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caf4c908-00b4-4c59-8e31-29afcd199cb9 | downtotherequiredsub-fsrangeinplasmaaccelerators[ 1],
buttheycanbecostlyandmayrepresentasignificantfoot-
printforfutureacceleratorslikeEuPRAXIAorotherplasma-
basedfacilities,wheresizeisanimportantfactor. Transverse
deflectingstructures,however,areaninterceptingdiagnostic,
which can make this method impractical for moni... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 0 |
317b6337-1879-4364-bc94-78eaf8c11d58 | work uses point-to-point spatial imaging of the CTR source
todeterminelongitudinalfeaturesofthebunchprofile[ 6–8].
∗A.M.Guisao-Betancur@liverpool.ac.uk
†joseph.wolfenden@cockcroft.ac.ukCTR SPATIAL IMAGING
When assuming full transverse coherence of the bunch,
that is, its rms transverse size 𝜎𝑟<< 𝛾𝜆/2𝜋 [5], the coh... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 0 |
e36d2e78-9059-4e5b-98c6-482f44b2189f | ButwithCTRinparticular,thefocusofthiswork,thereis
anotheroptiontostudytheparticledistributionbyanalyzing
theimagedistributionfortheparticlebunch 𝑑𝐼𝑖
bunch/𝑑𝑟[6,7].
This image corresponds to a point-to-point spatial image of
theCTRsource,anditisdescribed,foragivenbandwidth
Δ𝜔, by:
𝑑𝐼𝑖
bunch
𝑑𝑟≈ 𝑁2𝑒∫Δ𝜔𝑑2𝐼... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 0 |
065e0437-e489-4558-8635-57fcc95a4e26 | ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6087
MC6.T03: Beam Diagnostics and Instrumentation 2747WEP: Poster session WEP6087
Content from this work may be used under the terms of the CC BY 4.0 licence (© 2026). Any distribution of this work must maintain attribution to the author(s), title... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 0 |
4835bf72-68cb-4a5f-8028-497791957201 | transitionradiation(TR)target. Thesecondmirror,OAP2,
isplacedintheanti-symmetricconfiguration, thusobtain-
ing the spatial image at its RFL = 203.2mm . The ratio of
the RFLs determines the magnification, in this case, a 2x
magnification.
Foramoreextensivedescriptionofthemonitor’sworking
principle and design process, se... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 1 |
061a27a1-cb0b-4c49-a196-0c00c1137c5a | window (high-resistivity float zone silicon HRFZ-Si) and
the reflectance of the mirrors (protected silver), while 𝐷(𝜔)
willbethepyroelectricarrayresponse. Fortheresultsshown
inthiscontribution,aslightmirrormisalignmenthasbeen
introduced in the simulations, with a 0.4∘rotation, to study
the monitor’s performance under... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 1 |
6c096759-9fb4-4ae8-bca0-62715e7a7b62 | peak irradiance at the detector as a function of frequency is
shown in Fig. 2, highlighting that high-frequency compo-
nents(shorterbunchesandshorterbunch-profilefeatures)
willdominatethefinalCTRimagesoverlow-frequencycom-
ponents.
Figure 2: Peak detector irradiance vs. frequency from simu-
lations.
Thisdataneedstobege... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 1 |
d6cdadcf-c293-4d81-a0da-2403127ff4df | ones),foreachprofile,theapparentbunchlengthisreported
on the top row by two measures. 𝜏FWHMis the full width
athalfmaximumofthedistribution,but √𝑚2iscalculated
from the second moment as a measure of how spread out
the signal “mass”is along the time axis.
Figure 3: ImagesgeneratedforpurelyGaussian profiles.
The second... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 1 |
54ac6142-6340-4ea6-af1e-277c247edb34 | growing tail/background.
Forthelastsetofsimulations,thegoalistostudysmall
bumps/features in bunch profiles that correspond to high-
frequency features, even though they have small ampli-
tudes,andhowtheycanaffecttheoutputCTRimage. The
main peak is set to 30%of the total amplitude at fixed
𝜏FWHM-peak=20fsand the second... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 1 |
5b8f90d1-3d07-4f07-8221-256a94c5d10f | Figure 5: Images generated for a profile composed of two
Gaussians (one fixed and one growing) for obtaining two
peaks.
The results of the image analysis for the three cases are
shown in Fig. 6. For the CTR image analysis, the FWHM
inboth imagedirections is used asa simple measure of the
changes. High-frequency image c... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 2 |
b884a8fe-f8d0-4b89-bd99-5b554d45d28b | √𝑚2inTDS:reference[fs]),thefeatureswithinthebunch
are different, and the resulting CTR images capture these
differencesindifferentways. ForGaussianprofilesinFig. 6
(a),initiallythereisasteadyandproportionalgrowthinboth
directions of the CTR image, eventually starting to decrease
in the horizontal direction for longer ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 2 |
ae39cad4-3a7c-49c2-ba97-f119dd6a4257 | the peak become dominant. It should be noted that this
monitoring method does not provide any phase information
abouttheparticledistribution,meaningthatinthecaseof
Fig.6(b-c), a mirrored profile would produce exactly the
same CTR image.
