RUPAC-2016

 

INR High Intensity Proton Linac. Status and Prospects. TUZMH02

A. Feschenko, L.V. Kravchuk, V.L. Serov

       The sta­tus and the prospects of High In­ten­sity INR Linac are pre­sented. The rou­tine beam in­ten­sity is equal to 130 mkA. The an­nual ac­cel­er­a­tor run du­ra­tion is about 1600 hours. The main beam user fa­cil­i­ties are mul­ti­pur­pose com­plex for neu­tron sci­ence, iso­tope pro­duc­tion fa­cil­ity and pro­ton ther­apy fa­cil­ity. The pri­mary ac­tiv­i­ties are ac­cel­er­a­tor main­te­nance, mod­ern­iza­tion of ac­cel­er­a­tor sys­tems and beam trans­porta­tion chan­nels, in­creas­ing of ac­cel­er­a­tor re­li­a­bil­ity, im­prove­ment of beam pa­ra­me­ters.

Development of the INR Linear Accelerator DTL RF System. THXSH01

A.I. Kvasha, V.L. SerovA., A.V.Feschenko

      The reg­u­lar INR DTL RF sys­tem op­er­a­tion began in 1992. By this point three new type of vac­uum tube, de­signed pur­posely for INR lin­ear ac­cel­er­a­tor, were man­u­fac­tured at OKB "Swet­lana" in the amount suf­fi­cient for RF sys­tem op­er­a­tion dur­ing 20 years. Among them were two vac­uum tubes for final RF power am­pli­fier - GI-54A and RF dri­ver - GI-51A and also vac­uum tube for pow­er­ful anode mod­u­la­tor - GMI-44A. In the late 80s man­u­fac­ture of these vac­uum tubes was stopped and since 1990 de­sign­ing of new vac­uum tube for RF out­put power am­pli­fier in­stead of GI-54A was started. The new vac­uum tube GI-71A with out­put RF power up to 3 MW in pulse, plate power dis­si­pa­tion up to 120 kW and power gain about 10 was sim­pler and less ex­pen­sive in com­par­i­son with GI-54A. The tran­si­tion to new vac­uum tube began in 1999 and fin­ished in 2014. Suc­cess­ful test­ing of GI-57A as RF dri­ver, ful­filled in 2008, opened the pos­si­bil­ity of re­place­ment GI-51A. As for GMI-44A re­place­ment there are no ana­logues, pro­duced in Russ­ian fed­er­a­tion, and, as it turned out, the only op­tion was GI-71A again. Below some prob­lems, con­nected with the vac­uum tubes re­place­ment, as well as main re­sults of twenty years DTL RF sys­tem op­er­a­tion are con­sid­ered.

INR RAS Instrumentation for Bunch Shape and Beam Cross-Section Monitoring. THCBSH01

S.A. Gavrilov, A. Feschenko, P.I. Reinhardt-Nickoulin

       In­stru­ments for bunch shape and beam cross-sec­tion di­ag­nos­tics at ion linacs are as im­por­tant as com­pli­cated de­vices. Wide­spread Bunch Shape Mon­i­tors de­vel­oped in INR RAS are used dur­ing a linac com­mis­sion­ing and op­ti­miza­tion of beam dy­nam­ics. Beam Cross-Sec­tion Mon­i­tors im­ple­mented at INR RAS linac pro­vide ef­fi­cient non-de­struc­tive beam tun­ing and con­trol. Fea­tures of both mon­i­tors in­ves­ti­gated in sim­u­la­tions and beam tests are de­scribed. A va­ri­ety of ex­per­i­men­tal re­sults are pre­sented.

