arxiv: 2604.15905 · v1 · submitted 2026-04-17 · ⚛️ physics.ins-det

Recognition: unknown

Electroluminescence Yield Measurements in Xenon Gas with the NEXT-DEMO++ Detector

NEXT Collaboration: J. Renner , J.D. Villamil , N. L\'opez-March , K. Mistry , P. Novella , A. Sim\'on , V. \'Alvarez , J.M. Benlloch-Rodr\'iguez

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M. Cid C. Cortes-Parra R. Esteve F. Kellerer J. Mart\'in-Albo A. Mart\'inez G. Mart\'inez-Lema M. Mart\'inez-Vara M. Querol P. Saharia M. Sorel S. Teruel-Pardo H. Almaz\'an L. Arazi I.J. Arnquist F. Auria-Luna S. Ayet Y. Ayyad C.D.R. Azevedo F. Ballester J.E. Barcelon M. del Barrio-Torregrosa F.I.G.M. Borges A. Brodoline N. Byrnes A. Castillo E. Church X. Cid C.A.N. Conde F.P. Coss\'io R. Coupe E. Dey P. Dietz C. Echeverria M. Elorza R. Felkai L.M.P. Fernandes P. Ferrario P. Ferrero Manche\~no F.W. Foss Z. Freixa J. Garc\'ia-Barrena J.J. G\'omez-Cadenas J.W.R. Grocott R. Guenette J. Hauptman C.A.O. Henriques J.A. Hernando Morata P. Herrero-G\'omez V. Herrero C. Herv\'es Carrete Y. Ifergan A.F.B. Isabel B.J.P. Jones L. Larizgoitia A. Larumbe P. Lebrun F. Lopez R. Madigan R.D.P. Mano A. Marauri A.P. Marques R.L. Miller J. Molina-Canteras F. Monrabal C.M.B. Monteiro F.J. Mora K.E. Navarro D.R. Nygren E. Oblak I. Osborne J. Palacio B. Palmeiro A. Para I. Parmaksiz A. Pazos J. Pelegrin M. P\'erez Maneiro I. Rivilla C. Rogero L. Rogers B. Romeo C. Romo-Luque E. Ruiz-Ch\'oliz F.P. Santos J.M.F. dos Santos M. Seemann I. Shomroni A.L.M. Silva P.A.O.C. Silva S.R. Soleti J. Soto-Oton J.M.R. Teixeira J.F. Toledo C. Tonnel\'e S. Torelli J. Torrent A. Trettin P.R.G. Valle M. Vanga P. V\'azquez Cabaleiro J.F.C.A. Veloso L.M. Villar Padruno J. Waiton A. Yubero-Navarro

Authors on Pith no claims yet

Pith reviewed 2026-05-10 07:23 UTC · model grok-4.3

classification ⚛️ physics.ins-det

keywords electroluminescence yieldhigh-pressure xenontime projection chamberNEXT-DEMO++83mKr calibrationpressure dependencereduced electric fieldgas detectors

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The pith

Xenon gas electroluminescence yield slope changes by about 5% with pressure above 5 bar.

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

This paper measures the electroluminescence yield in xenon gas using a high-pressure time projection chamber prototype across pressures from 2.0 to 9.4 bar. The reduced yield Y/p is fitted linearly against reduced field E/p, revealing a modest change in slope that begins around 5 bar and grows with increasing pressure. A sympathetic reader cares because electroluminescence provides the primary signal in xenon detectors used for rare-event searches, so any pressure dependence affects calibration and energy resolution. The work directly addresses prior inconsistencies in the literature about whether the yield slope is independent of pressure.

Core claim

The reduced electroluminescence yield Y/p was measured as a function of reduced electric field E/p at pressures from 2.0 to 9.4 bar in the NEXT-DEMO++ detector using the 41.5 keV de-excitation peak of 83mKr. Linear fits to these data show a modest approximately 5 percent change in slope, with the change beginning around 5 bar and increasing as pressure rises to 9.4 bar.

What carries the argument

The linear fit to the reduced electroluminescence yield Y/p versus reduced field E/p, with the pressure variation of its slope as the measured quantity.

If this is right

Electroluminescence models for xenon must incorporate a small pressure-dependent term above 5 bar.
Energy reconstruction in high-pressure xenon time projection chambers will need updated parameters to maintain accuracy.
The size of the slope shift increases steadily with pressure up to at least 9.4 bar.
Some earlier disagreements in published electroluminescence data may be explained by this pressure effect.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

At the 10-15 bar pressures planned for next-generation xenon detectors the effect could become larger and require dedicated calibration.
The change may originate in pressure effects on electron transport or excitation rates, suggesting targeted microscopic simulations.
Repeating the study with controlled variations in gas purity would test whether the dependence is intrinsic to xenon itself.