It is evidentthat the relationships are nonlinear and diffi-
cult to capture with a... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 2 |
e7987d06-7293-450a-8e51-391a1b5846c7 | CONCLUSION
SpatialCTRimageswerestudiedfromasimulation-based
perspective. The simulations are a valuable source of infor-
mationfordevelopingthismonitor,astheyenabletestingits
capabilitiesacrossawiderangeofparticledistributionsthat
may not be available experimentally. The image analysis
showsthattheCTRspatialimagesareco... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 2 |
8034e2cb-626f-4d40-b40a-944fb15269d6 | funds, and grant agreement no. 101188004; the Cock-
croft Institute core grant no. STFC ST/V001612/1; and
the AWAKE-UK phase II project funded by STFC under
grant no. ST/X005208/1.17th International Particle Accelerator Conference, Deauville, France JACoW Publishing
ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 2 |
0864423f-b6a3-4a77-bbdb-9844d2b656ff | REFERENCES
[1]M.C.Downer etal.,“Diagnosticsforplasma-basedelectron
accelerators”, Rev.Mod.Phys. ,vol.90,no.3,p.035002,2018.
doi:1/zero.alt4.11/zero.alt43/RevModPhys.9/zero.alt4./zero.alt435/zero.alt4/zero.alt42
[2]D. V. Karlovets and A. P. Potylitsyn, “Universal description
fordifferenttypesofpolarizationradiation”, ar... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 3 |
6bd82298-3280-42a3-b185-b7e8ff7a0a02 | tion at free-electron lasers”, Phys. Rev. Accel. Beams , vol. 23,
no. 6, p. 062801, 2020.
doi:1/zero.alt4.11/zero.alt43/PhysRevAccelBeams.23./zero.alt4628/zero.alt41
[5]T. J. Maxwell et al., “Coherent-radiation spectroscopy of few-
femtosecondelectron bunchesusinga middle-infraredprismspectrometer”, Phys. Rev. Lett. , ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 3 |
1aaef20a-ce68-4e83-88a0-21d353dfc9b1 | Accel.Beams , vol. 11, no. 1, p. 012801, 2008.
doi:1/zero.alt4.11/zero.alt43/PhysRevSTAB.11./zero.alt4128/zero.alt41
[8]A. Guisao-Betancur et al., “Designing a femtosecond-
resolutionbunchlengthmonitorusingcoherenttransitionra-
diation images”, Instruments , vol. 9, no. 4, pp. 1-15, 2025.
doi:1/zero.alt4.339/zero.alt4/... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 3 |
339731e5-4385-4e78-a8d8-2796762341bd | ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6087
2750 MC6.T03: Beam Diagnostics and InstrumentationWEP6087 WEP: Poster session
Content from this work may be used under the terms of the CC BY 4.0 licence (© 2026). Any distribution of this work must maintain attribution to the author(s), title... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6087.pdf | 3 |
5f5fa388-ea19-4be0-97d0-8c689afdc7c4 | STUDIES OF UNUSUAL PICKUP GEOMETRIES FOR THE ARC BEAM
POSITION MONITORS OF THE FCC-ee
E. Howling∗, P. N. Burrows, John Adams Institute for Accelerator Science, Oxford, UK
M. Gasior, European Organization for Nuclear Research, Geneva, Switzerland
Abstract
Theelectron-positronFutureCircularCollider(FCC-ee)
has challengin... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 0 |
70494d97-165f-4d2d-8f63-4c0dbe0f806e | the design of the FCC-ee arc BPM pickups.
REQUIREMENTS FOR FCC-EE BPMS
The FCC (Future Circular Collider) is a proposed col-
lider project to be built at CERN, with the FCC-ee being
the electron-positron machine stage of the project. It would
be the largest ever operating accelerator, with high inten-
sityelectronbeams... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 0 |
6a432556-54ff-4f57-b301-00f736b7d5bd | impedanceofthebuttonsmustbeverylowandthematerials
used must have suitable thermal properties.
Button BPMs typically have a circular button, but due
tothechallengingcombinationofhighresolutionandlow
impedance requirements forthe FCC-ee arc BPMs, a more
unusual geometry may be required.
ELLIPTICAL BUTTONS
Simulationstudi... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 0 |
13d9e3fa-d9bc-49fd-8bbb-457edf1aebcb | fortheFCC-eearcBPMs,simulationsofsimplifiedelliptical
buttons of different ratios were run in CST using FCC-ee
beamparametersforthe 𝑡̄𝑡(SR)and𝑍(BS)operatingmodes
∗emily.howling@physics.ox.ac.ukTable 1: FCC-ee Beam Mode ParametersUsed [ 1]
Mode Bunch charge Bunch length
[nC] [mm]
𝑍(BS) 34.3 15.5
𝑡̄𝑡(SR) 24.8 1.8
a... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 0 |
73fc6e36-fd81-4cc8-9cb7-04aec56404d3 | button of ratio 4 in the FCC-ee beam pipe.
Theareaoftheellipsewaskeptconstant. The‘ratio’refers
to the length along the 𝑧axis of the button divided by the
width along the 𝑥or𝑦axis. A CST model of an elliptical
pickup with ratio 4 in the FCC-ee beam pipe is shown in
Fig.1. Thebackgroundismodelledasaperfectelectriccon... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 0 |
60d2480f-e5fc-4f10-bf0d-59ed4bbb3ed3 | resultsareshown,asthesetendtobemoreaccurateforCST
models with waveguide ports. The results for the simulated
wake-loss factor for different ellipse ratios using the 𝑡̄𝑡(SR)
parametersareshowninFig. 2,withahyperboliccurvefit
to them.17th International Particle Accelerator Conference, Deauville, France JACoW Publishing... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 0 |
a2c7ead2-3566-4045-8d85-326685fbd816 | Figure 2: wake-lossfactorvsratio forelliptical buttons.
