Keyword: brightness
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MOPAB059 Energy Chirp Measurements by Means of an RF Deflector: a Case Study the Gamma Beam Source LINAC at ELI-NP electron, linac, detector, simulation 242
 
  • L. Sabato
    U. Sannio, Benevento, Italy
  • P. Arpaia, A. Liccardo
    Naples University Federico II, Science and Technology Pole, Napoli, Italy
  • A. Mostacci, L. Palumbo
    University of Rome La Sapienza, Rome, Italy
  • A. Variola
    INFN/LNF, Frascati (Roma), Italy
  
  RF De­flec­tor (RFD) based mea­sure­ments are widely used in high–bright­ness elec­tron LINAC around the world in order to mea­sure the ultra–short elec­tron bunch length. The RFD pro­vides a ver­ti­cal kick to the par­ti­cles of the elec­tron bunch ac­cord­ing to their lon­gi­tu­di­nal po­si­tions. In this paper, a mea­sure­ment tech­nique for the bunch length and other bunch pro­pri­eties, based on the usage of an RFD, is pro­posed. The basic idea is to ob­tain in­for­ma­tion about the bunch length, en­ergy chirp, and en­ergy spread from ver­ti­cal spot size mea­sure­ments vary­ing the RFD phase, be­cause they add con­tri­bu­tions on this quan­tity. The case study is the Gamma Beam Sys­tem (GBS), the Comp­ton Source being built in the Ex­treme Light In­fra­struc­ture–Nu­clear Physics (ELI–NP) fa­cil­ity. The ELEc­tron Gen­er­a­tion ANd Track­ing (EL­E­GANT) code is used for track­ing the par­ti­cles from RFD to the mea­sure­ment screen.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB059  
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MOPIK011 Electron Beam Generation From InGaN/GaN Superlattice Photocathode electron, laser, polarization, gun 522
 
  • N. Yamamoto
    KEK, Ibaraki, Japan
  • M. Hosaka, A. Mano, T. Miyauchi, Y. Takashima
    Nagoya University, Nagoya, Japan
  • M. Katoh
    UVSOR, Okazaki, Japan
  
  GaAs-type pho­to­cath­ode (PC) has been used as elec­tron spin po­lar­iza­tion (ESP) sources for var­i­ous ap­pli­ca­tions. Re­cently, by using a strain-com­pen­sated tech­nique for GaAs/GaAsP, the super lat­tice (SL) thick­ness of up to 720 nm could be man­u­fac­tured and the quan­tum ef­fi­ciency (QE) im­prove­ments with the thick­ness in­creases was ob­served. In the ex­per­i­ments, the ESP degra­da­tion was also ob­served for the thicker thick­ness sam­ples than 194nm and we con­sid­ered that elec­tron spin re­lax­ation dur­ing dif­fu­sion process in the PC caused the degra­da­tion. There­fore, we pro­pose de­vel­op­ing fcc-GaN based PCs in­stead of GaAs be­cause a fac­tor of ten longer spin re­lax­ation time com­pared with GaAs/GaAsP SL was re­ported. How­ever an fcc-GaN sam­ple with ad­e­quate di­men­sions for PC ap­pli­ca­tions is not avail­able at pre­sent due to man­u­fac­tur­ing dif­fi­cul­ties. Then at the start of GaN-type PC de­vel­op­ment, an hcp-GaN sam­ple has been stud­ied. In the study, NEA-ac­ti­va­tion was made for an InGaN/GaN SL sam­ple and QE, sur­face life­time and ESP were mea­sured. The QE and ESP val­ues were 1.3% and 2.1% at the pump laser wave­length of 405nm.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK011  
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MOPIK019 Upgrade Options Towards Higher Fields and Beam Energies for Continuous-Wave Room-Temperature VHF RF Guns gun, electron, cathode, cavity 542
 
  • F. Sannibale, J.M. Byrd, D. Filippetto, M.J. Johnson, D. Li, T.H. Luo, C.E. Mitchell, J.W. Staples, S.P. Virostek
    LBNL, Berkeley, California, USA
  
  Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231
Sci­ence de­mand for MHz-class rep­e­ti­tion rate elec­tron beam ap­pli­ca­tions such as free elec­tron lasers (FELs), in­verse Comp­ton scat­ter­ing sources, and ul­tra­fast elec­tron dif­frac­tion and mi­croscopy (UED/UEM), pushed the de­vel­op­ment of new gun schemes that could gen­er­ate high bright­ness beams at such high rates. At the Lawrence Berke­ley Lab (LBNL), we pro­posed a new con­cept room-tem­per­a­ture RF gun res­onat­ing in the VHF fre­quency range (30-300 MHz) ca­pa­ble of op­er­at­ing in con­tin­u­ous wave mode at the fields re­quired for high-bright­ness per­for­mance. A first VHF-Gun was con­structed and tested in the APEX fa­cil­ity at LBNL, which suc­cess­fully demon­strated all de­sign pa­ra­me­ters and the gen­er­a­tion of high bright­ness elec­tron beams. A sec­ond ver­sion of the APEX VHF-Gun is being built at LBNL for the LCLS-II, the new SLAC X-ray FEL. Re­cent stud­ies showed that a pro­posed LCLS-II up­grade and UED/UEM ap­pli­ca­tions would greatly ben­e­fit from an in­creased gun bright­ness ob­tained by rais­ing the elec­tric field at the cath­ode and the beam en­ergy at the gun exit. In this paper, we pre­sent and dis­cuss pos­si­ble up­grade op­tions that would allow ex­ten­sion of the VHF-Gun per­for­mance to­wards these new goals. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK019  
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MOPVA002 Initial Stage of Self Amplified Radiation Emission From Electron Bunches in Crystal: Linear Response Theory radiation, electron, polarization, undulator 848
 
  • A.I. Benediktovitch, I. Lobach
    BSU, Minsk, Belarus, Belarus
  
  Self am­pli­fied spon­ta­neous emis­sion (SASE) is a key process in X-ray free elec­tron lasers' op­er­a­tion. In this case the spon­ta­neous emis­sion is un­du­la­tor ra­di­a­tion emis­sion, the ra­di­a­tion in X-ray range being pos­si­ble from elec­trons in GeV en­ergy range. In the case of in­ter­ac­tion of elec­trons with prop­erly aligned crys­tal the chan­nel­ing ra­di­a­tion re­sults in X-rays from elec­trons with en­er­gies in tens MeV en­ergy range. In this sit­u­a­tion for high cur­rent den­si­ties the SASE process may take place that po­ten­tially could lead to con­struc­tion of a com­pact bright X-ray source. In pre­sent con­tri­bu­tion the first prin­ci­ple the­o­ret­i­cal de­scrip­tion is out­lined and first order per­tur­ba­tion the­ory is used to model the ini­tial stage of SASE. The tran­si­tion from spon­ta­neous to SASE regime is de­scribed, the re­quire­ments for bunch cur­rent and emit­tance are de­ter­mined. By means of dis­per­sion equa­tion analy­sis and bound­ary con­di­tion ap­pli­ca­tion the in­ten­sity ra­di­ated from crys­tal slab is cal­cu­lated and it is shown that Bragg dif­frac­tion could en­hance self am­pli­fi­ca­tion. A nu­mer­i­cal ex­am­ple for Si (001) il­lus­trates the model.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA002  
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TUPAB055 Development of compact magnetic field measurement system available for in-vacuum undulators undulator, vacuum, emittance, photon 1449
 
