As the most extreme members of the rapidly evolving faint blue galaxy population at intermediate redshift , the compact narrow emission line galaxies ( CNELGs ) are intrinsically luminous ( -22 \lesssim { M _ { B } } \lesssim - 18 ) with narrow emission linewidths ( 30 \lesssim \sigma \lesssim 125 km s ^ { -1 } ) .
Their nature is heavily debated : they may be low-mass starbursting galaxies that will fade to present-day dwarf galaxies or bursts of star formation temporarily dominating the flux of more massive galaxies , possibly related to in situ bulge formation or the formation of cores of galaxies .
We present deep , high-quality ( \sim 0 \farcs 6 - 0 \farcs 8 ) images with CFHT of 27 CNELGs .
One galaxy shows clear evidence for a tidal tail ; the others are not unambiguously embedded in galactic disks .
Approximately 55 % of the CNELGS have sizes consistent with local dwarfs of small-to-intermediate sizes , while 45 % have sizes consistent with large dwarfs or disks galaxies .
At least 4 CNELGs can not harbor substantial underlying disk material ; they are low-luminosity galaxies at the present epoch ( M _ { B } > -18 ) .
Conversely , 15 are not blue enough to fade to low-luminosity dwarfs ( { M _ { B } } > -15.2 ) .
The majority of the CNELGs are consistent with progenitors of intermediate-luminosity dwarfs and low-luminosity spiral galaxies with small disks .
CNELGs are a heterogeneous progenitor population with significant fractions ( up to 44 % ) capable of fading into today ’ s faint dwarfs ( { M _ { B } } > -15.2 ) , while 15 to 85 % may only experience an apparently extremely compact CNELG phase at intermediate redshift but remain more luminous galaxies at the present epoch .