RF phase effect in the ion-guide laser ion source (IG-LIS)

Jens Lassen; Maryam Mostamand; Ruohong Li

REVIEW 4 major objections 5 minor 9 references

RF phase effect in the ion-guide laser ion source (IG-LIS)

T0 review · 4 major / 5 minor · reviewed 2026-08-07 · deepseek-v4-flash

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Pith's one-line read This paper claims that synchronizing the laser trigger with the RF waveform in an ion-guide laser ion source, so ions are born at a chosen RF phase, raises extracted beam intensity by 10–50%, and that gating the RF envelope can purify the…

desk verdict RF-phase locking in IG-LIS is a real effect worth exploiting, but the 10-50% gain is not nailed down by the current data. read the letter →

arxiv 2502.08863 v1 pith:CE4O7JAJ submitted 2025-02-13 physics.acc-ph physics.ins-det

Ruohong Li , Maryam Mostamand , Jens Lassen This is my paper · ORCID

classification physics.acc-phphysics.ins-det

keywords laserionsourceion-guideRFQphaseeffectfringefieldresonantionizationbeampurificationsynchronizationRFenvelopegating

verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

An ion-guide laser ion source creates ions with a laser pulse inside a radio-frequency quadrupole, and this paper claims that the point in the RF cycle at which that pulse fires determines how many of the ions survive the trip out. When the laser trigger and the RF waveform generator are locked to a common master clock, all ions in a pulse are born at essentially the same RF phase, and the transmitted beam intensity becomes a periodic function of that phase. Choosing the optimal phase improves ion extraction by 10–50 percent in suppression mode, where surface-ionized contamination is rejected. The paper further shows that turning the RF envelope on and off gates the beam itself, suppressing surface-ionized species outside the laser pulse and offering a fast-kicker alternative for purification. If correct, the result means a simple synchronization upgrade gives existing ion-guide laser ion sources both higher intensity and an intrinsic high-frequency beam modulator.

What carries the argument

The load-bearing object is the initial RF phase $\varphi$, the phase of the quadrupole drive waveform at the instant a laser pulse creates the ions. A master clock locks the laser trigger to the RF generator so that $\varphi$ is reproducible from pulse to pulse. The paper's working model is a multiplicative transmission factor, $P_{\mathrm{syn}} = P_{\mathrm{unsyn}}(a + b \sin(\omega t + \varphi))$, where $P_{\mathrm{unsyn}}$ is the time profile without phase locking, $a$ is the phase-insensitive fraction, and $b$ is the fraction whose transmission is modulated by the fringe field; a second term, $c\,P_{\mathrm{phase}}(\varphi')$, adds the numerically simulated regular RFQ-acceptance effect that appears once the RF envelope is gated. The fringe field in the roughly 2 mm gap between the repeller and the RFQ entrance is identified as the source of the dominant $1f$ modulation, because ions cross that gap in only about 1.5 RF cycles under the offline conditions.

What would settle it

Take the same phase-locked source and deliberately stretch the ion pulse, for example by cooling the crucible, lengthening the transfer tube, or using a laser power that broadens the ionization window in time, until ions arrive at the RFQ entrance over several RF periods; if the synchronized best phase then loses its 10–50% advantage over the unsynchronized average, the common-birth-phase mechanism is confirmed, and if the gain survives, the improvement must come from a different effect. A direct check is also to scan the phase in fine steps around the optimum for a light element and confirm that the modulation depth grows roughly as expected from the shorter pulse length.

Watch

Extended reading notes

Core claim

The central claim is that the transmitted intensity of a laser-ionized beam from an ion-guide laser ion source depends on the RF phase at ion birth, not just on how many atoms the lasers ionize. Because laser resonance ionization in the cold volume finishes within about a hundred nanoseconds while the 0.4 MHz RF period is about 2.5 microseconds, every ion created by one laser pulse experiences nearly the same initial phase at the RFQ entrance. That initial phase controls transmission through two mechanisms: the regular RFQ acceptance, which varies as $2f$ with the phase, and the fringe field in the short gap between the repeller and the RFQ, which adds a $1f$ variation. In experiments with laser-ionized praseodymium (Pr), silver (Ag), and uranium (U), scanning the phase produced a periodic modulation of the transmitted rate, and the best phase improved extraction by 10–50% in suppression mode; for silver the gain was 20–50%. The paper models the time profile as the unsynchronized profile multiplied by a sinusoidally modulated phase factor, and shows that gating the RF amplitude suppresses surface-ionized contamination by a factor of 2–3.