  • M. Adachi, R. Kato, T. Shioya, K. Tsuchiya
    KEK, Ibaraki, Japan
  
  A low-emit­tance 3-GeV KEK-LS* ring has been de­signed at KEK. KEK-LS's un­du­la­tors can pro­duce ex­tremely high bright­ness light rang­ing from VUV to X-ray. Bright­ness of un­du­la­tor light strongly de­pends on the phase error of its pe­ri­odic mag­netic field. Then a pre­cise mag­netic field ad­just­ment is re­quired in order to pre­vent the re­duc­tion of the bright­ness per­for­mance. Gen­er­ally, the ad­just­ment is per­formed by the con­ven­tional field mea­sure­ment sys­tem equipped with hole-probes on a huge stone table. But, for the in-vac­uum un­du­la­tor, the mea­sure­ment must be per­formed with­out the vac­uum cham­ber. The ad­di­tional phase error caused by reat­tach­ing the cham­ber is not neg­li­gi­ble for the low emit­tance rings. There­fore, some groups have de­vel­oped mea­sure­ment sys­tems avail­able for the di­rect field mea­sure­ment in­side the cham­ber**,***. We have started to de­velop a com­pact mea­sure­ment sys­tem. Our sys­tem is com­pacted and sta­bi­lized by uti­liz­ing the rigid metal beam of the un­du­la­tor frame in­stead of the stone table. In the con­fer­ence, we will re­port the de­tail of the sys­tem and the pre­sent sta­tus of the de­vel­op­ment.
* KEK-LS HP, http://kekls.kek.jp/
** T. Tanaka, et al., Physical Review ST-AB, vol.12, p.120702 (2009).
*** M. Musardo, et al., Proceedings of IPAC2015, Richmond, VA, USA, p.1693 (2015). 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPAB055  
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TUPAB129 Optimization of Beam Dynamics for an S-Band Ultra-High Gradient Photoinjector gun, electron, emittance, cathode 1626
 
  • A.D. Cahill, A. Fukasawa, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • C. Limborg, W. Qin
    SLAC, Menlo Park, California, USA
  
  Funding: Work Supported by DOE/SU Contract DE-AC02-76-SF00515, US NSF Award PHY-1549132, the Center for Bright Beams, and DOE SCGSR Fellowship. Travel to IPAC'17 supported by the Div. of Phys. of the US NSF (Accel. Sci. Prog.) and the Div. of Beam Phys. of the APS
New elec­tron sources with im­proved bright­ness are de­sired to en­hance the ca­pa­bil­i­ties of FELs, mak­ing them more com­pact and fully co­her­ent. Im­prove­ments in elec­tron source bright­ness can be achieved by in­creas­ing elec­tric fields on the cath­ode of photo-emit­ted elec­tron guns. Re­cent de­vel­op­ments in pulsed RF ac­cel­er­a­tor struc­tures show that very high gra­di­ent fields can be sus­tained with low break­down rates by op­er­at­ing at cryo-tem­per­a­tures, which when ap­plied to pho­to­guns will lead to a large in­crease in the elec­tron beam bright­ness. In par­tic­u­lar, our sim­u­la­tions show that when op­er­at­ing with a peak gra­di­ent field of 240 MV/m on the cath­ode of an S-band, elec­tron beam bright­ness of 80~nC/(mm· mrad)2/mm can be achieved with 100~pC bunches. In this paper, we pre­sent the de­sign and op­ti­miza­tion of an 1.x cell S-Band RF pho­toin­jec­tor, where the x varies from 4-6. The op­ti­miza­tion in bright­ness has been ob­tained by using a multi-ob­jec­tive ge­netic al­go­rithm on the so­lu­tions cal­cu­lated with the ASTRA code. We cal­cu­late the op­ti­mum length of the rf gun, po­si­tion of ac­cel­er­at­ing struc­ture, and laser pulse di­men­sions for a va­ri­ety of charges. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPAB129  
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TUPIK068 Parameters Calibration and Compensation-Rematch of Failure Cavities in CADS Injector cavity, simulation, experiment, rfq 1852
 
  • Y.Z. Jia, W.L. Chen, W.P. Dou, P.H. Gao, H. Jia, S.H. Liu, Y.S. Qin, C. Wang, W.S. Wang, Z.J. Wang
    IMP/CAS, Lanzhou, People's Republic of China
  
  Now when a fail­ure on the China Ac­cel­er­a­tor Dri­ven Sys­tem (CADS) is de­tected, the beam will be stopped by the ma­chine pro­tec­tion sys­tem (MPS) im­me­di­ately. But be­cause of the de­mand of the beam trip (more than 5 min) rate which should be less than 50 times per year [1], it is im­por­tant to avoid cut­ting beam down or re­cover the beam in a short time. The com­pen­sa­tion and re­match is of great im­por­tance. If the fail­ure is on a cav­ity, the other cav­i­ties should re­tune to com­pen­sate the beam en­ergy, po­si­tion and phase in order to re­cover the beam in short time de­pend­ing on the time of on­line cal­cu­la­tion.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK068  
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TUPVA029 Observations of Emittance Growth in the Presence of External Noise in the LHC emittance, simulation, damping, experiment 2117
 