Load-bearing premise

The observed change in slope arises from a real physical dependence of the electroluminescence process on pressure rather than from unaccounted detector effects or analysis choices.

What would settle it

An independent measurement at 7 bar using a different light sensor geometry or analysis method that finds the slope exactly matches the value measured below 5 bar.

Figures

Figures reproduced from arXiv: 2604.15905 by A. Brodoline, A. Castillo, A.F.B. Isabel, A. Larumbe, A.L.M. Silva, A. Marauri, A. Mart\'inez, A. Para, A. Pazos, A.P. Marques, A. Sim\'on, A. Trettin, A. Yubero-Navarro, B.J.P. Jones, B. Palmeiro, B. Romeo, C.A.N. Conde, C.A.O. Henriques, C. Cortes-Parra, C.D.R. Azevedo, C. Echeverria, C. Herv\'es Carrete, C.M.B. Monteiro, C. Rogero, C. Romo-Luque, C. Tonnel\'e, D.R. Nygren, E. Church, E. Dey, E. Oblak, E. Ruiz-Ch\'oliz, F. Auria-Luna, F. Ballester, F.I.G.M. Borges, F.J. Mora, F. Kellerer, F. Lopez, F. Monrabal, F.P. Coss\'io, F.P. Santos, F.W. Foss, G. Mart\'inez-Lema, H. Almaz\'an, I.J. Arnquist, I. Osborne, I. Parmaksiz, I. Rivilla, I. Shomroni, J.A. Hernando Morata, J.D. Villamil, J.E. Barcelon, J.F.C.A. Veloso, J.F. Toledo, J. Garc\'ia-Barrena, J. Hauptman, J.J. G\'omez-Cadenas, J. Mart\'in-Albo, J.M. Benlloch-Rodr\'iguez, J.M.F. dos Santos, J. Molina-Canteras, J.M.R. Teixeira, J. Palacio, J. Pelegrin, J. Soto-Oton, J. Torrent, J. Waiton, J.W.R. Grocott, K.E. Navarro, K. Mistry, L. Arazi, L. Larizgoitia, L.M.P. Fernandes, L.M. Villar Padruno, L. Rogers, M. Cid, M. del Barrio-Torregrosa, M. Elorza, M. Mart\'inez-Vara, M. P\'erez Maneiro, M. Querol, M. Seemann, M. Sorel, M. Vanga, N. Byrnes, NEXT Collaboration: J. Renner, N. L\'opez-March, P.A.O.C. Silva, P. Dietz, P. Ferrario, P. Ferrero Manche\~no, P. Herrero-G\'omez, P. Lebrun, P. Novella, P.R.G. Valle, P. Saharia, P. V\'azquez Cabaleiro, R. Coupe, R.D.P. Mano, R. Esteve, R. Felkai, R. Guenette, R.L. Miller, R. Madigan, S. Ayet, S.R. Soleti, S. Teruel-Pardo, S. Torelli, V. \'Alvarez, V. Herrero, X. Cid, Y. Ayyad, Y. Ifergan, Z. Freixa.

**Figure 2.** Figure 2: An example summed PMT waveform for a candidate [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗

**Figure 3.** Figure 3: (top) shows the X-Y distribution of reconstructed events for a representative run (at 5 bar), along with the applied fiducial cut. Following the above selection, the S2 energy spectrum was constructed from the summed PMT charge in the S2 peak (in photoelectrons). The spectrum was fit with a Gaussian function to extract the mean S2 yield for the 41.5 keV Kr peak [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗

**Figure 4.** Figure 4: Reduced electroluminescence yield Y/(p · d) as a function of reduced electric field E/p for three different pressures. For each pressure, the reduced yield values are fit to a line to extract the corresponding values of A and X0 (Eqn. 2). Note that only E/p values greater than 1.1 kV/cm/bar were included in the fit, though residuals are shown for all data points, highlighting the discrepancy observed at th… view at source ↗

**Figure 5.** Figure 5: Fit parameters A (above) and X0 (below) for each yield vs. E/p curve (see [PITH_FULL_IMAGE:figures/full_fig_p006_5.png] view at source ↗

read the original abstract

The NEXT-DEMO++ detector, a high-pressure xenon gas time projection chamber serving as a prototype for the NEXT-100 experiment, was used to measure the electroluminescence (EL) yield as a function of reduced electric field ($E/p$) across pressures from 2.0 to 9.4 bar, utilizing the 41.5 keV de-excitation peak of $^{83m}$Kr. These measurements were made to examine the pressure dependence of the slope of the reduced EL yield $Y/p$, which has shown inconsistencies in the literature. The reduced yield was fitted with a linear model, revealing a modest ($\sim$5%) change in slope, beginning around 5 bar and increasing with pressure up to 9.4 bar.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