Load-bearing premise

The central premise is that the ions created by a laser pulse are all born within a time window much shorter than one RF period, so the whole bunch shares a single initial RF phase; if ionization, thermal release, or transport stretched the bunch over several RF cycles, the phase effect would average out and the 10–50% gain would not appear as described.

Editorial extensions

If this is right

Existing ion-guide laser ion sources can gain 10–50% more beam intensity in suppression mode by adding a master clock and choosing the right phase, with no change to the ion-guide hardware.
Phase locking turns the ion source into a beam-intensity modulator at hundreds of kHz, which the paper plans to use for phase-sensitive detection in collinear laser spectroscopy.
RF envelope gating suppresses surface-ionized isobars outside the laser pulse by a factor of 2–3, providing an alternative to a fast kicker for beam purification.
The optimal phase shifts with RF frequency and electrode potentials, so the method requires a per-element, per-condition phase calibration rather than a single global setting.
The effect is mass-dependent: lighter elements are expected to show stronger phase dependence, so extending the method to Mg or Be should produce larger gains than the 10–50% seen for Pr, Ag, and U.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

If the $1f$ fringe-field modulation is indeed controlled by how many RF cycles an ion spends in the entrance gap, then the modulation depth in different regions of the ion time profile could serve as a diagnostic of where ions were born, not just of how many survive.
The same phase-locking principle should transfer to other pulsed ionization sources that feed an RFQ ion guide, including devices at other isotope-separator facilities, so the intensity gain may be a general property of RFQ ion guides rather than unique to this source.
The unexplained uranium anomaly near -120 degrees hints at a phase-sensitive transmission channel not captured by the two-term model; a fine phase scan with more statistics could reveal whether some ions are being bunched or recaptured in the fringe field.
Because the optimal phase varies with frequency, a closed-loop controller that dithers the phase and maximizes downstream current could automate the optimization, turning the 10–50% gain into a continuously maintained setting.

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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Desk Editor's Note

read the letter

Good to see this paper—it demonstrates a practically important effect: synchronizing the laser trigger to the RF waveform in an IG-LIS lets you choose the RF phase at ion birth, which measurably changes transmitted ion intensity. The Pr and Ag offline data, plus the online U data, are the first systematic phase-locking measurements for IG-LIS, and the RF-envelope gating idea is a useful alternative to a fast kicker. The authors also deserve credit for disclosing the U anomaly and the limits of their model.

The soft spots are real but not disqualifying. Equations (1)-(2) are descriptive fits to the same time profiles they reproduce, with parameters adjusted per figure. That's acceptable for illustrating the effect, but the paper would be stronger if it made even one predictive statement, like using a parameter set from Pr to predict Ag or U. The Fig. 5 phase scans have no point-to-point error bars and no repeated fixed-phase measurements, so the 20-50% improvement for Ag is not well bounded. The U anomaly at -120 and -150 degrees is worrying because the 20% online improvement may be entangled with that unexplained rate increase; the authors should explicitly say whether the optimum they found is inside the anomalous region. The stress-test note is fair on these points.

I would push back on the suggestion that the central claim is not firmly established. The existence of the phase effect is solid—the Ag phase scan shows a clear periodic pattern with two valleys, and the Pr time profile shows a deep modulation that tracks the RF frequency. What's not firm is the exact magnitude and the clean attribution for U.

This is a paper for ISOL practitioners and laser ion source developers. With modest revisions—error bars on the phase scans, a repeat at one fixed phase, and a clear statement about where the U optimum sits relative to the anomaly—it would be a solid applied physics contribution. Send it to peer review.

Referee Report

4 major / 5 minor

Summary. This paper reports an experimental investigation of the effect of synchronizing the laser trigger with the RF waveform in TRIUMF's ion-guide laser ion source (IG-LIS). Time profiles and total rates were measured for laser-ionized Pr (offline), Ag (offline), and U (online) as the RF phase was varied. The authors observe periodic modulation of the transmitted ion rate with the RF period and report total-rate improvements of 10-50% in suppression mode. They model the modulation with a sinusoidal factor (Eq. 1) and an extended version including a regular-phase-effect term (Eq. 2), and demonstrate that RF envelope gating can suppress surface-ionized species in transmission mode.

