REVIEW 4 major objections 5 minor 2 cited by
MUSE integral-field spectra confirm 48 candidate gravitational lenses from the DESI Legacy Surveys by measuring both lens and source redshifts.
Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →
T0 review · deepseek-v4-flash
2026-08-04 15:45 UTC pith:LHIHMIQ7
load-bearing objection Useful catalog paper with honest quality flags, but internal inconsistencies in counts and tables mean the published version needs correction before the 48-lens claim can be used as-is. the 4 major comments →
DESI Strong Lens Foundry IV: Spectroscopic Confirmation of DESI Lens Candidates with VLT/MUSE
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The paper reports that, of 75 lens candidates found by a neural network in the DESI Legacy Imaging Surveys, 48 are now spectroscopically confirmed gravitational lenses: MUSE spectra yielded measurable redshifts for both the foreground lens galaxy and the background source in each system. Twenty-one more candidates gave a lens redshift but no source redshift, and six were ruled out because the apparent arc had the same redshift as the adjacent galaxy. The confirmed sample spans lens redshifts z ~ 0.2–1.1 and source redshifts up to z ~ 3.5, and includes Einstein crosses, multiple source planes, and group/cluster-scale environments.
What carries the argument
The central instrument is the MUSE integral-field spectrograph, a camera that records a spectrum at every position in a 60×60 arcsecond field across 4750–9350 Å. The analysis extracts averaged 1D spectra from circular apertures or manually selected spaxels, then identifies rest-frame emission and absorption lines by eye to assign redshifts. A quality flag, Qz = 1 (robust), 2 (probable), or 3 (possible), records confidence. This machinery lets a single exposure confirm multiple lens components and detect weak high-redshift features that would be missed by single-fiber spectroscopy.
Load-bearing premise
The central assumption is that the spectral lines used to assign source redshifts—especially the weak, low-signal-to-noise features flagged Qz = 2 or 3—genuinely belong to the background source and are not noise, sky residuals, or contamination from a foreground object.
What would settle it
Take the systems whose source redshift depends on weak features, such as DESI J161.4114-08.8358 (source z = 2.08 from Fe II absorption, Qz = 3), and obtain deeper spectra with higher resolution; if the claimed weak lines do not appear with consistent wavelength and strength, or if an unresolved foreground component is revealed, the confirmed count of 48 would decrease.
If this is right
- The 48 confirmed systems with both lens and source redshifts are ready for gravitational-lens modeling, including mass profiles and dark-matter substructure studies.
- The sample demonstrates that MUSE can confirm complex lenses—multiple images, multiple source planes, group/cluster environments—in a single pointing.
- The six non-lenses show that imaging-based candidate selection needs spectroscopic screening before the sample is used statistically.
- High-redshift lensed sources, including one at z ≈ 3.5 with Ly-alpha emission, become targets for studying early galaxies.
- Combined with HST imaging and other spectroscopic follow-up in the same foundry series, these systems build toward larger samples for time-delay cosmography and dark-matter studies.
Where Pith is reading between the lines
- The manuscript's abstract and conclusion disagree on the headline numbers (55 systems from 223 spectra versus 48 systems from 185 spectra); this contradiction should be resolved before the sample is used as a catalog.
- Systems whose source redshift comes from weak, noisy features flagged Qz = 2 or 3 would benefit from independent deep follow-up; if those features do not reproduce, the confirmed count could shrink.
- A combined success rate of roughly two-thirds fully confirmed or lens-redshift-only out of 75 candidates suggests this machine-learning-plus-IFU strategy can scale to much larger candidate catalogs, though the paper does not quantify that scaling.
- The double-source-plane systems presented here may be particularly valuable for future lens modeling that probes dark matter in the foreground galaxy, an application the paper lists but does not carry out.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. This paper presents VLT/MUSE integral-field spectroscopy of strong gravitational lens candidates selected by a residual neural network from the DESI Legacy Imaging Surveys. The authors extract 1D spectra from MUSE data cubes, manually identify emission and absorption features, and compile a catalog of systems with measured redshifts. The central claim is that both lens and source redshifts were successfully measured for 48 gravitational lens systems, with an additional 21 lens-only systems and 6 confirmed non-lenses. Detailed figures and spectral descriptions are provided for each confirmed system, along with a quality-flag scheme (Qz = 1, 2, 3) for redshift confidence.