Figure3: Voltagevstimeforthesimulatedresponseofel-
liptical BPM buttons, unfiltered (top) and after a simulated
75MHzfilterwasapplied(bottom),usingthe 𝑍(BS)param-
eters.
Thevoltageresultsfrom thesesimulations(Fig. 3)show
thatthemoreeccentrictheellipse,thelowerthe... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 1 |
dcf6b4da-9a13-4e18-acba-a04052b91083 | (SR) parameters.Therealpartofthewakeimpedancespectrumfor4dif-
ferent ratios (Fig. 4), shows that the smaller ratio buttons
show resonant peaks of much higher amplitudes and greater
widths.
Thewakepotentialcreatedbybuttonsofdifferentratios
is shown in Fig. 5. The higher the ratio, the lower the initial
amplitude of the ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 1 |
f626b6da-1a7c-44cd-a6b2-c4a9b1ba09ee | parameters.
A higher ratio ellipse button is beneficial both in terms
of reducing the wake-loss factor and increasing the filtered
peak-to-peakvoltage. Sincetheaddedbenefitsdecreaseas
ratioincreases,andringinginthewakepotentialisgreater
forhigherratios,aratioof4couldbeagoodcompromise
betweensignificantlyreducingthewake... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 1 |
5a849b3e-d828-4e6e-9d44-579c1a47e61d | models. Thewakepotentialfortherectangularbuttonresults
showed some beating and slightly higher amplitude ringing
after a few metres than the other models.
The wake-loss factors for the different models are sum-
marised in Table 2. All the ratio-4 shapes have a lower
wake-loss factor than the circular button, with the e... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 1 |
0254f5a4-e985-4eaa-907d-66879742965e | Table 2: Wake-lossFactorforDifferent Button Shapes
Button shape Wake-loss factor
[V/pC]
Circle 3.27×10−2
Ellipse 0.788×10−2
Pill 1.34×10−2
Rectangle 1.93×10−2
ASYMMETRIC PICKUPS
In this case an ‘asymmetric’ pickup refers to a pickup
withanon-constantgap,i.e. thebuttonisoff-centreofthe
holeitfitsinto. Thisasymmetrycould... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 2 |
70a8b758-0804-4239-acba-e322e6d05e40 | frequency for different button offsets.
Figure 7: Magnitude of the wake impedance spectrum vs
frequency for different gap sizes of an offset button.
Theresultsshowedthatthegreatertheoffsetinanydirec-
tion, the lower the amplitude of the largest resonant peak in
the wake impedance spectrum, as shown in Fig. 6. Offsets
o... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 2 |
fc2c6925-b36c-4bd2-9e47-a4b79e4347d6 | offsettingthebuttonreducestheresonancepeakamplitudeto
less than the largest resonance peak of an equivalent button
withasmallergap,whilstkeepingitatahigherfrequency,
matchingthe largestresonant peak frequencyofthe model
withthelargergap. Boththese propertiesarebeneficial,as
higher frequency resonances typically interac... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 2 |
f8bbb323-310c-4946-890f-de253faea7bc | that the power loss to the pickup is equivalent to that of a
smallerpickup,butwithagreatermassofmaterialtoabsorb
it.
Amodelwitha 3mmretractionofan 8mmradiusbutton
screenedbehinda 4mmradiusholewascomparedtoa 4mm
radius pickup at the beam pipe radius. There was an over
50 % reduction in peak-to-peak voltage when the butt... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 2 |
7a3323ba-f8d8-442d-951b-37e745517467 | overall not as advantageous as an ellipse.
Itisbeneficialtohaveslightlyasymmetricalbuttons,as
this reduces the amplitude of the largest resonance in the
wake impedance spectrum, whilst keeping the resonant fre-
quency of the largest peak the same. Other ways of mak-
ing the button more asymmetrical, such as offsetting ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 2 |
85b4d935-4e67-4cd1-825c-58c7bce98274 | ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6090
MC6.T03: Beam Diagnostics and Instrumentation 2753WEP: Poster session WEP6090
Content from this work may be used under the terms of the CC BY 4.0 licence (© 2026). Any distribution of this work must maintain attribution to the author(s), title... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 2 |
172723f6-9e40-4811-95e1-a5f709a941b8 | REFERENCES
[1]B. Auchmann et al., “Future Circular Collider Midterm Re-
port”, CERN, Geneva, Switzerland, 2024.
doi:1/zero.alt4.17181/mhas5-1f263[2]A. Novokhatski et al., “The design and electromagnetic analy-
sesofthenewelementsintheFCC-eeIRvacuumchamber”,
inProc. IPAC’24 , Nashville, TN, USA, May 2024, pp. 2508–
2511... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6090.pdf | 3 |
6a35f47a-f185-40a2-9a5c-ce95a2cca0e3 | COMMISSIONING THE PASSIVE STRUCTURE WAKEFIELD
DECHIRPER ON CLARA∗
T.J. Overton†,1,3, B. Higuera Gonzalez2,3, J.K. Jones1,3, T.H. Pacey1,3, Y. Saveliev1,3
1ASTeC STFC Daresbury Laboratory, Daresbury, UK
2The University of Manchester, Manchester, UK
3The Cockcroft Institute, Daresbury Laboratory, Daresbury, UK
Abstract
A... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 0 |
48760ba9-e984-478a-9b08-3ef86fe9527e | andchangesinlongitudinalphasespaceduetothedechirper.