Proposal of the Accelerating Structure for the First Cavity of the Main Part of INR Linac. TUPSA004

I.V. Rybakov, A. Feschenko, Y.Z. Kalinin, L.V. Kravchuk, V.N. Leontiev, A.N. Naboka, V.V. Paramonov, V.L. Serov

       For the beam in­ten­sity and over­all sta­bil­ity im­prove­ment of INR linac re­place­ment of the first four sec­tion cav­ity of the main part is re­quired. The pre­sent cav­ity is re­al­ized as the Disks and Wash­ers (DAW) struc­ture. The new cav­ity should not lose to the pre­sent one in elec­tro dy­nam­i­cal pa­ra­me­ters with min­i­mal mod­i­fi­ca­tions in the rest linac sys­tems. As the pos­si­ble struc­tures for the first cav­ity re­place­ment both proven in ex­ploita­tion struc­tures and promis­ing de­vel­op­ments were con­sid­ered. The analy­sis of elec­tro dy­nam­i­cal pa­ra­me­ters, cou­pled RF heat­ing, me­chan­i­cal processes and man­u­fac­tur­ing analy­sis were per­formed for the con­sid­ered struc­tures. For fur­ther de­vel­op­ment the Cut Disk Struc­ture (CDS) op­tion is pro­posed as the struc­ture with sat­is­fy­ing RF pa­ra­me­ters and hav­ing the small­est trans­verse

di­men­sions in com­par­i­son with ana­logues. For the pro­duc­tion sim­pli­fi­ca­tion with min­i­mal losses in elec­tro dy­nam­i­cal pa­ra­me­ters an uni­fi­ca­tion of the main geo­met­ri­cal pa­ra­me­ters for the four sec­tions cells was per­formed. The pos­si­bil­ity of mul­ti­paction in the cav­ity is con­sid­ered and an op­tion for its damp­ing is pro­posed. The man­u­fac­tur­ing tol­er­ances for the struc­ture are es­ti­mated.

Electrodynamic Characteristics of RF-Deflector for Bunch Shape Monitor. THPSC055

A. Feschenko, S.A. Gavrilov, D.A. Chermoshentsev

        Bunch shape mon­i­tors, based on a trans­verse RF-scan­ning of sec­ondary elec­trons, are used for mea­sure­ments of par­ti­cles lon­gi­tu­di­nal dis­tri­b­u­tion in bunches at dif­fer­ent lin­ear ion ac­cel­er­a­tors. The phase res­o­lu­tion of such mon­i­tors de­pends cru­cially on ac­cu­racy of fab­ri­ca­tion and tun­ing of RF-de­flec­tor, thus pre­lim­i­nary sim­u­la­tions of its elec­tro­dy­namic char­ac­ter­is­tics are of im­por­tance for sub­se­quent com­mis­sion­ing of the mon­i­tor. Sim­u­la­tions of some basic op­er­a­tional elec­tro­dy­namic pa­ra­me­ters and re­sults of ex­per­i­men­tal mea­sure­ments are pre­sented.

Proposal of the Accelerating Structure for the First Cavity of the Main Part of INR Linac. TUPSA004

I.V. Rybakov, A. Feschenko, Y.Z. Kalinin, L.V. Kravchuk, V.N. Leontiev, A.N. Naboka, V.V. Paramonov, V.L. Serov

         For the beam in­ten­sity and over­all sta­bil­ity im­prove­ment of INR linac re­place­ment of the first four sec­tion cav­ity of the main part is re­quired. The pre­sent cav­ity is re­al­ized as the Disks and Wash­ers (DAW) struc­ture. The new cav­ity should not lose to the pre­sent one in elec­tro dy­nam­i­cal pa­ra­me­ters with min­i­mal mod­i­fi­ca­tions in the rest linac sys­tems. As the pos­si­ble struc­tures for the first cav­ity re­place­ment both proven in ex­ploita­tion struc­tures and promis­ing de­vel­op­ments were con­sid­ered. The analy­sis of elec­tro dy­nam­i­cal pa­ra­me­ters, cou­pled RF heat­ing, me­chan­i­cal processes and man­u­fac­tur­ing analy­sis were per­formed for the con­sid­ered struc­tures. For fur­ther de­vel­op­ment the Cut Disk Struc­ture (CDS) op­tion is pro­posed as the struc­ture with sat­is­fy­ing RF pa­ra­me­ters and hav­ing the small­est trans­verse di­men­sions in com­par­i­son with ana­logues. For the pro­duc­tion sim­pli­fi­ca­tion with min­i­mal losses in elec­tro dy­nam­i­cal pa­ra­me­ters an uni­fi­ca­tion of the main geo­met­ri­cal pa­ra­me­ters for the four sec­tions cells was per­formed. The pos­si­bil­ity of mul­ti­paction in the cav­ity is con­sid­ered and an op­tion for its damp­ing is pro­posed. The man­u­fac­tur­ing tol­er­ances for the struc­ture are es­ti­mated.

