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This content will become publicly available on February 1, 2026

Title: MeerKAT HI imaging of the jellyfish galaxy ESO 137-001
We present MeerKAT H Iobservations of ESO 137-001, a quintessential jellyfish galaxy with long multi-phase tails formed due to the interaction with the intra-cluster medium of its host galaxy cluster, ACO 3627. Our observations reveal the presence of H Iin both the disc and outer regions of the galaxy for the first time, with a total H Imass of (3.5 ± 0.4)×108M⊙. ESO 137-001 is at an advanced stage of gas stripping; it is extremely H Ideficient and seems to have lost 90% of its initial H Imass; about 2/3 of the surviving H Iis found at larger radius than expected for a normal H Idisc and forms ∼40 kpc tail coincident with the tail detected at other wavelengths. Only ∼10% of the surviving H Iis still found within the stellar disc, consistent with the expectation of an outside-in truncation due to ram pressure. Similarly to other jellyfish galaxies, ESO137-001 has a high star formation rate for the low amount of H Idetected. We measure an H Idepletion time of 0.29 Gyr. However, when taking into account the total gas (H I+ H2) content, the depletion time is consistent with typical values measured in nearby spiral galaxies. This suggests that ESO 137-001 is at its current stage of ram pressure interaction characterised by an efficient H Istripping, rather than an enhanced conversion of H Ito H2, which was recently observed in some other jellyfish galaxies.  more » « less
Award ID(s):
2407821
PAR ID:
10629721
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
EDP Sciences
Date Published:
Journal Name:
Astronomy & Astrophysics
Volume:
694
ISSN:
0004-6361
Page Range / eLocation ID:
A159
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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