Detection of HI 21 cm emission from a strongly lensed galaxy at z~1.3

Abstract

We report the first $5\sigma$ detection of HI 21 cm emission from a star-forming galaxy at redshift $z\sim 1.3$ (nearly 9 billion years ago) using upgraded Giant Metrewave Radio Telescope (uGMRT). This is the highest redshift HI detection in emission from an individual galaxy to date. The emission is strongly boosted by the gravitational lens, an early type elliptical galaxy, at redshift $z\sim 0.13$. The measured HI mass of the galaxy is ${\mathrm{M}}_{\mathrm{HI}}=(0.90\pm 0.14\pm 0.05)\times 10^{10}{\mathrm{M}}_{\odot }$, which is almost twice the inferred stellar mass of the galaxy, indicating an extended structure of the HI gas inside the galaxy. By fitting two-dimensional Gaussian to the HI signal at the peak of the spectral line, we find the source to be marginally resolved with the position angle consistent with the emission being tangential to the critical curve of the lens mass distribution. This indicates that the solid angle of the approaching HI line flux comes very close to the inner lens caustic and results in very high magnification. These results, for the first time, demonstrate the feasibility of observing high redshift HI in a lensed system with a modest amount of telescope time and open up exciting new possibilities for probing the cosmic evolution of neutral gas with existing and upcoming low-frequency radio telescopes in the near future.

Accepted for publication in MNRAS. There are 8 pages, 1 table and 6 figures

References in corpus (12)

• Cosmic Star Formation History
• WSClean: an implementation of a fast, generic wide-field imager for radio astronomy
• The non-coplanar baselines effect in radio interferometry: The W-Projection algorithm
• An optimized algorithm for multi-scale wideband deconvolution of radio astronomical images
• The Evolution of the Baryons Associated with Galaxies Averaged over Cosmic Time and Space
• Variation of galactic cold gas reservoirs with stellar mass
• The Sloan Lens ACS Survey. XIII. Discovery of 40 New Galaxy-Scale Strong Lenses
• The Sloan Lens ACS Survey. XII. Extending Strong Lensing to Lower Masses
• HI 21-centimetre emission from an ensemble of galaxies at an average redshift of one
• Giant Metrewave Radio Telescope Detection of HI 21 cm Emission from Star-forming Galaxies at $z\approx 1.3$
• The Relation between Dynamical Mass-to-Light Ratio and Color for Massive Quiescent Galaxies out to z~2 and Comparison with Stellar Population Synthesis Models
• Towards the first detection of strongly lensed HI emission

Cited by in corpus (4)

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• Neutral hydrogen lensing simulations in the Hubble Frontier Fields
• A search for HI absorption in distant star-forming galaxies with ASKAP-FLASH -- I. Selection and analysis of the radio sample