, and for modes of op­er­a­tion which may not be ad­e­quate for the HL-LHC era. The pre­sent sys­tem suf­fers from sev­eral lim­i­ta­tions in the al­lowed in­ten­sity and en­ergy range, and its vac­uum per­for­mance af­fects nearby high-volt­age kicker sys­tems. In this re­port the lim­i­ta­tions of the in­ter­nal beam dump sys­tem are re­viewed, and the pos­si­ble im­prove­ments com­pared. Pre­lim­i­nary up­grade pro­pos­als are pre­sented, tak­ing into con­sid­er­a­tion the ex­pected op­er­a­tional HL-LHC pa­ra­me­ters.  
 
THPFI046 First Results of an Experiment on Advanced Collimator Materials at CERN HiRadMat Facility 3391
 
  • A. Bertarelli, O. Aberle, R.W. Aßmann, E. Berthomé, V. Boccone, M. Calderón Cueva, F. Carra, F. Cerutti, N. Charitonidis, C. Charrondière, A. Dallocchio, M. Donzé, P. Francon, M. Garlaschè, L. Gentini, M. Guinchard, N. Mariani, A. Masi, P. Moyret, S. Redaelli, A. Rossi, S.D.M. dos Santos
    CERN, Geneva, Switzerland
  • M. Calderón Cueva
    Universidad San Francisco de Quito, Cumbayá, Colombia
  • N. Charitonidis
    EPFL, Lausanne, Switzerland
  • L. Peroni, M. Scapin
    Politecnico di Torino, Torino, Italy
  
  Funding: The research leading to these results has received funding from the European Commission under the FP7 Research Infrastructures project EuCARD, grant agreement no. 227579
A com­pre­hen­sive, first-of-its-kind ex­per­i­ment (HRMT-14) has been re­cently car­ried out at CERN Hi­Rad­Mat fa­cil­ity on six dif­fer­ent ma­te­ri­als of in­ter­est for Beam In­ter­cept­ing De­vices (col­li­ma­tors, tar­gets, dumps). Both tra­di­tional ma­te­ri­als (Mo, W and Cu al­loys) as well as ad­vanced metal/di­a­mond and metal/graphite com­pos­ites were tested under ex­treme con­di­tions as to pres­sure, den­sity and tem­per­a­ture, lead­ing to the de­vel­op­ment of highly dy­namic phe­nom­ena as shock-waves, spal­la­tion, ex­plo­sions. Ex­per­i­men­tal data were ac­quired, mostly in real time, re­ly­ing on ex­ten­sive em­barked in­stru­men­ta­tion (strain gauges, tem­per­a­ture and vac­uum sen­sors) and on re­mote ac­qui­si­tion de­vices (laser Doppler vi­brom­e­ter and high speed cam­era). The ex­per­i­ment was a suc­cess under all points of view in spite of the tech­no­log­i­cal chal­lenges and harsh en­vi­ron­ment. First mea­sure­ments are in good agree­ment with re­sults of com­plex sim­u­la­tions, con­firm­ing the ef­fec­tive­ness of the ac­qui­si­tion sys­tem and the re­li­a­bil­ity of ad­vanced nu­mer­i­cal meth­ods when ma­te­r­ial con­sti­tu­tive mod­els are com­pletely avail­able. In­ter­est­ing in­for­ma­tion has been col­lected as to ther­mal shock ro­bust­ness of tested ma­te­ri­als. 		 
 
THPWO078 Status of the Upgrade of the CERN PS Booster 3939
 
  • K. Hanke, O. Aberle, M. E. Angoletta, W. Bartmann, S. Bartolome, E. Benedetto, C. Bertone, A. Blas, P. Bonnal, J. Borburgh, D. Bozzini, A.C. Butterworth, C. Carli, E. Carlier, J.R.T. Cole, P. Dahlen, M. Delonca, T. Dobers, A. Findlay, R. Froeschl, J. Hansen, D. Hay, S. Jensen, J.-M. Lacroix, P. Le Roux, L.A. Lopez Hernandez, C. Maglioni, A. Masi, G.W. Mason, S.J. Mathot, B. Mikulec, Y. Muttoni, A. Newborough, D. Nisbet, S. Olek, M.M. Paoluzzi, A. Perillo-Marcone, S. Pittet, B. Puccio, V. Raginel, B. Riffaud, I. Ruehl, A. Sarrió Martínez, J. Tan, B. Todd, V. Venturi, W.J.M. Weterings
    CERN, Geneva, Switzerland
  
  The CERN PS Booster (PSB) is presently un­der­go­ing an am­bi­tious con­sol­i­da­tion and up­grade pro­gram within the frame of the LHC In­jec­tors Up­grade (LIU) pro­ject. This pro­gram com­prises a new in­jec­tion scheme for H− ions from CERN’s new Linac4, the re­place­ment of the main RF sys­tems and an en­ergy up­grade of the PSB rings from 1.4 to 2.0 GeV which in­cludes the re­place­ment of the main mag­net power sup­ply as well as the up­grade of the ex­trac­tion equip­ment. This paper de­scribes the sta­tus and plans of this work pro­gram.