New measurements of reduced EL yield in xenon show a modest ~5% slope change with pressure up to 9.4 bar.

read the letter

The main point from this paper is new measurements of the electroluminescence yield in high-pressure xenon gas using the NEXT-DEMO++ detector. They tracked the reduced yield Y/p as a function of E/p from 2.0 to 9.4 bar with the 41.5 keV peak from 83mKr and found a roughly 5% change in the slope of the linear fit that starts around 5 bar and grows with pressure. The experiment is well set up for this task. The paper covers the detector details, how they calibrated with the krypton source, and the linear fitting at each pressure point. This directly targets the pressure dependence that earlier studies had left inconsistent, so the data adds a useful data point for the community working on xenon TPCs. One potential soft spot is that the observed shift is small, and confirming it is truly from the physics of the EL process rather than some detector-specific effect would require strong systematic controls. The description in the full text appears consistent and without internal problems, but the strength depends on the quality of those checks and the reported uncertainties. Readers who will get the most from this are those involved in the NEXT experiment or other high-pressure xenon detectors for neutrino physics. It provides practical calibration information that can improve modeling in similar setups. Overall, the work shows clear experimental thinking and honest reporting of the results. I would recommend sending it for peer review rather than a desk reject, as the measurements fill a specific gap even if the effect size is modest.

Referee Report

0 major / 2 minor

Summary. The manuscript presents measurements of the reduced electroluminescence yield (Y/p) in xenon gas using the NEXT-DEMO++ detector, a prototype TPC for the NEXT-100 experiment. Data were collected at pressures ranging from 2.0 to 9.4 bar using the 41.5 keV de-excitation peak of 83mKr. The yield was fitted to a linear model in E/p at each pressure, revealing a modest (~5%) variation in the slope that starts around 5 bar and increases with higher pressure. The work aims to clarify inconsistencies in the literature on the pressure dependence of the EL yield.

Significance. Should the observed pressure dependence prove to be a genuine physical effect rather than an artifact of detector systematics, this measurement would contribute to a better understanding of electroluminescence processes in high-pressure xenon. This is significant for optimizing the performance of xenon TPCs in searches for neutrinoless double beta decay, as accurate modeling of the EL yield affects energy resolution and event reconstruction. The direct experimental approach using a relevant prototype detector strengthens the applicability of the results.

minor comments (2)

[Abstract] Abstract: the description of the linear fit to the reduced yield reveals a ~5% slope change but does not quote the actual fitted slope values (with uncertainties) at the different pressures; providing these numbers would allow readers to judge the statistical significance of the reported variation.
[Abstract] Abstract: the pressure points at which data were taken (within 2.0–9.4 bar) and the number of independent measurements are not specified; adding this information would clarify how densely the trend with pressure was sampled.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their positive assessment of the manuscript and for recommending minor revision. No specific major comments were provided in the report, so we have no individual points to address here. We are prepared to incorporate any minor editorial or technical suggestions in the revised version.

Circularity Check

0 steps flagged

No significant circularity; direct measurement and post-hoc fit

full rationale

The manuscript describes direct experimental measurements of reduced EL yield Y/p versus E/p in a xenon TPC using the 41.5 keV 83mKr peak, performed at multiple pressures from 2 to 9.4 bar. Linear models are fitted to the data at each pressure, and a modest ~5% variation in the fitted slope is reported as a function of pressure. No derivation chain exists that reduces a claimed prediction or first-principles result to its own inputs by construction. No self-citations are invoked as load-bearing uniqueness theorems or ansatzes. The central claim is an empirical observation from calibration and fitting procedures that remain independent of the reported slope change. This is a standard experimental result with no internal reduction to fitted quantities.

Axiom & Free-Parameter Ledger

1 free parameters · 1 axioms · 0 invented entities

The central claim rests on the standard linear model for electroluminescence yield in noble gases and on experimental calibration using a known energy peak; no new entities are postulated.

free parameters (1)

slope of reduced EL yield Y/p
Fitted separately at each pressure to quantify the observed change.

axioms (1)

domain assumption Electroluminescence yield is linearly proportional to reduced electric field E/p
Invoked to fit the data and extract the pressure-dependent slope.

pith-pipeline@v0.9.0 · 6097 in / 1153 out tokens · 49347 ms · 2026-05-10T07:23:15.714058+00:00 · methodology

discussion (0)

Reference graph

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