  • X. Buffat, C. Tambasco, D. Valuch
    CERN, Geneva, Switzerland
  • J. Barranco García, T. Pieloni, C. Tambasco
    EPFL, Lausanne, Switzerland
  
  Ded­i­cated ex­per­i­ments were per­fomed in the LHC to study the im­pact of noise on col­lid­ing high bright­ness beams. The re­sults are com­pared to the­o­ret­i­cal mod­els and mul­ti­par­ti­cle track­ing sim­u­la­tions. The im­pacts on the LHC op­er­a­tion and the HL-LHC pro­ject are dis­cussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA029  
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WEOBB3 Advancement of an Accelerator-Driven High-Brightness Source for Fast Neutron Imaging neutron, target, dipole, quadrupole 2533
 
  • B. Rusnak, O. Alford, G.G. Anderson, S.G. Anderson, D.L. Bleuel, J.A. Caggiano, M.L. Crank, S.E. Fisher, P. Fitsos, D.J. Gibson, M. Hall, D.J. Jamero, M.S. Johnson, L. Kruse, K.S. Lange, R.A. Marsh, D. P. Nielsen, J.D. Sain, R. Souza, A. Wiedrick
    LLNL, Livermore, California, USA
  
  Funding: This work performed under the auspices of the U. S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.
Lawrence Liv­er­more Na­tional Lab (LLNL) is build­ing an in­tense, high-bright­ness fast neu­tron source to cre­ate mil­lime­ter-scale neu­tron ra­di­ographs and im­ages. An in­tense source (1011 n/s/sr at 0 de­grees) of fast neu­trons (10 MeV) al­lows for pen­e­trat­ing very thick, dense ob­jects while pre­serv­ing the abil­ity to cre­ate good image con­trast in low den­sity fea­tures within the ob­ject and main­tain­ing high de­tec­tor re­sponse ef­fi­ciency. Fast neu­trons will be pro­duced using a pulsed 7 MeV, 300 mi­croamp av­er­age-cur­rent com­mer­cial ion ac­cel­er­a­tor that will de­liver deuteron bunches to a 3 at­mos­phere deu­terium gas cell tar­get to pro­duce neu­trons by the D(d, n)3He re­ac­tion. Due to the high power den­sity of such a tightly fo­cused, mod­est-en­ergy ion beam, the trans­port, con­trols, di­ag­nos­tics, and in par­tic­u­lar the neu­tron pro­duc­tion gas tar­get and beam stop ap­proaches pre­sent sig­nif­i­cant en­gi­neer­ing chal­lenges. Progress and sta­tus on the build­ing and early com­mis­sion­ing of the lab-scale demon­stra­tion ma­chine shall be pre­sented. 		 
slides icon Slides WEOBB3 [2.654 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEOBB3  
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WEPAB002 Pushing the MAX IV 3 GeV Storage Ring Brightness and Coherence Towards the Limit of its Magnetic Lattice optics, lattice, storage-ring, emittance 2557
 
  • S.C. Leemann
    MAX IV Laboratory, Lund University, Lund, Sweden
  • W.A. Wurtz
    CLS, Saskatoon, Saskatchewan, Canada
  