We outline plans for further measurements and discuss how
the dechirper will support upcoming user programs.
INTRODUCTION
CLARA is an advanced medium-energy electron test
beamfacility,capableofdeliveringelectronbuncheswithup
to250MeV/cmomentumand250pCchargefortherequ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 0 |
37f16f06-a872-40ff-bdba-9c2d914b8dcf | bunchitselfincorrugated-metallicordielectric-linedwaveg-
uides to decelerate the tail of the bunch such that the energy
is more monotonic across the bunch and increase the 6D
brightness [ 3–5]. A passive wakefield dechirper has been
designed and installed on CLARA and a simulation cam-
paign conducted before use to eva... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 0 |
02647d03-18ff-467a-8626-1762470d72cd | ∗Worksupported byThe CockcroftInstituteand the STFC.
†toby.overton@stfc.ac.ukthird, and fourth/final linacs, corresponding to approximate
beam momenta of 35, 200, and 250 MeV/crespectively. In
thesectionafterthethirdlinac,avariablebunchcompres-
soris positionedto allowforvaryingbunchlengthsforthe
needsofindividualexper... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 0 |
61b509d0-0f19-4c88-b2aa-0b483a1995e7 | transporttotheFEBEarctotheexperimentalarea. Delivery
to user experiments in the FEBE chamber is via an arc with
non-zero𝑅56,thereforeremovalofthebeamchirpcanallow
longitudinal diagnostics before the arc to be directly related
to beam parameters for user experiments.
Thepassivedielectricdechirperisdesignedforcontrol-
l... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 0 |
37757cf1-9561-4cd0-86f8-753fede0a527 | plate length (with a 10 mm gap between the two DLWs).
Each plate can be controlled with two actuators along the
plate, allowing for gap and tilt control. Together with the
controls for the parallel plate it is possible to control the
dechirpergap,transversecentre, andtilt. This reducescon-
straintsonbeamtrajectoryintot... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 0 |
e9b1e573-7ac1-4614-acf8-e1510f67d83d | two DLWs effectively cancel each other and conserve the
beam emittance [ 6].17th International Particle Accelerator Conference, Deauville, France JACoW Publishing
ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6091
MC6.T03: Beam Diagnostics and Instrumentation 2755WEP: Poster session WEP6091
Co... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 0 |
5be67f4e-4435-4db9-bf70-86cf43443ee7 | Figure 1: Schematicof the CLARA beamline. The position of the passivewakefielddechirper is highlighted in pink.
Figure2: Schematicofthepassivewakefielddechirper. Driv-
ingstagesarelabelledforthefirst,horizontallyorientated,
DLW (DCP1). The same controls exist for the second, verti-
cally orientated, DLW (DCP2).
INITIAL... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 1 |
2f0b7698-a7ee-4f3c-aeda-dbfc74e22b72 | byitschirpwithapositivechirpwhenunder-compressedand
negative chirp (higher energy head) when over-compressed.
Opticsweresetbeforethedechirpertoensurebeamtrans-
portthroughthedechirperacrossthefullrangeofgaps;with
a minimum gap size of 1 mm this required a beam envelope
with sizes ∼ 100µm across the 0.4 m total dechirpe... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 1 |
0a2c65d7-5297-484f-8491-9232ee37321d | method outlined in Ref. [ 8]. The energy spectra, with the
dechirper in and out was measured in a dispersive section
after a dipole, 2 m downstreamfrom the dechirper exit. The
longitudinal wakefield excited by the measured profile is
calculatedusingthemethodinRef.[ 9],andthechangein
energy spectra used to reconstruct t... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 1 |
68270a74-14aa-42d5-8e48-b932839f807d | reducingby90%(1.46to0.15MeV).Thefullenergyspread,
definedasthefullwidthat10%maxreducedby25%(2.65to
1.99MeV).TheFWHM significantlyreduces,howeverthe
fullenergyspreaddoesnotreducebythesamemagnitude;
this can be explained by the large energy spread at the head
seen in Fig. 3which cannot be reduced by the dechirper.
Thedec... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 1 |
a51f87bf-c27a-4e0f-a7ab-98ed66540503 | Figure 4: Measured 50% and 10% full width energy spread
as a function of dechirper gap, with equal DCP1 and DCP2
gaps. Measuredspectraarethesumof10shotswitherror
barsrepresentingthestandarddeviationofindividualshot
measurements. Lines are smooth fits to the measurements.
Figure5: Percentageincreaseinpeakenergyspectrain... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 2 |
6b7d518f-0caa-455f-97c3-19d1620eeace | peakintensity,theoptimaldechirpingiswitha1.25mmgap.
Themeasuredandsimulatedspectraatthisgapareshown
in Fig.6with good agreement between measurement and
simulations.
Transverse Beam Quality Preservation
The effectiveness of the orthogonal DLW design was
tested by comparing the emittance measured at the end
of the CLARA ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 2 |
220f5494-011d-46bf-83ff-d7212fa7fd17 | sultsofeachquadrupolescanareshowninFig. 7;withthefit
used to calculate the emittance plotted for each dataset. The
normalisedemittance, (𝜖𝑛,𝑥,𝜖𝑛,𝑦),withthedechirperinwas
measured as (3.08,2.60)±(0.26,0.14) mm mrad and with
Figure 6: Measured energy spectra with the dechirper out
(black) and 1.25 mm DCP1 and DCP2 ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 2 |
4809cdbd-fb00-48f9-b996-d4b314b19e01 | planeswithequalminimummeasuredbeamsizeswiththe
dechirper in and out.