Significance. If the catalog is reliable, it is a valuable community resource: spectroscopically confirmed strong lenses with measured lens and source redshifts are relatively rare, and the southern-hemisphere focus complements HST, DESI, and Keck follow-up. The paper's strengths include the honest quality-flag system, the use of independent MUSE data to test machine-learning candidates, and the careful per-system spectral descriptions. However, the published version currently contains several internal inconsistencies, transcription errors, and a lack of redshift uncertainties that prevent independent verification of the headline claim. The central result is likely defensible after corrections, but the paper is not yet in a publishable state as a reference catalog.
major comments (4)
- [Abstract vs. Section 5] The abstract and Section 5 report 75 targets, 185 spectra, 48 confirmed lens systems, 21 lens-only systems, and 6 non-lenses. The abstract text supplied with the submission reports 76 targets, 223 spectra, 55 confirmed systems, 15 lens-only systems, and 6 non-lenses. These are irreconcilable. Since these summary statistics are the paper's main deliverable, this discrepancy must be resolved before publication.
- [Table 2, Table 3, Table 4] There are load-bearing transcription errors in the tables. In Table 2, the Source A and Source B coordinates for DESI J186.4036-07.4200 are identical to the Source A/B coordinates of DESI J168.7680+16.7604 (168.7687, +16.7590 and 168.7686, +16.7576), making it impossible for a reader to verify the extraction apertures for this system. In Table 3, the Arc coordinates for DESI-311.4249-10.6762 duplicate those of DESI-252.2720+02.3993. In Table 4, the R.A. for DESI-306.4726-51.2868 is listed as 306.2500, inconsistent with the target name. These are not cosmetic issues in a reference sample.
- [Section 3 and Table 2 (Qz = 3 systems)] The paper defines Qz = 3 as 'Possible' yet Section 5 counts all 48 systems with measured lens and source redshifts as 'fully confirmed'. Some of these systems rest entirely on Qz = 3 source redshifts with no quoted uncertainties. For example, DESI J343.0402-04.2187 has all four source components at z = 0.58 with Qz = 3 based on a faint [OII] doublet, and DESI J196.4575+22.9256 has a source at z = 0.713 with Qz = 3. A single incorrect line identification would remove a system from the confirmed sample. Either the headline count should distinguish secure from probable/possible systems, or the authors should provide quantitative redshift uncertainties and a clear criterion for what constitutes 'fully confirmed'.
- [Section 4.1 and Table 2 internal inconsistencies] There are internal discrepancies between the text and Table 2. For DESI J122.0852+10.5284, item 14 states that Source A has z = 2.2365, while Table 2 lists Source A as z = 1.2365 and Source B as z = 1.453. For DESI J218.2479-07.2268, item 29 says 'L2 at z = 0.338 and the fainter L1 at z = 0.84', whereas Table 2 lists Lens 1 at z = 0.338 and Lens 2 at z = 0.84, i.e., the labels are swapped. Item 22 also contains missing wavelengths ('S IIλÅ, C IVλÅ'). These inconsistencies directly affect the reliability of the published catalog.
minor comments (5)
- [Section 1] Typo: 'installed the ESO's Very Large Telescope' should read 'installed on the ESO's Very Large Telescope'.
- [Table 4 note] The table note defines Qz = 3 as 'Guess', while Section 3 defines Qz = 3 as 'Possible'. Please use one definition consistently.
- [Section 4.2] The descriptions of non-lenses refer to 'Figure 5' in several places, but the corresponding figures are numbered 49–54. Please update the cross-references.
- [References] The Cikota et al. 2023 reference appears twice with slightly different formatting. Please merge.
- [Section 3] The statement that the number of decimal places in Table 2 reflects 'the small range of variation' is not a substitute for quantitative redshift uncertainties. At minimum, please state the typical uncertainty or provide a method for estimating it from the spectra.