The Pepper-Pot Emittance Measuring Device at the 400 keV H-minus LEBT Channel.  THPSC053

V.S. Klenov, S. Bragin, O.T. Frolov, S.E. Golubovski, O.V. Grekhov, O. Volodkevich, V. Zubets

         The emit­tance mea­sur­ing de­vice has been de­vel­oped for op­er­a­tional con­trol of INR RAS linac 400 keV H-mi­nus in­jec­tor beam pa­ra­me­ters. It in­cludes the "pep­per-pot", the quartz screen, the CCD cam­era, PC, the soft­ware for cam­era data pro­cess­ing and beam phase por­trait for­ma­tion. The de­vice has been mounted at the first straight sec­tion ex­ten­sion of H-mi­nus LEBT after 45 de­gree bend­ing mag­net. When the bend­ing mag­net is switched off the de­vice is pos­si­ble to mea­sure and to rep­re­sent sin­gle shot beam phase por­trait. The re­sults of the H-mi­nus beam emit­tance mea­sure­ments and the de­vice per­for­mance have been dis­cussed.

Power Supplies for IHEP Negative Hydrogen Ions Source.  THPSC031

B.A. Frolov, V.S. Klenov, V. Zubets

         The source of neg­a­tive hy­dro­gen ions is con­structed at IHEP for the im­ple­men­ta­tion of mul­ti­turn charge-ex­change in­jec­tion to in­crease the in­ten­sity of IHEP buster. Sur­face-plasma ion souce (SPS) with Pen­ning dis­charge is se­lected as a source of H-mi­nus ions. A set of power sup­plies for SPS, which in­cludes the ex­trac­tion volt­age power sup­ply, the dis­charge power sup­plies, the hy­dro­gen gas pulse valve power sup­ply, ce­sium oven and ce­sium stor­age de­vice tem­per­a­ture con­trollers, was de­signed, con­structed and tested on the equiv­a­lent loads. This set of power sup­plies will al­lows for com­mis­sion­ing and test­ing the ion source with the beam ex­trac­tion en­ergy up to 25 keV and rep­e­ti­tion rate 25 Hz.

Status of the Nuclotron. FRCAMH01

A.O. Sidorin č äš. (Äóįķą), A. Belov (ČßČ ŠĄĶ)

         Since last RuPAC two runs of the Nu­clotron op­er­a­tion were per­formed: in Jan­u­ary - March of 2015 and June 2016. Presently we are pro­vid­ing the run, which has been started at the end of Oc­to­ber and will be con­tin­ued up to the end of De­cem­ber. The fa­cil­ity de­vel­op­ment is aimed to the per­for­mance in­crease for cur­rent phys­i­cal pro­gram re­al­iza­tion and prepa­ra­tion to the NICA Booster con­struc­tion and Bary­onic Mat­ter at Nu­clotron ex­per­i­ment.

Commissioning of New Light Ion RFQ Linac and First Nuclotron Run with New Injector. FRCAMH02

A.V. Butenko č äš. (Äóįķą), A. Belov (ČßČ ŠĄĶ)

         The new ac­cel­er­a­tor com­plex Nu­clotron-based Ion Col­lider fA­cil­ity (NICA) is now under de­vel­op­ment and con­struc­tion at JINR, Dubna. This com­plex is as­sumed to op­er­ate using two in­jec­tors: the Al­varez-type linac LU-20 as in­jec­tor of light ions, po­lar­ized pro­tons and deuterons and a new linac HILAc - in­jec­tor of heavy ions beams. Old HV for-in­jec­tor of the LU-20, which op­er­ated from 1974, is re­placed by the new RFQ ac­cel­er­a­tor, which was com­mis­sioned in spring 2016. The first Nu­clotron tech­no­log­i­cal run with new fore-in­jec­tor was per­formed in June 2016. Beams of D+ and H2+ were suc­cess­fully in­jected and ac­cel­er­ated in the Nu­clotron ring. Main re­sults of the RFQ com­mis­sion­ing and the first Nu­clotron run with new for-in­jec­tor is dis­cussed in this paper.