Significance. If the reported phase effect is robust, the result is practically significant: synchronizing the laser to the RF phase is a near-zero-cost improvement for IG-LIS facilities, and the demonstrated RF gating offers an alternative to fast kickers. The paper's strength is that the phase-dependent modulation is directly visible in the time profiles for three elements and in two modes, with the observed period matching the RF period. The authors also explicitly acknowledge the limitation of the unexplained anomaly in the online U data. However, the quantitative 10-50% improvement is not firmly established because the supporting total-rate measurements are not replicated and the online U data contain an unexplained anomaly. The model in Eqs. (1)-(2) is a fitted parameterization rather than a predictive simulation, so it does not independently confirm the physical mechanism.

major comments (4)

[Section 5, Fig. 6] The online U data contain an abrupt rate increase at -120 and -150 degrees, accompanied by an extra ion group in the 75-80 us region, and the authors state 'We currently have no explanation for this anomalous behavior.' Because the 20% U improvement and the abstract's 10-50% range include this dataset, the total-rate gain cannot be confidently attributed to the RF-phase mechanism; the anomaly may indicate an unidentified systematic effect. The authors should either investigate this anomaly or exclude and clearly caveat the U rate improvement in the abstract and summary.
[Section 4, Fig. 5] The phase scans in Fig. 5 are presented without point-to-point error bars, and no repeated measurements at a fixed phase are shown. The scan-up and scan-down curves differ at several phases, and the global check that the phase-averaged rate matches the unsynchronized rate does not rule out a monotonic drift (e.g., laser power or target temperature) over the scan. Since the 20-50% improvement claim is based on total-rate differences between optimized and averaged phases, replicate measurements with error bars are needed to establish the magnitude.
[Section 3, Eqs. (1)-(2)] The model is fitted to the same data it is used to reproduce: parameters a, b, c, phi, and phi' are adjusted per panel in Figs. 2 and 4, and P_un-syn is taken from the smoothed unsynchronized profile. The agreement of the blue curves with the red data is therefore not an independent test of the model. The sinusoidal fringe-field term in Eq. (1) is an ad-hoc assumption. To support the claim that the fringe field is the dominant mechanism, the authors could test the model's predictions at other RF frequencies or amplitudes, or compare with a particle simulation.
[Section 3, Fig. 4] The manuscript states that synchronization increases the rate by 'about 10%' in suppression mode (Fig. 4a vs 4b), but the accompanying sentence says 'Before this optimization, the ion rate was 7% lower,' which is ambiguous: it is unclear whether the baseline is the unsynchronized rate or a different phase setting. The text should state the exact comparison and provide the statistical and systematic uncertainties on these two rates.

minor comments (5)

[Section 2] Typo: 'FWFH' should be 'FWHM' when describing the Ti:Sa laser pulse length.
[Abstract and Section 6] The abstract's '10-50%' range aggregates results from different elements and modes; consider reporting the per-element ranges with a note that the online U data include an unexplained anomaly.
[Section 3] In Eq. (2), P_phase is not explicitly defined in the text as the simulation result from Fig. 3; state this definition directly after the equation.
[Section 3] The sentence 'similar to the substructure observed in the GdB6 hot cavity LIS 16' cites reference [16], which is a general quadrupole book chapter by Dawson; this does not appear to be the intended source for a GdB6 LIS substructure study.
[Section 5 and Fig. 6] The inset plot showing total rate versus phase is described in the text but may be difficult to read; consider enlarging it or presenting it as a separate panel.

Circularity Check

1 steps flagged · score 4.0 of 10

Fitted Eqs. (1)-(2) reproduce the same time profiles they are built from, while the central measured 10-50% improvement is independent.

fitted input called prediction [Section 3, Eqs. (1)-(2) and Fig. 2 caption]
"In the simulations, the smoothed data (blue in Fig. 2a) from the raw data (red in Fig. 2 a) was used for 𝑃un-syn. ... the theoretical mode l result (blue) matches the experimental data (red) well with the parameters a = 1, b = 0.6, and 𝜑 = 2.3 rad. ... The simulation parameters using eq. (2) are: b): a = 0.25, b = 0.9, c = 1.3, 𝜑 = 2.6 rad and 𝜑′ = 2.5 rad; c) and d): a = 0.0, b = 0.15, c = 1.5, 𝜑 = 2.6 rad and 𝜑′ = 2.5 rad."