CONCLUSIONS
Theresults presentedinthese proceedingsdemonstrate
the successful commissioning of the passive dielectric
dechirper at CLARA. Initial results show that the dechirper
operatesasexpectedwithagreementseenbetweensimula-
tions and measurements ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 2 |
1114952c-504b-40fe-9210-5be7467c07d1 | ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6091
MC6.T03: Beam Diagnostics and Instrumentation 2757WEP: Poster session WEP6091
Content from this work may be used under the terms of the CC BY 4.0 licence (© 2026). Any distribution of this work must maintain attribution to the author(s), title... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 2 |
8940de6f-f91d-4f3a-a9a5-13a5e674eb29 | REFERENCES
[1]E. W. Snedden et al., “Specification and design for full energy
beamexploitationofthecompactlinearacceleratorforresearch
and applications”, Phys. Rev. Accel. Beams , vol. 27, no. 4,
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[2]J. Joneset al., ”Compressio... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6091.pdf | 3 |
0a0f57f1-1eac-4cfd-b4d1-cd1a10012c76 | Canada, May 2019, pp. 3401-3404.
doi:1/zero.alt4.18429/JACoW-IPAC2/zero.alt418-THPAK/zero.alt474
[5]Y. W. Gong et al., “Beam performance of the SHINE
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c4b971b1-34d7-4019-885f-43c3a7507b27 | structureforbunchlengthandphasespacediagnostics”,SLAC
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[9]S.S.Baturin etal.,“Transverseoperatormethodforwakefields
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9e04ca36-e201-4e16-b8cb-faeb1c92298a | TRANSVERSE PHASE SPACE TOMOGRAPHY AT CLARA
USING GENERATIVE MACHINE LEARNING
M.A. Johnson∗1,2, A.D. Brynes1,2, J.K. Jones1,2, M. King1,2, A. Wolski2,3
1ASTeC, STFC Daresbury Laboratory, Sci-Tech Daresbury, Warrington WA4 4AD, UK
2The Cockcroft Institute, Sci-Tech Daresbury, Warrington, WA4 4AD, UK
3Department of Physic... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 0 |
3bb53955-4c1f-4e76-99ab-3c477a758734 | formance, and for validating the simulation models used
during its design. Phase space tomography is a powerful
technique for reconstructing a beam’s charge distribution in
phasespace;recentmachinelearningadvanceshaveledto
faster, higher-resolution tomographic methods such as gen-
erative phase space reconstruction. In... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 0 |
590f6e21-2b6a-4b24-b862-f958cc674556 | brightness, ultra-short electron bunches to a variety of de-
mandinguserexperiments[1,2]. CLARAiscurrentlyunder-
goingbeamcommissioningatitsmaximumbunchcharge
(250pC)andrepetitionrate( 100Hz),afteranextendedshut-
downtoallow theinstallationofamajorupgrade. Thispe-
riod saw the addition of a new, high-repetition-rate (u... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 0 |
a9d593a6-062b-4433-ac65-a60a0f39dac3 | structure, and also allows measurement of the betatron cou-
pling. Conventionally, tomography in multiple degrees of
freedom has required large data sets and significant compu-
tationalresources,makingitunsuitableforonlinebeammea-
∗mark.johnson@stfc.ac.uksurements. However,severalauthorshaverecentlydemon-
stratednewtom... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 0 |
f0b490fe-7547-4db9-8dd0-ff53f69d44d1 | this application, since it can reconstruct an accurate charge
distributionthatincludesthebeam’sdetailedsubstructure.
Previous tomography studies at CLARA [8,12,13] have
reconstructedthelow-energy( 35MeV)beamproducedby
theaccelerator’sfrontend,whichwaspreviouslyoperatedas
aseparateuserfacilitybetween2018–2022[14]. Howev... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 0 |
9d536b0c-4260-4f86-adfb-0b8e1dd464b5 | hasalreadybeenusedinsupportofseveraluserexperiments.
METHOD
Experimental Data
Figure1showsthesectionofCLARAthatwasusedfor
tomography measurements in this study. The transport and
diagnosticssectionimmediatelyafterthefinallinacincludes
ten independently-powered quadrupole magnets, and four
YAG screens for observing the ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 0 |
d049d751-0335-4c9d-a4f3-6ef2df94ce32 | experiments take place [16].
Here, we demonstrate the tomography methods used at
CLARA by reconstructing the charge distribution of the
250MeV electronbeamforbunchchargesupto 250pC. For
the purposes of this study, we made measurements of an17th International Particle Accelerator Conference, Deauville, France JACoW Publ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 0 |
1600b673-f249-477c-b456-c269101ca9a5 | Figure 1: Simplified schematic showing the section of CLARA that was used for tomography measurements. The distances
between elements are approximately to scale. Components that are not relevant to this study are not shown for clarity.
uncompressedbeam,withthelinacphasessettominimize
thebeamenergyspread. Weaimedtorecon... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 1 |
2bd871db-41c9-46fe-8776-d1d5fd4ea61e | reconstructionandobservationpoints. Figure2showsthe
horizontal and vertical phase advance for each step of the
quadrupolescanthatwasusedtocollecttomographydata.
