TY - JOUR
T1 - JADES Possible Population III signatures at z = 10.6 in the halo of GN-z11
AU - Maiolino, Roberto
AU - Übler, Hannah
AU - Perna, Michele
AU - Scholtz, Jan
AU - D’Eugenio, Francesco
AU - Witten, Callum
AU - Laporte, Nicolas
AU - Witstok, Joris
AU - Carniani, Stefano
AU - Tacchella, Sandro
AU - Baker, William M.
AU - Arribas, Santiago
AU - Nakajima, Kimihiko
AU - Eisenstein, Daniel J.
AU - Bunker, Andrew J.
AU - Charlot, Stéphane
AU - Cresci, Giovanni
AU - Curti, Mirko
AU - Curtis-Lake, Emma
AU - de Graaff, Anna
AU - Egami, Eiichi
AU - Ji, Zhiyuan
AU - Johnson, Benjamin D.
AU - Kumari, Nimisha
AU - Looser, Tobias J.
AU - Maseda, Michael
AU - Nelson, Erica
AU - Robertson, Brant
AU - Del Pino, Bruno Rodríguez
AU - Sandles, Lester
AU - Simmonds, Charlotte
AU - Smit, Renske
AU - Sun, Fengwu
AU - Venturi, Giacomo
AU - Williams, Christina C.
AU - Willmer, Christopher N.A.
N1 - Publisher Copyright:
© The Authors 2024.
PY - 2024/7/1
Y1 - 2024/7/1
N2 - Finding the first generation of stars formed out of pristine gas in the early Universe, known as Population III (PopIII) stars, is one of the most important goals of modern astrophysics. Recent models have suggested that PopIII stars may form in pockets of pristine gas in the halo of more evolved galaxies. We present NIRSpec integral field spectroscopy and micro-shutter array spectroscopic observations of the region around GNz11, an exceptionally luminous galaxy at z = 10.6, that reveal a greater than 5σ detection of a feature consistent with being HeIIλ1640 emission at the redshift of GN-z11. The very high equivalent width of the putative HeII emission in this clump (log (EWrest(HeII)/Å) = 1.79+−001525) and a lack of metal lines can be explained in terms of photoionisation by PopIII stars, while photoionisation by PopII stars is inconsistent with the data. The high equivalent width would also indicate that the putative PopIII stars likely have an initial mass function with an upper cutoff reaching at least 500 M . The PopIII bolometric luminosity inferred from the HeII line would be ∼7 × 109 L , which would imply a total stellar mass formed in the burst of ∼2 × 105 M . We find that photoionisation by the active galactic nucleus (AGN) in GN-z11 cannot account for the HeII luminosity observed in the clump but can potentially be responsible for an additional HeII emission observed closer to GN-z11. We also consider the possibility of in situ photoionisation by an accreting direct collapse black hole hosted by the HeII clump. We find that this scenario is less favoured, but it remains a possible alternative interpretation. We also report the detection of a Lyα halo stemming out of GN-z11 and extending out to ∼2 kpc as well as resolved funnel-shaped CIII emission likely tracing the ionisation cone of the AGN.
AB - Finding the first generation of stars formed out of pristine gas in the early Universe, known as Population III (PopIII) stars, is one of the most important goals of modern astrophysics. Recent models have suggested that PopIII stars may form in pockets of pristine gas in the halo of more evolved galaxies. We present NIRSpec integral field spectroscopy and micro-shutter array spectroscopic observations of the region around GNz11, an exceptionally luminous galaxy at z = 10.6, that reveal a greater than 5σ detection of a feature consistent with being HeIIλ1640 emission at the redshift of GN-z11. The very high equivalent width of the putative HeII emission in this clump (log (EWrest(HeII)/Å) = 1.79+−001525) and a lack of metal lines can be explained in terms of photoionisation by PopIII stars, while photoionisation by PopII stars is inconsistent with the data. The high equivalent width would also indicate that the putative PopIII stars likely have an initial mass function with an upper cutoff reaching at least 500 M . The PopIII bolometric luminosity inferred from the HeII line would be ∼7 × 109 L , which would imply a total stellar mass formed in the burst of ∼2 × 105 M . We find that photoionisation by the active galactic nucleus (AGN) in GN-z11 cannot account for the HeII luminosity observed in the clump but can potentially be responsible for an additional HeII emission observed closer to GN-z11. We also consider the possibility of in situ photoionisation by an accreting direct collapse black hole hosted by the HeII clump. We find that this scenario is less favoured, but it remains a possible alternative interpretation. We also report the detection of a Lyα halo stemming out of GN-z11 and extending out to ∼2 kpc as well as resolved funnel-shaped CIII emission likely tracing the ionisation cone of the AGN.
KW - dark ages, reionization, first stars
KW - galaxies: active
KW - galaxies: high-redshift
KW - galaxies: individual: GN-z11
KW - stars: Population II
KW - stars: Population III
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UR - http://www.scopus.com/inward/citedby.url?scp=85191568162&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/202347087
DO - 10.1051/0004-6361/202347087
M3 - Article
AN - SCOPUS:85191568162
SN - 0004-6361
VL - 687
JO - Astronomy and astrophysics
JF - Astronomy and astrophysics
M1 - A67
ER -