Superwind Model of Extended Lyalpha Emitters at High Redshift

Area of Science:

• Cosmic structure formation
• Galaxy evolution
• High-redshift astronomy

Background:

• Extended Lyalpha blobs (LABs) are luminous, large-scale emission nebulae observed at high redshifts (z ~ 3).
• Their formation mechanisms and connection to host galaxies remain poorly understood.
• Previous observations highlight their high luminosity, elongated morphology, large physical sizes (~100 kpc), broad line widths (~1000 km/s), and lack of association with strong radio sources.

Purpose of the Study:

• To propose and validate a new theoretical model for the origin of extended Lyalpha blobs.
• To explain the observed properties of LABs using a unified framework.
• To connect the observed population of LABs to their potential present-day counterparts.

Main Methods:

• Development of a theoretical model based on galactic winds.
• Simulation of winds driven by successive supernova explosions following intense star formation.
• Comparison of model predictions with observational properties of high-redshift LABs.
• Estimation of the number density of LABs and their potential evolved galaxy populations.

Main Results:

• The proposed model successfully explains the key observational properties of extended Lyalpha blobs, including their luminosity, size, morphology, and line width.
• Galactic winds, powered by supernova explosions in the aftermath of massive starbursts, are identified as the likely driving mechanism.
• The observed number density of LABs is consistent with a population of massive elliptical galaxies at the present epoch (luminosity > 1L*).

Conclusions:

• Galactic winds provide a viable explanation for the existence and properties of extended Lyalpha blobs at high redshift.
• LABs represent an important phase in the evolution of massive galaxies, likely progenitors of present-day massive elliptical galaxies.
• Further observational and theoretical studies are needed to refine the understanding of these early cosmic structures.