Circularity Check
No significant circularity: spectroscopic confirmation is an independent observational test of previously identified candidates.
full rationale
This paper is an observational follow-up paper, not a derivation. Its central claim — that 48 gravitational lens systems have both lens and source redshifts measured from new VLT/MUSE spectra — rests on new data, not on a re-use of fitted inputs. The authors state: "Redshifts for lenses and sources were obtained via manual identification of spectral features in extracted 1D spectra" (Section 3), and the 48-system count is presented as "successfully determining both the lens and the source redshifts for 48 gravitational lens systems" (Section 5). The lens candidates from the same group's earlier neural-network surveys are the target list, but the confirmation is carried by independent MUSE spectroscopy: extracted 1D spectra, identified emission/absorption lines, and stated quality flags (Qz = 1, 2, 3). There is no equation in which a fitted parameter is renamed as a prediction, no theorem imported from a self-citation that forces the result, and no ansatz smuggled in via citation. The Qz = 2/3 source redshifts are explicitly flagged as probable/possible, e.g., "A faint emission line is detected in the four components of the arc, exhibiting a double-peaked structure consistent with [OII] emission. This suggests a redshift of z = 0.58 for the background galaxy, with a quality flag of Qz = 3 due to the low SNR" (Desc. 46). That is an honest admission of measurement uncertainty, not circularity. Self-citations (Huang et al. 2020, 2021; Storfer et al. 2024; Cikota et al. 2023) are used to identify the candidate sample and to reference prior work on specific systems, but the confirmation claim does not reduce to those citations. Some systems are cross-checked against independent external literature or Keck data, but even without those, the MUSE spectra themselves are the load-bearing evidence. The duplicated source coordinates for DESI J186.4036-07.4200 in Table 2 are a transcription/verifiability defect, but they do not make the argument circular. Overall, the confirmation loop — machine-learning candidates followed by new spectroscopy — is a standard, non-circular validation procedure.
Axiom & Free-Parameter Ledger
axioms (3)
- domain assumption Rest-frame wavelengths of spectral features (e.g., O II 3727/3729, Ca II H&K, C IV) are known and correspond to the identified lines.
- domain assumption The arc/ring morphologies, after redshift ordering, indicate gravitational lensing rather than tidal debris or chance superpositions.
- domain assumption MUSE data reduction (pipeline 2.2 plus ZAP) yields accurate, sky-subtracted spectra.
read the original abstract
We present integral field spectroscopic observations of 76 strong gravitational lens candidates identified with a residual neural network in the DESI Legacy Imaging Surveys, obtained with the Multi Unit Spectroscopic Explorer (MUSE) on the ESO's Very Large Telescope. These observations are part of an ongoing effort to build a large, spectroscopically confirmed sample of strong lensing systems for studies on dark matter, galaxy structure, and cosmology. Our MUSE program targets both lens and source redshifts, with particular emphasis on southern hemisphere systems. MUSE's wide spectral coverage and integral field capability allow for efficient identification of multiple sources, lens environments, and weak spectral features. Redshifts for lenses and sources were obtained via manual identification of spectral features in extracted 1D spectra. Our dataset includes systems with complex configurations, such as multiple source planes and group or cluster-scale environments. We extracted and analyzed 223 spectra, successfully determining both the lens and the source redshifts for 55 gravitational lens systems. For an additional 15 targets, we measured the redshifts of the lenses but were unable to determine the redshifts of the background sources. Six targets were confirmed to not be gravitational lenses. The results presented here complement space-based imaging from our HST SNAPshot program and spectroscopic follow-up with DESI and Keck, and have lasting legacy value for identifying interesting high redshift sources and complex lensing configurations.
Figures
Forward citations
Cited by 2 Pith papers
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Investigating the Dark Energy Constraint from Strongly Lensed AGN at LSST-Scale
A simulated sample of 800 LSST lensed AGN, analyzed with a new hierarchical time-delay inference code, is forecast to yield ~2.5% H0 precision and a dark-energy figure of merit of 6.7 in w0waCDM.
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XShooter DESI Lens Program: Sample characterization
XShooter redshifts for 58 lenses and 57 sources from DESI Legacy Survey candidates show no measurement bias, so the source-z distribution can calibrate large imaging surveys.
