TY - JOUR
T1 - DESI DR2 Galaxy luminosity functions
AU - DESI Collaboration
AU - Moore, Samuel G.
AU - Cole, Shaun
AU - Norberg, Peder
AU - Moustakas, John
AU - Aguilar, J.
AU - Ahlen, S.
AU - Anand, A.
AU - Bianchi, D.
AU - Brooks, D.
AU - Castander, F. J.
AU - Claybaugh, T.
AU - Cuceu, A.
AU - Macorra, A. de la
AU - Dey, Arjun
AU - Dey, Biprateep
AU - Ferraro, S.
AU - Font-Ribera, A.
AU - Forero-Romero, J. E.
AU - Gaztanaga, E.
AU - Gontcho, S. Gontcho A
AU - Gutierrez, G.
AU - Herrera-Alcantar, H. K.
AU - Honscheid, K.
AU - Ishak, M.
AU - Joyce, R.
AU - Juneau, S.
AU - Kehoe, R.
AU - Kisner, T.
AU - Koposov, S. E.
AU - Kremin, A.
AU - Lahav, O.
AU - Lamman, C.
AU - Landriau, M.
AU - Guillou, L. Le
AU - Levi, M. E.
AU - Manera, M.
AU - Meisner, A.
AU - Miquel, R.
AU - Nadathur, S.
AU - Percival, W. J.
AU - Poppett, C.
AU - Prada, F.
AU - Ross, A. J.
AU - Rossi, G.
AU - Sanchez, E.
AU - Schlegel, D.
AU - Schubnell, M.
AU - Seo, H.
AU - Silber, J.
AU - Sprayberry, D.
N1 - 19 pages, 19 figures
PY - 2026/6/1
Y1 - 2026/6/1
N2 - We present luminosity functions (LFs) in the g, r, z, and W_1 bands from the DESI Year 3 Bright Galaxy Survey (BGS), spanning redshifts 0.002 -15, stronger in red galaxies. Below -13, local overdensities and fragmentation of large galaxies amplify this upturn. A systematic offset between North and South appears at the brightest magnitudes, driven by red galaxies. Blue LFs match well across regions, suggesting the discrepancy arises from red galaxy profiles blending into noise in shallower North photometry. This remains inconclusive, so the bright-end offset is treated as a systematic uncertainty. We also present LFs using model Petrosian magnitudes, which are less sensitive to this issue. Splitting by redshift reveals small but significant residuals, indicating our global evolution model, while accurate near the LF knee, misses more complex trends. Using Loveday (2011) redshift limits, we find excellent agreement with GAMA, but with smaller errors. Our methods and results provide a foundation for studying LF dependence on environment, such as local density and cosmic web classification, offering strong constraints on galaxy formation models.
AB - We present luminosity functions (LFs) in the g, r, z, and W_1 bands from the DESI Year 3 Bright Galaxy Survey (BGS), spanning redshifts 0.002 -15, stronger in red galaxies. Below -13, local overdensities and fragmentation of large galaxies amplify this upturn. A systematic offset between North and South appears at the brightest magnitudes, driven by red galaxies. Blue LFs match well across regions, suggesting the discrepancy arises from red galaxy profiles blending into noise in shallower North photometry. This remains inconclusive, so the bright-end offset is treated as a systematic uncertainty. We also present LFs using model Petrosian magnitudes, which are less sensitive to this issue. Splitting by redshift reveals small but significant residuals, indicating our global evolution model, while accurate near the LF knee, misses more complex trends. Using Loveday (2011) redshift limits, we find excellent agreement with GAMA, but with smaller errors. Our methods and results provide a foundation for studying LF dependence on environment, such as local density and cosmic web classification, offering strong constraints on galaxy formation models.
KW - astro-ph.GA
KW - galaxies: luminosity function
KW - mass function –galaxies: statistics
U2 - 10.1093/mnras/stag866
DO - 10.1093/mnras/stag866
M3 - Article
SN - 0035-8711
VL - 549
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 2
M1 - stag866
ER -