  The MAX IV 3 GeV stor­age ring is presently being com­mis­sioned and cru­cial pa­ra­me­ters such as ma­chine func­tions, emit­tance, and stored cur­rent have ei­ther al­ready been reached or are ap­proach­ing their de­sign spec­i­fi­ca­tions*. Once the base­line per­for­mance has been achieved, a cam­paign will be launched to fur­ther im­prove the bright­ness and co­her­ence of this stor­age ring for typ­i­cal x-ray users. Dur­ing re­cent years, sev­eral such im­prove­ments have been de­signed**. Com­mon to these ap­proaches is that they at­tempt to im­prove the stor­age ring per­for­mance using ex­ist­ing hard­ware pro­vided for the base­line de­sign. Such im­prove­ments there­fore pre­sent more short-term up­grades. In this paper, how­ever, we in­ves­ti­gate medium-term im­prove­ments as­sum­ing power sup­plies can be ex­changed in an at­tempt to push the bright­ness and co­her­ence of the stor­age ring to the limit of what can be achieved with­out ex­chang­ing the mag­netic lat­tice it­self. We out­line op­tics re­quire­ments, the op­tics op­ti­miza­tion process, and sum­ma­rize achiev­able pa­ra­me­ters.
* WEPAB075 & WEPAB076 at IPAC17
** MOPHO05 at PAC2013, TUPRI026 at IPAC'4, PRAB 19 060701 (2016)
 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB002  
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WEPAB023 First Operation of a Harmonic Lasing Self-Seeded FEL FEL, undulator, electron, operation 2621
 
  • E. Schneidmiller, B. Faatz, M. Kuhlmann, J. Rönsch-Schulenburg, S. Schreiber, M. Tischer, M.V. Yurkov
    DESY, Hamburg, Germany
  
  Har­monic las­ing is a per­spec­tive mode of op­er­a­tion of X-ray FEL user fa­cil­i­ties that al­lows to pro­vide bril­liant beams of higher en­ergy pho­tons for user ex­per­i­ments. An­other use­ful ap­pli­ca­tion of har­monic las­ing is so called Har­monic Las­ing Self-Seeded Free Elec­tron Laser (HLSS FEL) that al­lows to im­prove spec­tral bright­ness of these fa­cil­i­ties. In the past, har­monic las­ing has been demon­strated in the FEL os­cil­la­tors in in­frared and vis­i­ble wave­length ranges, but not in high-gain FELs and not at short wave­lengths. In this paper we re­port on the first ev­i­dence of the har­monic las­ing and the first op­er­a­tion of the HLSS FEL at the soft X-ray FEL user fa­cil­ity FLASH in the wave­length range be­tween 4.5 nm and 15 nm. Spec­tral bright­ness was im­proved in com­par­i­son with Self-Am­pli­fied Spon­ta­neous emis­sion (SASE) FEL by a fac­tor of six in the ex­po­nen­tial gain regime. A bet­ter per­for­mance of HLSS FEL with re­spect to SASE FEL in the post-sat­u­ra­tion regime with a ta­pered un­du­la­tor was ob­served as well. The first demon­stra­tion of har­monic las­ing in a high-gain FEL and at a short wave­length paves the way for a va­ri­ety of ap­pli­ca­tions of this new op­er­a­tion mode in X-ray FELs.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB023  
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WEPAB047 Concept of a New Generation Synchrotron Radiation Facility KEK Light Source lattice, undulator, cavity, emittance 2687
 
  • T. Honda
    KEK, Ibaraki, Japan
  
  KEK has pro­posed a new SR fa­cil­ity: KEK Light Source (KEK-LS) to­wards the com­ple­tion of the first half of the 2020s. The en­ergy and the nat­ural hor­i­zon­tal emit­tance are 3 GeV and 0.13 nm rad, re­spec­tively. To mit­i­gate the in­tra-beam scat­ter­ing ef­fect, we are plan­ning to in­stall third har­monic RF cav­i­ties. The ex­tremely low emit­tance ring has been de­signed based on the Hy­brid Multi-Bend Achro­matic (HMBA) lat­tice, which was orig­i­nally de­vel­oped at the ESRF up­grade pro­ject. We have mod­i­fied it to in­sert a short straight sec­tion at the cen­ter of the unit cell. The num­ber of unit cells is 20, and the cir­cum­fer­ence is about 570 m. Ex­cept for an RF sec­tion and an in­jec­tion sec­tion, the ring can ac­com­mo­date 18 un­du­la­tors in the long straight sec­tions of 5.6 m, and the ad­di­tional 20 short straight sec­tion of 1.2 m will be used for short-pe­riod nar­row-gap un­du­la­tors. If we as­sume an un­du­la­tor of the mag­netic pe­riod 20 mm, total length 5.0 m, and the small­est gap 4 mm, the SR bright­ness ap­proaches 1022 Pho­tons/mrad2/mm2/s/0.1%B.W. at the X-ray range. It has a high co­her­ent frac­tion of about 20% at the dif­frac­tion limit wave­length 0.32 keV.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB047  
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WEPAB054 Candidate HEPS Lattice Design With Emittances Approaching the Diffraction Limit of Hard X-Rays lattice, emittance, dipole, storage-ring 2703
 