Eq. (1) constructs the 'synchronized' profile P_syn by multiplying the measured unsynchronized profile P_un-syn by a sinusoid whose coefficients (a, b, phi) are chosen to fit the synchronized data in the same figure; Eq. (2) does the same with an added c*Pphase term and per-panel parameters. The agreement between the simulated (blue) and experimental (red) curves is therefore imposed by construction rather than derived from an independent fringe-field/RFQ model. Calling this a 'theoretical model result' and 'simulation' overstates what is an empirical fit. The central experimental claim of a 10-50% improvement from phase optimization is a direct measured rate comparison and does not reduce to this fitted model.

full rationale

The central claim is an experimental measurement: when the laser trigger and RF generator are phase-locked and the phase is tuned, the total transmitted rate increases by 10-50% in suppression mode relative to the unsynchronized case. This is supported by direct count-rate comparisons in Figs. 2, 4, 5, and 6 and does not depend on the model equations. The only circular element is in the modeling sections: Eqs. (1)-(2) use the smoothed unsynchronized time profile as input and free coefficients a, b, c, phi, phi' that are re-fit for each panel, so the simulated curves are not independent predictions of the observed modulation; their visual match is a consequence of the fit. That is a presentation/overinterpretation issue, not a circular derivation of the main result. The paper also openly notes an unexplained online U anomaly, which affects robustness of the 20% U improvement but is not a circularity. No load-bearing self-citation chain or definitional equivalence is present, so the overall circularity is moderate rather than severe.

Assumptions & free parameters 7 free parameters · 4 assumptions · 0 invented entities

The experimental core is a direct measurement, so no free parameters are needed for the central observation. The free parameters all belong to the interpretive model in Eqs. (1)-(2), which is explicitly a smoothed-data fit. The main assumptions are standard modeling choices, with the sinusoidal RF approximation and the source-region time-profile interpretation being the most significant.

free parameters (7)

Eq. (1) amplitude a = 1 (Fig. 2b)
Fitted to the synchronized Pr time-profile; represents the phase-insensitive ion fraction.
Eq. (1) fringe-field modulation amplitude b = 0.6 (Fig. 2b)
Fitted to reproduce the depth of the 1f modulation.
Eq. (1) initial phase phi = 2.3 rad (Fig. 2b)
Fitted to align the sinusoidal modulation with the measured time profile.
Eq. (2) coefficients for Fig. 2c = a=0.3, b=0.05, c=1.0, phi=2.3 rad, phi'=3.1 rad
Fitted to the gated-RF Pr time profile.
Eq. (2) coefficients for Fig. 2d = a=0.25, b=0.15, c=1.0, phi=2.3 rad, phi'=2.6 rad
Fitted to the gated-RF Pr time profile with a different gate width.
Eq. (2) coefficients for Fig. 4b = a=0.25, b=0.9, c=1.3, phi=2.6 rad, phi'=2.5 rad
Fitted to the suppression-mode Pr time profile.
Eq. (2) coefficients for Fig. 4c and 4d = a=0.0, b=0.15, c=1.5, phi=2.6 rad, phi'=2.5 rad
Fitted to the gated suppression-mode Pr time profiles.

assumptions (4)

domain assumption The RF waveform can be approximated as Vrf sin(omega t + phi) in simulations.
The experimental RF is a 50% duty square wave, but Fig. 3 and Eqs. (1)-(2) use a sinusoidal form. The authors call this 'without loss of generality', but it is an approximation that affects the phase-effect shape.
domain assumption Ion birth time spread in the cold ionization volume is much shorter than one RF period.
Section 1 assumes laser ionization occurs within about 100 ns while the RF period is 2.5 us at 0.4 MHz, giving each ion pulse a well-defined initial RF phase.
domain assumption Time-profile bumps correspond to ions from different source regions as in hot-cavity LIS literature.
Section 3 uses the double-bump structure attribution from Ref. 11 to assign ions to the RFQ entrance versus the crucible. This interpretation is borrowed from a different geometry and may not transfer exactly.
ad hoc to paper The fringe-field transmission modulation is sinusoidal.
Eq. (1) postulates a simple sinusoidal phase dependence. This is a phenomenological assumption fitted to the data, not derived from the fringe-field equations.

