---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
PlanS_conform: '1'
_id: '21063'
abstract:
- lang: eng
text: "We report the detection of a 13σ Hα emission line from HDF850.1 at z = 5.188
± 0.001 using the FRESCO (First Reionization Era SpectroscopicallyComplete Observations)
NIRCam F444W grism observations. Detection of Hα in HDF850.1 is noteworthy, given
its high far-infrared (IR) luminosity, substantial dust obscuration, and the historical
challenges in deriving its redshift.\r\nHDF850.1 shows a clear detection in the
F444W imaging data, distributed between a northern and southern component, mirroring
that seen in [C II] from the Plateau de Bure Interferometer. Modelling the spectral
energy distribution of each component separately, we find that the northern component
has a higher mass, star formation rate (SFR), and dust extinction than the southern
component. The observed Hα emission appears to arise entirely from the less-obscured
southern component and shows a similar \x04v∼ + 130 km s −1 velocity offset to
that seen for [C II] relative to the source systemic redshift. Leveraging Hα-derived
redshiftsfrom FRESCO observations, we find that HDF850.1 isforming in one of the
richest environments identified to date at z > 5, with 100 z = 5.17–5.20 galaxies
distributed across 13 smaller structures and a ∼(15 cMpc)3 volume. Based on the
evolution of analogous structures in cosmological simulations, the z = 5.17–5.20
structures seem likely to collapse into\r\na single > 1014M cluster by z ∼ 0.
Comparing galaxy properties forming within this overdensity with those outside,
we find the masses, SFRs, and UV luminosities inside the overdensity to be clearly
higher. The prominence of Hα line emission from HDF850.1 and other known highly
obscured z > 5 galaxies illustrates the potential of NIRCam-grism programs to
map both\r\nthe early build-up of IR-luminous galaxies and overdense structures."
acknowledgement: "We are grateful to Roberto Neri and collaborators for providing
us with spatially resolved information on both the dust-continuum and [C ii] line
emission from their high spatial resolution PdBI observations. This project was
made possible in part by the Leiden University Fund/Bouwens Astrophysics Fund. RJB
acknowledges support from NWO grants 600.065.140.11N211 (vrij competitie) and TOP
grant TOP1.16.057. The Cosmic Dawn Center (DAWN) is funded by the Danish National
Research Foundation under grant no. 140. Cloud-based data processing and file storage
for this work is provided by the AWS Cloud Credits for Research program. Support
for this work was provided by NASA through grant JWST-GO-01895 awarded by the Space
Telescope Science Institute, which is operated by the Association of Universities
for Research in Astronomy, Inc., under NASA contract NAS 5–26555. RPN acknowledges
funding from JWST programs GO-1933 and GO-2279. Support for this work was provided
by NASA through the NASA Hubble Fellowship grant HST-HF2-51515.001-A awarded by
the Space Telescope Science Institute, which is operated by the Association of Universities
for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. MS acknowledges
support from the CIDEGENT/2021/059 grant, from project PID2019-109592GB-I00/AEI/10.13039/501100011033
from the Spanish Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación.
This study forms part of the Astrophysics and High Energy Physics programme and
was supported by MCIN with funding from European Union NextGenerationEU (PRTR-C17.I1)
and by Generalitat Valenciana under the project n. ASFAE/2022/025. RAM acknowledges
support from the ERC Advanced Grant 740246 (Cosmic_Gas) and the Swiss National Science
Foundation through project grant 200020_207349.\r\n\r\nThis work is based on observations
made with the NASA/ESA/CSA JWST. The data were obtained from the Mikulski Archive
for Space Telescopes at the Space Telescope Science Institute, which is operated
by the Association of Universities for Research in Astronomy, Inc., under NASA contract
NAS 5–03127 for JWST. These observations are associated with program no. 1895.\r\n\r\nThis
paper made use of several publicly available software packages. We are indebted
to the respective authors for their work: ipython (Pérez & Granger 2007), matplotlib
(Hunter 2007), numpy (Oliphant 2006), scipy (Virtanen et al. 2020), jupyter (Kluyver
et al. 2016), astropy (Astropy Collaboration 2013, 2018), grizli (v1.7.11; Brammer
2018; Brammer et al. 2022), eazy (Brammer, van Dokkum & Coppi 2008), and SExtractor
(Bertin & Arnouts 1996)."