Quadrupole settings were chosen to keep the Twiss beta
functionsattheobservationpointapproximatelyconstant,
avoiding beams with very small or large aspect rati... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 1 |
61327278-e904-498c-b91f-f021f4d65dcb | Data Analysis
For this study, we used the generative phase space recon-
struction ( GPSR) technique to reconstruct the transverse
phase space of the CLARA beam from a series of experi-
mental beam images. The GPSR approach has already beendescribed in detail elsewhere [9 –11,15]; however, a brief
summary is included he... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 1 |
fe8947ff-8346-4f01-ba79-4ea6141d2b68 | Togenerateaparticledistributionthatisconsistentwith
experimentallymeasuredbeamimages,thegenerativemodel
must be trained. This is done by repeatedly using the model
to generatenew macroparticle distributions, whileoptimiz-
ing its parameters to minimize the difference between the
measured beam images and an equivalent s... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 1 |
ebf2e754-aacc-446e-aeaf-478f65f5d8ac | methodin python,usingthe PyTorchMLlibrary[20]. The
generativemodelwasimplementedasasimpleneuralnet-
work, with a single hidden layer comprised of 15 neurons
connectedbyTanhactivationfunctions. Wecalculatedthe
simulated beam images using Cheetah[21,22], a fast, dif-
ferentiable linear optics code that is specifically de... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 1 |
be3ab435-284e-4b64-86a9-c4bd78bd55f9 | RESULTS
Thetomographymethoddescribedintheprevioussection
wasappliedtomeasurementsofthe 250MeV CLARAbeam,17th International Particle Accelerator Conference, Deauville, France JACoW Publishing
ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6092
2760 MC6.T03: Beam Diagnostics and InstrumentationWE... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 1 |
d2abd169-d76c-4f39-acd5-fb7b3a894e2d | Figure3: ProjectionsoftheCLARAbeam’stransverse( 𝑥,𝑝𝑥,𝑦,𝑝𝑦)phasespaceatthereconstructionpoint,fora 250MeV
electron beam with a bunch charge of 30pC.
Table 1: Reconstructed RMS Emittances for the 250MeV
CLARA Electron Beam for Bunch Charges up to 250pC
Parameter 30 pC 100 pC 250 pC
𝜖𝑛,𝑥[µm] 1.2 1.8 2.3
𝜖𝑛,𝑦[µ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 2 |
d08f6b8e-955c-4929-b41f-0fa3792e0b4d | reflect its expected performance when fully operational.
Thereconstructedphasespacescanbevalidatedbyusing
them to predict the beam profile at the observation point for
differentquadrupolesettings. Figure4showscomparisons
between three measured and reconstructed beam profiles,
each corresponding to a different bunch cha... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 2 |
a5700fb4-d405-44e5-880e-f462883074b4 | missioning. It has already been deployed to support several
user experiments, providing an accurate representation of
the beam’s phase space distribution that is often needed for
analysis of the experimental data.Notably, the section of CLARA shown in Fig. 1 includes
both a transverse deflecting cavity (TDC) and a spec... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 2 |
90b1cda4-22af-4a27-b169-e8e338dad664 | bunchchargesandquadrupolesettings. Thesolid(dashed)
contourdenotes 50%(10%)ofthemaximumbeamintensity.17th International Particle Accelerator Conference, Deauville, France JACoW Publishing
ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6092
MC6.T03: Beam Diagnostics and Instrumentation 2761WEP: ... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 2 |
201e5783-45b3-4c97-a6e8-43872b8105d0 | REFERENCES
[1]J.A. Clarke, D. Angal-Kalinin, N. Bliss, R. Buckleyet al.,
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[2]D. Angal-Kalinin, M.A. Johnson, J.K. Jones, T.H. Paceyet
al., "CLARA Commissioning and First Friendly User Exper-
iments",presentedatIPAC’26,Deauville,F... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 3 |
f62b9873-90ab-4ca9-ac84-a0c29808d27b | Tomography of Relativistic Electron Beams",Nucl. Instrum.
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[6]V. Yakimenko, M. Babzien, I. Ben-Zvi, R. Malone and
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ing a High-Precision Tomography Technique",Phys. Rev. ST
Accel. Beams6, 122801, 2003... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 3 |
060b3526-3bd6-4268-9a89-18f0dda519a3 | [9]R. Roussel, A. Edelen, C. Mayeset al., "Phase Space Re-
construction from Accelerator Beam Measurements Using
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[10]R. Roussel, J.P. Gonzalez-Aguilera, E. Wisniewskiet al.,
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0b553ae8-aebb-4971-84b8-33cfae3114e9 | H.Kockelbergh,"TransversePhaseSpaceCharacterization
in an Accelerator Test Facility",Phys. Rev. Accel. Beams23,
032804, 2020.