  • Y. Jiao, S.Y. Chen, G. Xu
    IHEP, Beijing, People's Republic of China
  
  Funding: Work supported by NSFC (11475202, 11405187)
The High En­ergy Pho­ton Source is a 6-GeV, kilo­me­tre-scale stor­age ring light source to be built in Bei­jing. A lat­tice of the stor­age ring was pro­posed, con­sist­ing of 48 hy­brid 7BAs, and hav­ing a nat­ural emit­tance of 60 pm and a cir­cum­fer­ence of ~1.3 km. In this paper, we dis­cuss the pos­si­bil­ity of fur­ther re­duc­ing the emit­tance to ap­proach the dif­frac­tion limit of hard X-ray with 'typ­i­cal' wave­length of 1 Å. We in­tro­duce the con­sid­er­a­tions on the choice of lat­tice struc­ture and cir­cum­fer­ence, and con­crete lat­tice de­signs. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB054  
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WEPAB098 Dielectrically-Loaded Waveguide as a Microwave Undulator for High Brillance X-Rays at 45 - 90 Kev undulator, photon, operation, coupling 2812
 
  • R. Kustom, A. Nassiri, G.J. Waldschmidt
    ANL, Argonne, Illinois, USA
  
  The HEM12 mode in a cylin­dri­cal, di­elec­tri­cally-loaded wave­guide pro­vides E and H fields on the cen­tral axis that are sig­nif­i­cantly higher than the fields on the con­duct­ing walls. This struc­ture, op­er­at­ing near the cut­off fre­quency of the HEM12 mode, spans a fre­quency range where the wave­length and phase ve­loc­ity vary sig­nif­i­cantly. This prop­erty can be ex­ploited to gen­er­ate un­du­la­tor ac­tion with short pe­ri­ods for the gen­er­a­tion of high bright­ness x-rays. The fre­quency range of in­ter­est would be from 18 to 34.5-GHz. The goal would be to gen­er­ate x-rays on the fun­da­men­tal mode over a range of 45 to 90-kev. The tun­abil­ity would be achieved by chang­ing the source fre­quency while main­tain­ing a con­stant on-axis equiv­a­lent un­du­la­tor field strength of 0.5-T.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB098  
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WEPIK121 Computation of Synchrotron Radiation on Arbitrary Geometries in 3D with Modern GPU, Multi-Core, and Grid Computing GPU, undulator, simulation, radiation 3238
 
  • D.A. Hidas
    BNL, Upton, Long Island, New York, USA
  
  Funding: Supported by the U.S. Department of Energy under contract DE-SC0012704
Open Source Code for Ad­vanced Ra­di­a­tion Sim­u­la­tion (OS­CARS*) is an open source pro­ject being de­vel­oped at Brookhaven Na­tional Lab­o­ra­tory for the com­pu­ta­tion of syn­chro­tron ra­di­a­tion from ar­bi­trary par­ti­cle beams in ar­bi­trary mag­netic (and elec­tric) fields on ar­bi­trary geome­tries in 3D. OS­CARS was de­signed with con­sid­er­a­tions for mod­ern large scale com­put­ing in­fra­struc­ture. These in­clude the abil­ity to use GPUs for com­pu­ta­tions, multi-threaded com­pu­ta­tions, and util­i­ties for grid (or cloud) com­put­ing. Pri­mary ap­pli­ca­tions in­clude, but are not lim­ited to, the com­pu­ta­tion of spec­tra, pho­ton flux den­si­ties, and no­tably, power den­sity dis­tri­b­u­tions on ar­bi­trary geome­tries in 3D which is of in­ter­est in ac­cel­er­a­tor com­po­nent study and de­sign. This mod­ern ap­proach and sev­eral com­plex geome­tries will be high­lighted and elab­o­rated on.
* http://oscars.bnl.gov 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK121  
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