We consider a forming galaxy undergoing multitudinous supernova ( SN ) explosions , as a possible model of Ly \alpha blobs ( LABs ) .
For this purpose , an ultra–high resolution hydrodynamic simulation is performed using 1024 ^ { 3 } grid points , where SN remnants are resolved with sufficient accuracy .
It is found that multiple SN explosions produce kpc–size expanding hot bubbles , which drive cool , dense shells by strong shock .
The colliding high–density cooling shells radiate intensive Ly \alpha emission , resulting in a high Ly \alpha luminosity of \sim 10 ^ { 43 } erg s ^ { -1 } , comparable to the observed level in LABs .
Also , recently discovered bubbly features in some LABs are quite similar to the structure predicted in the present simulation .
Furthermore , the result demonstrates that LABs are representative of evolving primordial galaxies ; they could hold direct information on the early chemical enrichment of galaxies , contrary to present–day galaxies which have undergone intense recycling of interstellar matter , thus erasing most of the early chemical history .
It turns out that the metal mixing proceeds in a very inhomogeneous fashion , so that there appears a large spread of metallicity , that is , [ { Fe / H } ] \approx 0 { ~ { } to } -5 or [ { O / H } ] \approx 1 { ~ { } to } -4 .
Hence , the early galactic chemical evolution may have proceeded in a different manner from that hitherto considered in one–zone models .