TY - JOUR
T1 - Compact to extended Lyman-α emitters in MAGPI
T2 - Strong blue-peak emission at z & 3
AU - Mukherjee, T.
AU - Zafar, T.
AU - Nanayakkara, T.
AU - Wisnioski, E.
AU - Battisti, A.
AU - Gupta, A.
AU - Lagos, C. D.P.
AU - Harborne, K. E.
AU - Foster, C.
AU - Mendel, T.
AU - Croom, S. M.
AU - Mailvaganam, A.
AU - Prathap, J.
N1 - Funding Information:
Acknowledgements. We wish to thank the ESO staff, and in particular the staff at Paranal Observatory, for carrying out the MAGPI observations. MAGPI targets were selected from GAMA. GAMA is a joint European-Australasian project based around a spectroscopic campaign using the Anglo-Australian Telescope. GAMA was funded by the STFC (UK), the ARC (Australia), the AAO, and the participating institutions. GAMA photometry is based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 179.A-2004, ID 177.A-3016. The MAGPI team acknowledges support from the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013.
Funding Information:
We wish to thank the ESO staff, and in particular the staff at Paranal Observatory, for carrying out the MAGPI observations. MAGPI targets were selected from GAMA. GAMA is a joint European-Australasian project based around a spectroscopic campaign using the Anglo-Australian Telescope. GAMA was funded by the STFC (UK), the ARC (Australia), the AAO, and the participating institutions. GAMA photometry is based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 179.A-2004, ID 177.A-3016. The MAGPI team acknowledges support from the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013.
Publisher Copyright:
c The Authors 2023.
PY - 2023/12/11
Y1 - 2023/12/11
N2 - We report the discovery of three double-peaked Lyman-α emitters (LAEs) exhibiting strong blue-peak emission at 2.9 . z . 4.8 in the VLT/MUSE data obtained as part of the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey. These strong blue-peak systems provide a unique window into the scattering of Lyα photons by neutral hydrogen (H i), suggesting gas inflows along the line of sight and low H i column density. Two of them at z = 2.9 and z = 3.6, are spatially extended halos with their core regions clearly exhibiting stronger emission at the blue peak than at the red peak. However, spatial variations in the peak ratio and peak separation are evident over 25 × 26 kpc (z = 2.9) and 19 × 28 kpc (z = 3.6) regions in these extended halos. Notably, these systems do not fall in the regime of Lyα blobs or nebulae. To the best of our knowledge, such a Lyα halo with a dominant blue core has not been observed previously. In contrast, the LAE at z ∼ 4.8 is a compact system spanning a 9 × 9 kpc region and stands as the highest-redshift strong blue-peak emitter ever detected. The peak separation of the bright cores in these three systems ranges from ∆peak ∼ 370 to 660 km s−1. The observed overall trend of decreasing peak separation with increasing radius is supposed to be controlled by H i column density and gas covering fraction. Based on various estimations, in contrast to the compact LAE, our halos are found to be good candidates for Lyman-continuum (LyC) leakers. These findings shed light on the complex interplay between Lyα emission, gas kinematics, and ionizing radiation properties, offering valuable insights into the evolution and nature of high-redshift galaxies.
AB - We report the discovery of three double-peaked Lyman-α emitters (LAEs) exhibiting strong blue-peak emission at 2.9 . z . 4.8 in the VLT/MUSE data obtained as part of the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey. These strong blue-peak systems provide a unique window into the scattering of Lyα photons by neutral hydrogen (H i), suggesting gas inflows along the line of sight and low H i column density. Two of them at z = 2.9 and z = 3.6, are spatially extended halos with their core regions clearly exhibiting stronger emission at the blue peak than at the red peak. However, spatial variations in the peak ratio and peak separation are evident over 25 × 26 kpc (z = 2.9) and 19 × 28 kpc (z = 3.6) regions in these extended halos. Notably, these systems do not fall in the regime of Lyα blobs or nebulae. To the best of our knowledge, such a Lyα halo with a dominant blue core has not been observed previously. In contrast, the LAE at z ∼ 4.8 is a compact system spanning a 9 × 9 kpc region and stands as the highest-redshift strong blue-peak emitter ever detected. The peak separation of the bright cores in these three systems ranges from ∆peak ∼ 370 to 660 km s−1. The observed overall trend of decreasing peak separation with increasing radius is supposed to be controlled by H i column density and gas covering fraction. Based on various estimations, in contrast to the compact LAE, our halos are found to be good candidates for Lyman-continuum (LyC) leakers. These findings shed light on the complex interplay between Lyα emission, gas kinematics, and ionizing radiation properties, offering valuable insights into the evolution and nature of high-redshift galaxies.
KW - cosmology: observations
KW - galaxies: evolution
KW - galaxies: high-redshift
UR - http://www.scopus.com/inward/record.url?scp=85180296714&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/202348202
DO - 10.1051/0004-6361/202348202
M3 - Article
AN - SCOPUS:85180296714
SN - 0004-6361
VL - 680
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
M1 - L5
ER -