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[13]A.Wolski,D.Botelho,D.DunningandA.E.Pollard,"Accel-
eratorBeamPhaseSpaceTomographyUsingMachineLearn-
ing to Account for Variations in Beamline Componen... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 3 |
4a5b4880-e43e-4279-b346-bab0ecb48bf8 | Simulations",Phys. Rev. Accel. Beams27, 074601, 2024.
doi:10.1103/PhysRevAccelBeams.27.074601
[16]E.W. Snedden, D. Angal-Kalinin, A.R. Bainbridgeet al.,
"Specification and Design for Full Energy Beam Exploita-
tion of the Compact Linear Accelerator for Research and
Applications",Phys. Rev. Accel. Beams27, 041602, 2024.... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 3 |
d5c2d4f9-6ce9-4170-baaf-26627b46ce89 | Optimization",Phys. Rev. Accel. Beams28, 114603, 2025.
doi:10.1103/cbds-lst1
[20]A. Paszke, S. Gross, F. Massaet al., "PyTorch: An Imper-
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Advances in Neural Information Processing Systems32,2019,
pp. 8024–8035.doi:10.48550/arXiv.1912.01703
[21]O.Stein,I.V.Agapov,... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 3 |
056c590c-0ad1-4950-89d4-f2870d7ed3ba | ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6092
2762 MC6.T03: Beam Diagnostics and InstrumentationWEP6092 WEP: Poster session
Content from this work may be used under the terms of the CC BY 4.0 licence (© 2026). Any distribution of this work must maintain attribution to the author(s), title... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6092.pdf | 3 |
4dd77d36-be42-4b3c-967b-c28f90e11cf9 | SPACE CHARGE COMPENSATION TIME MEASUREMENT
FOR A PULSED, HIGH-CURRENT H– ION BEAM
E. L. Flannigan∗, R. Abel, D. R. Emerson, D. Faircloth,
B. John, K. Jonathan, D. Morris, O. Tarvainen
Science and Technology Facilities Council, Swindon, United Kingdom
Abstract
Strongspacechargeeffectsinpulsed,high-intensityhy-
drogenion... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 0 |
37040d7a-d4c7-4f4f-8aed-c1bcb9fef9ba | a Multi-Pixel Photon Counter has been developed at ISIS
Neutron and Muon Source to measure the beam-induced
light emission during SCC. The transmission through the
acceptance-limitedRFQ,measuredbybeamcurrenttrans-
formers at the entrance and exit, can also be used to deter-
mine SCC time. These two diagnostics have bee... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 0 |
1c604918-5b61-44fa-8bef-3f898773ecb8 | in beam losses. The space charge of the beam is reduced
throughthespacechargecompensation(SCC)process. This
process occurs due to ionisation of the background gas in
the LEBT, e.g. H−+ H2→H−+ H+
2+ e−for H−beams.
The secondary particles created are either repelled by the
beam potential (electrons for H−beams) or trappe... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 0 |
65fac754-417e-4fdc-8bf5-eaa057a60442 | ∗erin.flannigan@stfc.ac.ukwhere𝑛𝑔is the gas number density, 𝜎(𝐸𝑏)is the energy-
dependent beam-induced ionisation cross section, and 𝑣𝑏
is the speed of the beam [ 1]. This equation assumes that
only the primary beam ionises the background gas and that
allcompensatingparticlescreated aretrappedbythebeam
potential... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 0 |
66364372-5ed8-4aaa-be8b-0544e505c049 | ormasswillleadtobeamlossesthroughelectrondetachment.
Changes to the focusing fields used in magnetostaticLEBTs
may also affect the SCC time, as the magnetic field will
affect the dynamics of the secondary particles relevant to
the process [ 2,3].
As the SCC process is crucial to beam transport in the
LEBT,manydiagnosti... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 0 |
261b7fc6-54b7-4373-8bd3-043e8d112bdb | normal accelerator operation, emphasise the advantage of
non-invasive diagnostic techniques for studying SCC. This
work uses two non-invasive diagnostic techniques, beam
current transformers (BCTs) and an optical diagnostic, to
estimate the SCC time or equilibration time and to deter-
minethe optimal conditions forcomp... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 0 |
d81fb080-8fcd-4796-8e34-8666d668799c | magnetLEBT.Adiagnosticchambersitsbetweenthesecond
and third solenoid magnet. The LEBT transports ∼35mA17th International Particle Accelerator Conference, Deauville, France JACoW Publishing
ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6093
MC6.T03: Beam Diagnostics and Instrumentation 2763WEP:... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 0 |
a54cd2ad-5b7d-492a-b055-1235a1cc4f17 | Figure1: AschematicoftheISISNeutronandMuonSource
H−ion source, 36keVLEBT and 665keVRFQ accelerator.
ofH−beam,whichismatchedintothesubsequentradiofre-
quency quadrupole (RFQ) accelerator for acceleration up to
665keV. Figure1shows a schematic of the ISIS ion source,
LEBT and RFQ, with the location of relevant diagnostic... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 1 |
cd90c93d-0079-4b61-bd45-299962e55c9c | fortransportofthesteady-stateofthebeampulse,lowtrans-
mission through the RFQ will result from the divergence
andemittancegrowthoftheionbeampriortoreachingcom-
pensation. This period will therefore provide an estimate of
the SCC time described in Eq. ( 2).
Optical Diagnostic
AstheH−beamistransportedthroughtheLEBT,itexc... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 1 |
a5b78b54-2ffc-4391-850a-da8409a8ca60 | A non-invasive diagnostic based on a multi-pixel photon
counter (MPPC) has been developed at ISIS to measure the
beam-induced and electron-induced light emission from an
H−beam [7]. The optical diagnostic system includes the
MPPC, a silicon photomultiplier to count photons at visible
wavelengths and low light levels, w... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 1 |
497db552-f9ed-4f78-a3fc-bdfaf0dbf72c | chamber is shown in Fig. 1.