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Cite this review

Pith. "Pith review of RF phase effect in the ion-guide laser ion source (IG-LIS)." pith.science (2026). https://pith.science/paper/CE4O7JAJ

@misc{pith2026250208863,
  author       = {Pith},
  title        = {Pith review of: RF phase effect in the ion-guide laser ion source (IG-LIS)},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/CE4O7JAJ}},
  note         = {Machine review of arXiv:2502.08863}
}

read the original abstract

The effect of the phase between the radio frequency (RF) waveform driving the ion guide and the laser pulses generating ions on the intensity of the transmitted ion beam has been studied. Experiments were conducted at TRIUMF's offline laser ion source test stand (LIS-stand) and online at the isotope separator and accelerator (ISAC) facility for radioactive ion beam delivery. In this study, a master clock is used to synchronize the laser trigger for laser ionization and the RF waveform generator driving the ion guide, so that laser ionization within the ionization volume inside the RF ion guide will occur at a specific RF phase which affects the ions' transmission through the RFQ. At optimal phase the ion extraction from the IG-LIS can be improved by 10-50%. Simulations were run considering both fringe field and RFQ phase effects. The method also provides an additional function of IG-LIS to modulate the laser-ionized ions at hundreds of kHz, allowing phase-sensitive detection for experiments downstream. In addition, modulation of the RF envelope (on and off like a gating device) in transmission mode allows for the suppression of surface-ionized species outside the laser-ion pulse, which provides an alternative to a classic fast kicker for beam purification.

Figures

Figures reproduced from arXiv: 2502.08863 by the authors.

**Figure 1.** Cross-sectional view of the IG-LIS used at the LIS-stand. The ion guide’s free-field radius r0 is 5 mm and the RFQ rod radius is 3 mm. The length of the IG-LIS rod is 34 mm. The offline crucible has 3 mm inner diameter and 15 mm length. To examine the phase effect on the ion transmission inside IG-LIS, the RF waveform generator (Keysight/Agilent 33511B) and laser-trigger delay gate generator (BNC 575) were synchroni… view at source ↗

**Figure 4.** Being synchronized or not, the total transmission rate is essentially unchanged in transmission mode (Fig. 2a and 2b), but increases by about 10% in suppression mode when properly synchronized (Fig. 4a and 4b). Fig. 4b shows the results after phase optimization, achieved by adjusting the initial phase of the waveform on the RF generator. Before this optimization, the ion rate was 7% lower. 4. Offline experimental te… view at source ↗

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Reference graph

Works this paper leans on

9 extracted references · 9 canonical work pages

[1]

containment ions

Introduction Resonant ionization laser ion sources (RILIS), combining high ionization efficiency and elemental selectivity, are widely used at isotope separator online (ISOL) facilities 1,2. However, traditional hot-cavity RILIS suffers from isobar contamination from surface-ionized species. To decoup le the laser ionization region from the hot target and...

work page
[2]

Offline experimental test using laser-ionized Pr The experimental test was conducted at TRIUMF’s offline laser ion source test stand (LIS-stand) 12. The Pr sample (50 μl, Alfa Aesar Specpure atomic spectroscopy standard solution, 1 μg/μl Pr in the form of Pr(NO3)x in 2% HNO3) was pipetted onto a thin foil and dried at 110 °C in an oven. The sample-loaded ...

work page
[3]

a” represents the ions unaffected by the fringe-field phase effect. The second term with coefficient “ b

Phase effect in IG-LIS transmission and suppression mode First, the laser frequencies and alignment were optimized for Pr laser ionization with unsynchronized clocks for the laser trigger and RFQ waveform generat or. The IG-LIS was set at transmission mode with the crucible potential at 5 V and all other electrodes – namely the repeller, RFQ bias, and exi...

work page
[4]

the different parts of the time profile are generated in distinct regions of the IG-LIS, and therefore have different ion birth environments and velocity distributions, which cannot be fully described by Eq. (2)

work page
[5]

In reality however, a fair portion of ions are generated inside the RFQ, which has slightly higher transmission than what Fig

𝑃phase represents the transmission rate if the ions start ed at the RFQ entrance and passed through the entire length of the RFQ. In reality however, a fair portion of ions are generated inside the RFQ, which has slightly higher transmission than what Fig. 3 plots

work page
[6]

This subtly is not captured in the model expressed in eq

at the end of the RFQ, the extraction field penetrates into the RFQ . This subtly is not captured in the model expressed in eq. (2). Additionally, eq. (2) only considers the three groups of ions: one unaffected by the phase condition, one primarily affected by the fringe field, and another primarily affected by the regular phase effect. However, some ions...

