Future studies can build on the DeepDive program

The gap

Evidence profile

Sourced from the limitations and future-work section and stated research gap of the source papers, classified as general, drawn from work published between 2024 and 2026, spanning 3 journals. Those papers have been cited 106 times in total.

Supporting evidence — 3 representative gaps

• Impact of Cosmic Filaments on Galaxy Morphological Evolution and Predictions of Early Cosmic Web Structure for Roman (2026) · The Astrophysical Journal · doi

  In Section 4, we presented some prospects for accurately mapping the early cosmic web with galaxy surveys with deep photometry and spectroscopy as would be enabled by Roman. The deepest emission line flux limits currently planned for the HLWAS would only be able to detect a very biased sample of massive and highly star-forming galaxies at z = 1, which cannot accurately trace the filamentary structure. By boosting the spectroscopic survey sensitivity, more representative tracer galaxy samples can be obtained. However, even the planned line flux limit of HLWAS-Deep is sufficient to identify most of the galaxy overdensities in the field. These specific regions can be spectroscopically followed up to reach a few times lower emission line flux limits, which represents a far more efficient and practically viable approach to map cosmic filaments than performing such observations over the entire HLWAS Deep or Ultra-deep fields. Generally, 2.5× deeper spectroscopy will enable a highly accurate and complete reconstruction of the z = 1 cosmic web, but increasing this depth 2-fold does not significantly improve the reconstruction. Assuming that galaxy shapes and spins can be accurately measured, such deep surveys would be able to qualitatively recover the dependence of galaxy morphological properties on filament densities. We present a fairly idealized analysis of the ability of highredshift galaxy surveys to reconstruct the cosmic web. We made several assumptions in this process (see the Appendix), and these will have different degrees of impact on the final reconstructed structure and its correlation with galaxy morphologies. Moreover, observational data is much more complex and uncertain to interpret than simulation snapshots. Accordingly, our predictions should be interpreted as the most optimistic scenarios for high-z cosmic web reconstruction from wide-field surveys on Roman and other state-of-the-art observatories. We discuss some of the uncertainties in our results stemming from the assumptions we made. One of the largest sources of uncertainty is the conversion from observational emission line flux limits to simulated SFRs. It is very challenging to generate detailed mock photometry of galaxies that self-consistently models the dust attenuation within each galaxy (e.g., D. Nelson et al. 2018; M. Donnari et al. 2019). This being beyond the scope of our paper, we simply assume that the dust attenuation in our simulated galaxies the population-averaged properties of observed z ∼ 1 galaxies (K. V. Nedkova et al. 2024) according to their stellar mass. If we instead allow the individual values to vary within the ±1σ confidence interval of the observations, the number of tracers in our mock samples does change. This change is within ≈10% for the HLWAS 2.5× Spec-Deep and 5× Spec-Deep samples, but the mass and SFR completeness limit the change by less than 10%. Consequently, cosmic web from these samples would not change reconstructions follows 22 The Astrophysical Journal, 1004:74 (28pp), 2026 June 10 Hasan et al. significantly from our fiducial results. In contrast, the number and completeness of tracers in the HLWAS Spec-Deep sample are much more sensitive to the assumed dust attenuation. Despite this, our conclusion that the HLWAS Spec-Deep sample cannot accurately reconstruct the cosmic web remains unchanged.

  generallimitationsevidence 5/5
  Keywords: deep galaxy cosmic hlwas accurately surveys line flux galaxies samples change spec emission limits sample
• DeepDive: A deep dive into the physics of the first massive quiescent galaxies in the Universe (2026) · Astronomy and Astrophysics · cited 1× · doi

  Future studies can build on the DeepDive program by using larger sample sizes and more advanced techniques. The program demonstrates the importance of medium-resolution NIRSpec spectroscopy for future studies. Future studies can use the results to inform models of galaxy evolution.

  generalfuture-work sectionevidence 5/5
  Keywords: future studies build deepdive program using larger sample
• Efficient formation of a massive quiescent galaxy at redshift 4.9 (2024) · Nature Astronomy · cited 105× · doi

  The lack of robust detections of early massive quiescent galaxies due to the coarse wavelength sampling of photometric surveys. The uncertainty in the formation mechanisms of massive galaxies in the early Universe. The need for spectroscopic confirmation of massive quiescent galaxies at high redshifts.

  generalstated research gapevidence 5/5
  Keywords: lack robust detections early massive quiescent galaxies due

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