RESULTS AND DISCUSSION
Tobetterillustratetheperiodoflowtransmissionthrough
the RFQ, the signals from BCT2 and BCT3 are normalised
tomatchthesteadystateofthebeamcurrentpulseandthe
differencebetweenthetwoistaken. Thissignaldifferenceis
usedinthisworkasanestimationoftheSCCtime,allowing
comparis... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 1 |
45899b29-6c30-41ae-8dc6-2241e6d0581b | is measured using the BCT at the entrance of the RFQ. The
resultingpeakmaybeusedtoestimatetheequilibrationtime
of the LEBT system.
To examine the effect of beam current changes to SCC
time, the arc discharge current of the Penning source was
scanned to change the beam current by 20%. No effect was
seen on either the BC... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 1 |
10b7b994-9017-4b85-8af1-19191b5f8b9b | suredbythe vacuumgaugein thediagnosticchamberindi-
catedinFig. 1. Whilethepressureatthediagnosticchamber
is quoted, the pressure in the LEBT will be a gradient from
theionsourcepressures( 4.3×10−5mbarto6.6×10−5mbar
in this scan) to the lower pressures achieved at the entrance
oftheRFQ.TheSCCtimemeasuredduringthescanran... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 1 |
d8b2e208-4988-46d9-927a-2d1e6bdfae43 | nostic. The rangeof the solenoid settings scans the on-axis
magnetic field inside of the second solenoid from 0.03Tto
0.3T. However,thescanresultsinnegligibledifferencein
the magnetic field at the location of the optical diagnostic.
In general, decreasing the solenoid current decreased the
timetoreachequilibriumforboth... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 1 |
b2665858-5928-44ab-9d63-10cc0df07583 | Figure2: The(a)differenceinBCTsignalattheentrance
and exit of the ISIS RFQ and (b) normalised optical signal/
beam current for a range of LEBT background pressures.
two methods are apparent at the higher solenoid currents.
Thisis likelylargelydue to poor transport and matchingof
thebeamthroughtheRFQ,resultinginadecreas... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 2 |
8a84b4b8-e38c-46f7-b8de-77819c451672 | between the solenoids.
Whiletheoveralltrendofallparametricscansarecompa-
rable,differencesobservedbetweentheequilibrationtime
measuredbytheBCTsandtheopticaldiagnosticsaredueto
multipledifferencesbetweenthediagnostictechniques. The
BCTsmeasurethetimeperiodpriortothebeamreachingthe
sizeacceptedbytheRFQ;ifcompensationproc... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 2 |
18c03d61-79e1-4e09-b70c-6320fab58403 | beamcurrentforarangeofcurrentsettingsonthesecond
solenoid magnet of the ISIS LEBT.
the beam potential, and therefore electron energy, change.
Finally,theBCTswillmeasurethecumulativechangetothe
SCCtimeintheLEBTwhiletheopticaldiagnosticcanonly
measure changes to the compensation process occurring
within the MPPC field-of... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 2 |
ebb21a58-288c-4390-83f3-047b787a1616 | theLEBT.Thesetechniqueswillbeusedforfurtherparamet-
ricsweepsandmonitoringintheISISLEBTandtheoptical
diagnostic will be tested on other LEBT systems, including
those for H+beams.
REFERENCES
[1]N.Chauvin etal., “Transport of intense ion beams and space
charge compensation issues in low energy beam lines”, Rev.
Sci. Inst... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 2 |
04e52a5f-63ab-458a-93ad-ce464600a460 | [2]B. Johnetal., “Effect of magnetic field on space chargecom-
pensation in negative hydrogen ion beams: a computational
study”,J. Instrum. , vol. 20, no. 5, p. C05024, 2025.
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[3]K. Jonathan et al., “A particle-in-cell stud... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 3 |
a91455f5-bffe-41f2-ab5c-4a2615515a1b | [6]R. Sidlow et al., “Operational experience of Penning H- ion
sources at ISIS”, in Proc. EPAC’96 , Sitges, Spain, Jun. 1996,
paper THP084L, pp. 1525–1527.
[7]D.Morris etal.,“Micorwavedrivenspace-chargecompensa-
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Venice, Italy, May 2023, pp. 2767-2769.
doi:... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 3 |
ebdd6a20-3e49-4aeb-9ad4-1ce622a035c3 | ISBN: 978-3-95450-252-3 ISSN: 2673-5350 doi: 10.18429/JACoW-IPAC2026-WEP6093
2766 MC6.T03: Beam Diagnostics and InstrumentationWEP6093 WEP: Poster session
Content from this work may be used under the terms of the CC BY 4.0 licence (© 2026). Any distribution of this work must maintain attribution to the author(s), title... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6093.pdf | 3 |
36d907a9-961d-4469-9196-fbc29b7dfffe | PYTHON BASED CONTROL AND DIAGNOSTIC SYSTEMS FOR AREAL
LINEAR ACCELERATOR
G. Amatuni, M. Yazichyan*, A. Grigoryan1, B. Grigoryan, A. Hovakimyan1, H. Sargsyan1, L. Alek-
sanyan, E. Mnatsakanyan1, H. Davtyan, A. Otarov, A. Vardanyan grigoryan @asls.candle.am, Center
for the Advancement of Natural Discoveries using Lig... | D:\Daily_ihep\Conferences\IPAC2026\WEP\WEP6095.pdf | 0 |
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