article_processing_charge: Yes
article_type: original
arxiv: 1
author:
- first_name: Thomas
full_name: Herard-Demanche, Thomas
last_name: Herard-Demanche
- first_name: Rychard J
full_name: Bouwens, Rychard J
last_name: Bouwens
- first_name: Pascal A
full_name: Oesch, Pascal A
last_name: Oesch
- first_name: Rohan P
full_name: Naidu, Rohan P
last_name: Naidu
- first_name: Roberto
full_name: Decarli, Roberto
last_name: Decarli
- first_name: Erica J
full_name: Nelson, Erica J
last_name: Nelson
- first_name: Gabriel
full_name: Brammer, Gabriel
last_name: Brammer
- first_name: Andrea
full_name: Weibel, Andrea
last_name: Weibel
- first_name: Mengyuan
full_name: Xiao, Mengyuan
last_name: Xiao
- first_name: Mauro
full_name: Stefanon, Mauro
last_name: Stefanon
- first_name: Fabian
full_name: Walter, Fabian
last_name: Walter
- first_name: Jorryt J
full_name: Matthee, Jorryt J
id: 7439a258-f3c0-11ec-9501-9df22fe06720
last_name: Matthee
orcid: 0000-0003-2871-127X
- first_name: Romain A
full_name: Meyer, Romain A
last_name: Meyer
- first_name: Stijn
full_name: Wuyts, Stijn
last_name: Wuyts
- first_name: Naveen
full_name: Reddy, Naveen
last_name: Reddy
- first_name: Lucie
full_name: Rowland, Lucie
last_name: Rowland
- first_name: Ivana
full_name: van Leeuwen, Ivana
last_name: van Leeuwen
- first_name: Pablo Arrabal
full_name: Haro, Pablo Arrabal
last_name: Haro
- first_name: Helmut
full_name: Dannerbauer, Helmut
last_name: Dannerbauer
- first_name: Alice E
full_name: Shapley, Alice E
last_name: Shapley
- first_name: John
full_name: Chisholm, John
last_name: Chisholm
- first_name: Pieter
full_name: van Dokkum, Pieter
last_name: van Dokkum
- first_name: Ivo
full_name: Labbe, Ivo
last_name: Labbe
- first_name: Garth
full_name: Illingworth, Garth
last_name: Illingworth
- first_name: Daniel
full_name: Schaerer, Daniel
last_name: Schaerer
- first_name: Irene
full_name: Shivaei, Irene
last_name: Shivaei
citation:
ama: 'Herard-Demanche T, Bouwens RJ, Oesch PA, et al. Mapping dusty galaxy growth
at z > 5 with FRESCO: Detection of Hα in submm galaxy HDF850.1 and the surrounding
overdense structures. Monthly Notices of the Royal Astronomical Society.
2025;537(2):788-808. doi:10.1093/mnras/staf030'
apa: 'Herard-Demanche, T., Bouwens, R. J., Oesch, P. A., Naidu, R. P., Decarli,
R., Nelson, E. J., … Shivaei, I. (2025). Mapping dusty galaxy growth at z >
5 with FRESCO: Detection of Hα in submm galaxy HDF850.1 and the surrounding overdense
structures. Monthly Notices of the Royal Astronomical Society. Oxford University
Press. https://doi.org/10.1093/mnras/staf030'
chicago: 'Herard-Demanche, Thomas, Rychard J Bouwens, Pascal A Oesch, Rohan P Naidu,
Roberto Decarli, Erica J Nelson, Gabriel Brammer, et al. “Mapping Dusty Galaxy
Growth at z > 5 with FRESCO: Detection of Hα in Submm Galaxy HDF850.1 and
the Surrounding Overdense Structures.” Monthly Notices of the Royal Astronomical
Society. Oxford University Press, 2025. https://doi.org/10.1093/mnras/staf030.'
ieee: 'T. Herard-Demanche et al., “Mapping dusty galaxy growth at z >
5 with FRESCO: Detection of Hα in submm galaxy HDF850.1 and the surrounding overdense
structures,” Monthly Notices of the Royal Astronomical Society, vol. 537,
no. 2. Oxford University Press, pp. 788–808, 2025.'
ista: 'Herard-Demanche T, Bouwens RJ, Oesch PA, Naidu RP, Decarli R, Nelson EJ,
Brammer G, Weibel A, Xiao M, Stefanon M, Walter F, Matthee JJ, Meyer RA, Wuyts
S, Reddy N, Rowland L, van Leeuwen I, Haro PA, Dannerbauer H, Shapley AE, Chisholm
J, van Dokkum P, Labbe I, Illingworth G, Schaerer D, Shivaei I. 2025. Mapping
dusty galaxy growth at z > 5 with FRESCO: Detection of Hα in submm galaxy
HDF850.1 and the surrounding overdense structures. Monthly Notices of the Royal
Astronomical Society. 537(2), 788–808.'
mla: 'Herard-Demanche, Thomas, et al. “Mapping Dusty Galaxy Growth at z > 5
with FRESCO: Detection of Hα in Submm Galaxy HDF850.1 and the Surrounding Overdense
Structures.” Monthly Notices of the Royal Astronomical Society, vol. 537,
no. 2, Oxford University Press, 2025, pp. 788–808, doi:10.1093/mnras/staf030.'
short: T. Herard-Demanche, R.J. Bouwens, P.A. Oesch, R.P. Naidu, R. Decarli, E.J.
Nelson, G. Brammer, A. Weibel, M. Xiao, M. Stefanon, F. Walter, J.J. Matthee,
R.A. Meyer, S. Wuyts, N. Reddy, L. Rowland, I. van Leeuwen, P.A. Haro, H. Dannerbauer,
A.E. Shapley, J. Chisholm, P. van Dokkum, I. Labbe, G. Illingworth, D. Schaerer,
I. Shivaei, Monthly Notices of the Royal Astronomical Society 537 (2025) 788–808.
date_created: 2026-01-28T15:25:53Z
date_published: 2025-02-01T00:00:00Z
date_updated: 2026-02-09T08:50:55Z
day: '01'
ddc:
- '520'
department:
- _id: JoMa
doi: 10.1093/mnras/staf030
external_id:
arxiv:
- '2309.04525'
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page: 788-808
publication: Monthly Notices of the Royal Astronomical Society
publication_identifier:
eissn:
- 1365-2966
issn:
- 0035-8711
publication_status: published
publisher: Oxford University Press
quality_controlled: '1'
status: public
title: 'Mapping dusty galaxy growth at z > 5 with FRESCO: Detection of Hα in submm
galaxy HDF850.1 and the surrounding overdense structures'
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