Deep Hubble Space Telescope Imaging on the Extended Ly$\alpha$ Emission of a QSO at $z=2.19$ with Damped Lyman Alpha System as a Natural Coronagraph

Abstract

Recent observations suggest that proximate damped Ly$\alpha$ (PDLA) systems can be used to study the host galaxies of Quasi-stellar objects (QSOs), because the PDLAs can block the bright point-spread-function (PSF) from central QSOs. Using six-orbits of narrowband imaging with $HST$/WFC3, we present the first high resolution narrowband image of the Ly$\alpha$ emission in the PDLA trough of the QSO SDSSJ115432.67-021537.9 . We detect one major component and one minor component in the narrowband imaging. Combining the $HST$/WFC3 imaging with deep Magellan/MagE spectra, we measure that the Ly$\alpha$ flux F${}_{\mathrm{Ly}\alpha }$ = 1.56$\pm 0.10\times 10^{-16}$ $\mathrm{erg}{\mathrm{s}}^{-1}\mathrm{c}{\mathrm{m}}^{-2}$, which is among the luminous ($\approx$ 2.7 L${}_{\mathrm{Ly}\alpha }^{\star }$) Ly$\alpha$ emitters at $z=$ 2.19. The $\mathrm{Ly}\alpha$-based star formation rate (SFR) is $\sim$ 7 $\textrm{M_{\sun} \ yr^{-1}}$. These observational results favor that the star formation from the host galaxy could be the main mechanism to power the Ly$\alpha$ emission. This new method sheds new light on the study of the kinematic structure and the spatial distribution of the extended Ly$\alpha$ emitting regions around the QSO host.

References in corpus (5)

• The Subaru/XMM-Newton Deep Survey (SXDS). IV. Evolution of Lya Emitters from z=3.1 to 5.7 in the 1 deg^2 Field: Luminosity Functions and AGN
• A z = 3 Lyman Alpha Blob Associated with a Damped Lyman Alpha System Proximate to its Background Quasar
• Host galaxies of bright high redshift quasars: Luminosities and colours
• A Glimpse at Quasar Host Galaxy Far-UV Emission, Using DLAs as Natural Coronagraphs
• Constraining Very High Mass Population III Stars through He II Emission in Galaxy BDF-521 at z = 7.01

Cited by in corpus (2)

• J1721$+$8842: a gravitationally lensed binary quasar with a proximate damped Lyman-$\alpha$ absorber
• Deep Learning Prediction of Quasars Broad Ly$\alpha$ Emission Line