Reference graph
Works this paper leans on
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Acebron, A., Grillo, C., Bergamini, P., et al. 2022, Astronomy & Astrophysics, 668, A142 Aghamousa, A., Aguilar, J., Ahlen, S., et al. 2016a, arXiv preprint arXiv:1611.00037 —. 2016b, arXiv preprint arXiv:1611.00037 Bacon, R., Accardo, M., Adjali, L., et al. 2010, in Ground-based and airborne instrumentation for astronomy III, Vol. 7735, SPIE, 131–139 Bol...
Pith/arXiv arXiv 2022
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[2]
N E 1.0
Spectroscopic Confirmation of DESI Lens Candidates 21 10.0 " N E 1.0 " N E L1 L2 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 6900 0 50 100 150 K H G band Hβ Mg b Na D DESI J043.6663-04.3068Galaxy z=0.344 L1 L2 1400 1600 1800 2000 2200 2400 2600 Rest frame wavelength (˚A) 10 20 30Flux Si IV Si IV + O IV Si II C IV Fe II Al II [C III] Fe II Figure
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22 Lin et al. 10.0 " N E 1.0 " N E A B 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600−50 0 50 100 150 K H G band Hβ Mg b Na D DESI J053.6251-13.1869 Galaxy z=0.387 1600 1800 2000 2200 2400 2600 2800 Rest frame wavelength (˚A) 10 20Flux Si II C IV Fe II Al II [C III] Al III Mg I Fe II Figure
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Spectroscopic Confirmation of DESI Lens Candidates 23 10.0 " N E 1.0 " N E 3000 3300 3600 3900 4200 4500 4800 5100 5400−20 0 20 K H G band Hβ Mg b DESI J055.0894-25.5581 Galaxy z=0.656 1400 1600 1800 2000 2200 2400 Rest Frame wavelength (˚A) −2 0 2 4 6 Flux OI+SiII C II Si IV Si IV + O IV [C III] [O III] Figure
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Spectroscopic Confirmation of DESI Lens Candidates 27 10.0 " N E 1.0 " N E Lens B AA 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600−50 0 50 100 150 O II K H Hβ O III O III Mg b Na D Hα S II DESI J073.9027-25.5132 Galaxy z=0.378 1400 1600 1800 2000 2200 2400 0 1 2 3 4Flux OI+SiII CII Si IV Si IV + O IV Si II C IV Fe II Al II [C III] Si II Al III Fe...
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28 Lin et al. 10.0 " N E 1.0 " N E 3300 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 0 20 40 60 80 K H G band Hβ Mg b Na D DESI J074.9646-30.7233 Galaxy z=0.441 2000 2200 2400 2600 2800 3000 3200 3400 3600 3800 Rest Frame wavelength (˚A) 0 10 20 30Flux O II 3700 3725 3750 3775 −10 0 10 20 30 40 O II Figure
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Spectroscopic Confirmation of DESI Lens Candidates 29 10.0 " N E 1.0 " N E 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 6900 0 50 K H G band Hβ Mg b Na D DESI J075.2793-24.4176 Galaxy z=0.32 1400 1600 1800 2000 2200 2400 Rest Frame wavelength (˚A) 0 1 2 3 4 5Flux OI+SiII CII Si IV Si IV + O IV Si II C IV Fe II Al II [C III] Fe II [O III] Figure
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30 Lin et al. 10.0 " N E 1.0 " N E L2 L1 A B C 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 6900 7200−50 0 50 100 150 200 250 300 K H G band Mg b Na D DESI J086.3072-26.5878 Lens Galaxy z= 0.275 L1 L2 1600 1800 2000 2200 2400 2600 2800 Rest frame wavelength (˚A) −20 0 20 40 Flux Si II C IV Fe II Al II [C III] Fe II [O III] A B C all Figure
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32 Lin et al. 10.0 " N E 8.0 " N E L1 L2 A B C D 3500 4000 4500 5000 5500 6000 0 50 K H G band Hβ Mg b Na D DESI J090 .9854 − 35.9683 Galaxy (L1) z =0.489 2000 2250 2500 2750 3000 3250 3500 3750 −10 0 10 20 30 40 50 Flux O II A B C D 3710 3715 3720 3725 3730 3735 3740 3745 −20 0 20 40 O IIO IIO IIO II Rest frame wavelength (˚A) Figure
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Spectroscopic Confirmation of DESI Lens Candidates 33 10.0 " N E 1.0 " N E A B 3300 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 0 10 20 30 K H G band Hβ Mg b DESI J122.0852+10.5284Lens Galaxy z=0.475 2200 2400 2600 2800 3000 3200 3400 3600 3800 4000 0 5 10Flux O II 3710 3720 3730 3740 3750−5 0 5 10 15 20 O II 2000 2200 2400 2600 2800 3000 3200 3400 ...
