Life beyond 30: Probing the −20 < M _UV < −17 Luminosity Function at 8 < z < 13 with the NIRCam Parallel Field of the MIRI Deep Survey

Abstract

We present the ultraviolet luminosity function and an estimate of the cosmic star formation rate density at 8 &lt; z &lt; 13 derived from deep NIRCam observations taken in parallel with the MIRI Deep Survey of the Hubble Ultra Deep Field (HUDF), NIRCam covering the parallel field 2. Our deep (40 hr) NIRCam observations reach an F277W magnitude of 30.8 (5σ), more than 2 mag deeper than JWST public data sets already analyzed to find high-redshift galaxies. We select a sample of 44 z &gt; 8 galaxy candidates based on their dropout nature in the F115W and/or F150W filters, a high probability for their photometric redshifts, estimated with three different codes, being at z &gt; 8, good fits based on χ 2 calculations, and predominant solutions compared to z &lt; 8 alternatives. We find mild evolution in the luminosity function from z ∼ 13 to z ∼ 8, i.e., only a small increase in the average number density of ∼0.2 dex, while the faint-end slope and absolute magnitude of the knee remain approximately constant, with values α = − 2.2 ± 0.1, and M * = − 20.8 ± 0.2 mag. Comparing our results with the predictions of state-of-the-art galaxy evolution models, we find two main results: (1) a slower increase with time in the cosmic star formation rate density compared to a steeper rise predicted by models; (2) nearly a factor of 10 higher star formation activity concentrated in scales around 2 kpc in galaxies with stellar masses ∼108 M ⊙ during the first 350 Myr of the universe, z ∼ 12, with models matching better the luminosity density observational estimations ∼150 Myr later, by z ∼ 9.

A Large Population of Faint 8 < z < 16 Galaxies Found in the First JWST NIRCam Observations of the NGDEEP Survey

“…5 We show the distribution of (aperture-corrected) F277W aperture magnitudes for our sample in Figure 4. What we find is that many of our new galaxies are fainter than other previous photometric candidates, with the exception of those by Pérez-González et al (2023). This is already revealing that these systems are of a different nature than the brighter galaxies seen in many previous surveys.…”

“…The NIRCam NGDEEP observations are not the first to be conducted in the HUDF-Par2 field. The MIRI Deep Survey (PID: 1283; PI's Hans Ulrik Nrgaard-Nielsen, Göran Östlin) has conducted a four-band NIRCam survey to depths just deeper than magnitude 30, reporting 45 candidate high-z galaxies (Pérez-González et al 2023). We find that only one of these galaxies enters our final sample, largely due to the low luminosities of the Pérez-González et al (2023) sample failing our 5σ selection criteria with very poor SED fits.…”

“…However, JWST has a primary mirror that is over 2.5 times larger in diameter that that of HST. This provides an ability to probe deeper in the universe than Hubble and thus far has been an aspect of the parameter space that has not been explored in any detail beyond examples of gravitational lensing (e.g., Bhatawdekar et al 2019;Diego et al 2023;Hsiao et al 2023;Pascale et al 2022) or the limited publications from ultradeep GTO programs (e.g., Robertson et al 2023;Curtis-Lake et al 2023;Pérez-González et al 2023). However, the NGDEEP project, which contains a deep NIRCam pointing of one of the Hubble Ultra Deep Field (HUDF) parallel fields, provides the first opportunity to explore the universe at an intrinsic depth greater than what Hubble has done to date.…”

MIDIS: Strong (Hβ+[O iii]) and Hα Emitters at Redshift z ≃ 7–8 Unveiled with JWST NIRCam and MIRI Imaging in the Hubble eXtreme Deep Field

“…In this plot, we show our own estimation of the SFRD, along with a compilation of recent results from the literature based on different SFR tracers. In particular, we also show the SFRD values that have recently been obtained by Bouwens et al (2023) using JWST data, tracing the SFR directly from the UV continuum emission at z ; 9 to z ; 15 as well as Pérez-González et al (2023) results at z ; 8-13 from ultradeep NIRCam images in HUDF-P2 (PID proposal: 1283, PI: Göran Östlin). Our inferred SFRD appears to be in good agreement with what has been found in the literature at similar redshifts.…”

“…For the nonemitters, the SFR directly comes from the UV continuum emission. Other symbols refer to the recent SFRD determinations from the literature, based on different SFR tracers (Schiminovich et al 2005;Kajisawa et al 2010;Burgarella et al 2013;Gruppioni et al 2013;Sobral et al 2014;Bouwens et al 2015;Rowan-Robinson et al 2016;Caputi et al 2017;Ishigaki et al 2018;Bouwens et al 2020;Gruppioni et al 2020;Loiacono et al 2021;Bouwens et al 2023;Rinaldi et al 2022;Pérez-González et al 2023). The different curves correspond to theoretical predictions.…”