J-Plus: Unveiling The Brightest End Of The Lyff Luminosity Function At 2.0 < Z < 3.3 Over 1000 Deg(2)

We present the photometric determination of the bright end of the Ly alpha luminosity function (LF; at L-Ly alpha greater than or similar to 10(43.3) erg s(-1)) within four redshift windows (Delta z< 0.16) in the interval 2.2 less than or similar to z less than or similar to 3.3. Our work is based on the Javalambre Photometric Local Universe Survey (J-PLUS) first data release, which provides multiple narrow-band measurements over similar to 1000 deg(2), with limiting magnitude r similar to 22. The analysis of high-z Ly alpha-emitting sources over such a wide area is unprecedented and allows us to select approximately 14 500 hyper-bright (L-Ly alpha> 10(43.3) erg s(-1)) Ly alpha-emitting candidates. We test our selection with two spectroscopic programs at the GTC telescope, which confirm similar to 89% of the targets as line-emitting sources, with similar to 64% being genuine z similar to 2.2 quasars (QSOs). We extend the 2.2 less than or similar to z less than or similar to 3.3 Ly alpha LF for the first time above L-Ly alpha similar to 10(44) erg s(-1) and down to densities of similar to 10(-8) Mpc(-3). Our results unveil the Schechter exponential decay of the brightest-end of the Ly alpha LF in great detail, complementing the power-law component of previous determinations at 43.3 less than or similar to Log(10)(L-Ly alpha/erg s(-1)) less than or similar to 44. We measure Phi(*)=(3.33 +/- 0.19)x10(-6), Log(L-*) = 44.65 +/- 0.65, and alpha=-1.35 +/- 0.84 as an average over the probed redshifts. These values are significantly different from the typical Schechter parameters measured for the Ly alpha LF of high-z star-forming Lyman-alpha emitters (LAEs). This implies that z> 2 AGNs/QSOs (likely dominant in our samples) are described by a structurally different LF from that used to describe z > 2 star-forming LAEs, namely L-QSOs(*) similar to 100L(LAEs)(*), with the transition between the two LFs happening at L-Ly alpha similar to 10(43.5) erg s(-1). This supports the scenario in which Ly alpha-emitting AGNs/QSOs are the most abundant class of z greater than or similar to 2 Ly alpha emitters at L-Ly alpha greater than or similar to 10(43.3) erg s(-1). Finally, we suggest that a significant number of these z greater than or similar to 2 AGNs/QSOs (similar to 60% of our samples) are currently misclassified as stars based on their broad-band colours, but are identified for the first time as high-z line-emitters by our narrow-band-based selection.