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34 Lin et al. 10.0 " N E 1.0 " N E A B 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 0 25 50 K H G band Mg b Na D DESI J154.6975-01.3588Lens Galaxy z= 0.389 2000 2200 2400 2600 2800 3000 3200 3400 3600 3800 0 20 40 60 80 100 120 140Flux O II A B 3710 3720 3730 3740 3750 −20 0 20 40 60 80 100 120 140 O IIO II Rest frame wavelength (˚A) Figure
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36 Lin et al. 10.0 " N E 4.0 " N E 3300 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 0 15 30 45 K H G band Hβ Mg b Na D DESI J157 .6135 − 06.6858 Galaxy z =0.466 1900 2000 2100 2200 2300 2400 2500 2600 2700 2800 2900 3000 −2 0 2 4 6 8 10 12 14 Flux Fe II Fe II Fe II Mg II 2300 2320 2340 2360 2380 2400 2420 2440 0 5 10 15 Fe II Fe II 2560 2580 2600 26...
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N E 2.0
38 Lin et al. 10.0 " N E 2.0 " N E A 2700 3000 3300 3600 3900 4200 4500 4800 5100−15 0 15 Mg II K H DESI J161 .4114 − 08.8359 Galaxy z =0.827 1600 1800 2000 2200 2400 2600 2800 3000 0 2 4 6 8 10Flux Fe II Fe II Mg II Rest frame wavelength (˚A) Figure
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40 Lin et al. 10.0 " N E 1.0 " N E B AA Main Lens L1 Foreground galaxy L2 3300 3600 3900 4200 4500 4800 5100 5400 5700 6000 −10 0 10 20 30 40 K H G band Hβ Mg b Na D DESI J168.7680+16.7604 Lens Galaxy L1 z=0.537 3300 3600 3900 4200 4500 4800 5100 5400 5700 6000 −10 0 10 20 K H G band Hβ Mg b Na D Foreground Galaxy L2 z=0.534 1600 1800 2000 2200 2400 2600 ...
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Spectroscopic Confirmation of DESI Lens Candidates 41 10.0 " N E 2.0 " N E A L 3300 3600 3900 4200 4500 4800 5100 5400 5700−20 0 20 40 K H G band Hβ Mg b Na D DESI J174 .5481 + 14.7863 Galaxy z =0.565 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 2600 2700 0 5 10 15Flux Si II C IV O III Al II Fe II Fe II 1450 1500 1550 1600 1650 1700 1750 0 ...
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Spectroscopic Confirmation of DESI Lens Candidates 43 10.0 " N E 1.0 " N E 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 6900 0 50 100 150 200 K H G band Hβ Mg b Na D Hα DESI J190.7935+21.3334Galaxy z =0.348 2000 2200 2400 2600 2800 3000 3200 3400 3600 0 20 40 60 80 100 120 140Flux O II 3720 3750 0 20 40 60 80 100 120 140 160 O II Rest frame wave...
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Spectroscopic Confirmation of DESI Lens Candidates 49 10.0 " N E 1.0 " N E A B C D 3000 3300 3600 3900 4200 4500 4800 5100 −20 0 20 40 K H G band O III Hβ Mg b DESI J220.4549+14.6891 Galaxy z=0.742 2000 2200 2400 2600 2800 3000 3200 3400 3600 3800−20 0 20 40 60 80 100 120 Flux O II A B C D 3700 3725 3750 0 20 40 60 80 100 120 A B C D O II A B C D O II A B...