work page
[7]

In the offline test stand, an IG -LIS phase test on Ag was conducted

Offline experimental test using Ag To further study the phase effect , more experimental tests of IG -LIS were done on different elements. In the offline test stand, an IG -LIS phase test on Ag was conducted. The ionization scheme for Ag was 328.163 nm + 827.576 nm + 532 nm (non-resonant ionization). The laser powers were 20 mW for 328.163 nm, 15 mW for 8...

work page
[8]

238U was extracted from a UCx target irradiated by 9.8 A of 480 MeV protons

Experimental test online using U The IG-LIS phase effect has also been studied online at ISAC using 238U. 238U was extracted from a UCx target irradiated by 9.8 A of 480 MeV protons. The target heating current was 340 A and the transfer line was resistively heated with a current of 270 A (standard ISAC target ion source operating parameters). U was laser...

work page

Show all 9 references

[9]

Ion beam production and study of radioactive isotopes with the laser ion source at ISOLDE,

Summary In this work, the phase effect of IG-LIS has been studied offline at LIS-stand and online at the ISAC facility. In the experiments with laser-ionized Pr, Ag, and U, the ion rates from the IG-LIS were improved by 10-50% in suppression mode by synchronizing the laser tri...

2017

Pith tools

Reviewed August 7, 2026 · model on record in the stance chip above.

[1] [1]

containment ions

Introduction Resonant ionization laser ion sources (RILIS), combining high ionization efficiency and elemental selectivity, are widely used at isotope separator online (ISOL) facilities 1,2. However, traditional hot-cavity RILIS suffers from isobar contamination from surface-ionized species. To decoup le the laser ionization region from the hot target and...

work page

[2] [2]

Offline experimental test using laser-ionized Pr The experimental test was conducted at TRIUMF’s offline laser ion source test stand (LIS-stand) 12. The Pr sample (50 μl, Alfa Aesar Specpure atomic spectroscopy standard solution, 1 μg/μl Pr in the form of Pr(NO3)x in 2% HNO3) was pipetted onto a thin foil and dried at 110 °C in an oven. The sample-loaded ...

work page

[3] [3]

a” represents the ions unaffected by the fringe-field phase effect. The second term with coefficient “ b

Phase effect in IG-LIS transmission and suppression mode First, the laser frequencies and alignment were optimized for Pr laser ionization with unsynchronized clocks for the laser trigger and RFQ waveform generat or. The IG-LIS was set at transmission mode with the crucible potential at 5 V and all other electrodes – namely the repeller, RFQ bias, and exi...

work page

[4] [4]

the different parts of the time profile are generated in distinct regions of the IG-LIS, and therefore have different ion birth environments and velocity distributions, which cannot be fully described by Eq. (2)

work page

[5] [5]

In reality however, a fair portion of ions are generated inside the RFQ, which has slightly higher transmission than what Fig

𝑃phase represents the transmission rate if the ions start ed at the RFQ entrance and passed through the entire length of the RFQ. In reality however, a fair portion of ions are generated inside the RFQ, which has slightly higher transmission than what Fig. 3 plots

work page

[6] [6]

This subtly is not captured in the model expressed in eq

at the end of the RFQ, the extraction field penetrates into the RFQ . This subtly is not captured in the model expressed in eq. (2). Additionally, eq. (2) only considers the three groups of ions: one unaffected by the phase condition, one primarily affected by the fringe field, and another primarily affected by the regular phase effect. However, some ions...

work page

[7] [7]

In the offline test stand, an IG -LIS phase test on Ag was conducted

Offline experimental test using Ag To further study the phase effect , more experimental tests of IG -LIS were done on different elements. In the offline test stand, an IG -LIS phase test on Ag was conducted. The ionization scheme for Ag was 328.163 nm + 827.576 nm + 532 nm (non-resonant ionization). The laser powers were 20 mW for 328.163 nm, 15 mW for 8...

work page

[8] [8]

238U was extracted from a UCx target irradiated by 9.8 A of 480 MeV protons

Experimental test online using U The IG-LIS phase effect has also been studied online at ISAC using 238U. 238U was extracted from a UCx target irradiated by 9.8 A of 480 MeV protons. The target heating current was 340 A and the transfer line was resistively heated with a current of 270 A (standard ISAC target ion source operating parameters). U was laser...

work page