High-redshift, Small-scale Tests of Ultralight Axion Dark Matter Using Hubble and Webb Galaxy UV Luminosities

TY - JOUR

T1 - High-redshift, Small-scale Tests of Ultralight Axion Dark Matter Using Hubble and Webb Galaxy UV Luminosities

AU - Winch, Harrison

AU - Rogers, Keir K.

AU - Hložek, Renée

AU - Marsh, David J. E.

PY - 2024/11/12

Y1 - 2024/11/12

N2 - We calculate the abundance of UV-bright galaxies in the presence of ultralight axion (ULA) dark matter (DM), finding that axions suppress their formation with a non-trivial dependence on redshift and luminosity. We set limits on axion DM using UV luminosity function (UVLF) data, excluding a single axion as all the DM for max < 10−21.6 eV and limiting axions with -26 log eV 2   ( ) max - 3 to be less than 22% of the DM (both at95% credibility). These limits use UVLF measurements from 24,000 sources from the Hubble Space Telescope(HST) at redshifts 4 „ z „ 10. We marginalize over a parametric model connecting halo mass and UV luminosity.Our results bridge a window in axion mass and fraction previously unconstrained by cosmological data, betweenlarge-scale cosmic microwave background and galaxy clustering and the small-scale Lyα forest. These high-zmeasurements provide a powerful consistency check of low-z tests of axion DM, including the recent hint for asub-dominant ULA DM fraction in Lyα forest data. We also consider a sample of 25 spectroscopically confirmedhigh-z galaxies from the James Webb Space Telescope (JWST), finding these data to be consistent with HST.Combining HST and JWST UVLF data does not improve our constraints beyond HST alone, but future JWSTmeasurements have the potential to improve these results. We also find an excess of low-mass halos (<109Me) at z < 3, which could be probed by subgalactic structure probes (e.g., stellar streams, satellite galaxies, and stronglensing).

AB - We calculate the abundance of UV-bright galaxies in the presence of ultralight axion (ULA) dark matter (DM), finding that axions suppress their formation with a non-trivial dependence on redshift and luminosity. We set limits on axion DM using UV luminosity function (UVLF) data, excluding a single axion as all the DM for max < 10−21.6 eV and limiting axions with -26 log eV 2   ( ) max - 3 to be less than 22% of the DM (both at95% credibility). These limits use UVLF measurements from 24,000 sources from the Hubble Space Telescope(HST) at redshifts 4 „ z „ 10. We marginalize over a parametric model connecting halo mass and UV luminosity.Our results bridge a window in axion mass and fraction previously unconstrained by cosmological data, betweenlarge-scale cosmic microwave background and galaxy clustering and the small-scale Lyα forest. These high-zmeasurements provide a powerful consistency check of low-z tests of axion DM, including the recent hint for asub-dominant ULA DM fraction in Lyα forest data. We also consider a sample of 25 spectroscopically confirmedhigh-z galaxies from the James Webb Space Telescope (JWST), finding these data to be consistent with HST.Combining HST and JWST UVLF data does not improve our constraints beyond HST alone, but future JWSTmeasurements have the potential to improve these results. We also find an excess of low-mass halos (<109Me) at z < 3, which could be probed by subgalactic structure probes (e.g., stellar streams, satellite galaxies, and stronglensing).

U2 - 10.3847/1538-4357/ad7a73

DO - 10.3847/1538-4357/ad7a73

M3 - Article

SN - 0004-637X

VL - 976

JO - ASTROPHYSICAL JOURNAL

JF - ASTROPHYSICAL JOURNAL

IS - 1

M1 - 40

ER -