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50 Lin et al. 10.0 " N E 1.0 " N E A B 3000 3300 3600 3900 4200 4500 4800 5100 5400 −10 −5 0 5 10 15 O II K H DESI J234.4780+14.7229 Lens Galaxy z=0.731 1400 1600 1800 2000 2200 2400 2600 −10 −5 0 5 10 15 Flux [C III] He II [O III] A B 1625 1650 1675 0 15 A B He II [O III] 1890 1920 1950−10 −5 0 5 10 15 20 A B [C III] Rest frame wavelength (˚A) Figure
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N E 1.0
Spectroscopic Confirmation of DESI Lens Candidates 51 10.0 " N E 1.0 " N E A B 2700 3000 3300 3600 3900 4200 4500 4800 5100−10 0 10 20 O II K H G band Hβ Mg b DESI J238.5690+04.7276Lens Galaxy z=0.777 1800 2000 2200 2400 2600 2800 3000 3200 3400−2 0 2 4 6 8 10 12 14 16 Flux [C III] Al III Fe II A B 1830 1860 1890−10 −5 0 5 10 15 20 A B Al III 1890 1920 19...
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52 Lin et al. 10.0 " N E 2.0 " N E L1 L2 3000 3300 3600 3900 4200 4500 4800 5100 0 50 K H G band Hβ Mg b DESI J245 .7514 + 21.6226 Galaxy (L1) z =0.757 1800 1900 2000 2100 2200 2300 2400 2500 2600 2700 2800 2900 3000 3100 3200 3300 3400 0 2 4 6 8 10 12Flux C III Fe II Fe IIFe II Mg II 1860 1890 1920 1950 0 3 6 9 C III 2320 2360 2400 2440 0 3 6 9 Fe II Fe ...
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Spectroscopic Confirmation of DESI Lens Candidates 53 10.0 " N E 1.0 " N E bottom left toptop G1 G2 G3 G4 2400 2700 3000 3300 3600 3900 4200 0 10 K H G band DESI J246.0068+01.4842 Lens Galaxy z=1.092 1600 1800 2000 2200 2400 2600 0 2 4 6 8 10 12Flux Si II C IV Fe II Al II Al III Fe II all combined top bottom left 2400 2600 2800 3000 3200 3400 3600 3800 40...
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N E 2.0
54 Lin et al. 10.0 " N E 2.0 " N E A B C D 3000 3500 4000 4500 5000 5500 0 10 K H O II G band Hβ Mg b DESI J253 .2534 + 26.8843 Galaxy z = 0 .636 1500 2000 2500−10 0 10 20 30 40 50 Flux C II Si IV Si IV + O IV Si II C IV Fe II O III Al II C III A B C D 1320 1350 1380 1410 1440 0 10 20 30 40 50 A B C D C II Si IV Si IV + O IV A B C D C II Si IV Si IV + O I...
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[39]
N E 1.0
Spectroscopic Confirmation of DESI Lens Candidates 59 10.0 " N E 1.0 " N E B D A C 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 6900 7200 0 50 100 K H G band Hβ Mg b Na D DESI J329.6820+02.9584 Galaxy z=0.287 1600 1800 2000 2200 2400 2600 2800 3000 Rest frame wavelength (˚A) 0 10 20 30 40Flux C IV Fe II Al II [C III] Al III Fe II Mg II A B C D Figure
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N E 1.0
Spectroscopic Confirmation of DESI Lens Candidates 61 10.0 " N E 1.0 " N E arc L1 L2 L3 A B C 3300 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300−25 0 25 50 75 100 125 150 K H G band Mg b DESI J335.5354+27.7596Lens Galaxies z=0.49 L1 L2 L3 1600 1800 2000 2200 2400 2600 2800−5 0 5 10 15 Flux Si II C IV Fe II [O III] [C III] Si II Al III Fe II Fe II Mg I...
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N E 1.0
Spectroscopic Confirmation of DESI Lens Candidates 67 10.0 " N E 1.0 " N E X A1 A2 B1 B2 B3 B4 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 6900 7200 0 50 100 150 K H G band Hβ Mg b Na D DESI J345.8606+23.4757 Lens Galaxy z=0.276 3800 4000 4200 4400 4600 4800 5000 5200 5400 5600 5800 6000 6200 6400 6600 6800 7000 7200 0 2 4 6 8 K H G band Hγ OIII 220...
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discussion (0)
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