Spatially resolved Hα and ionizing photon production efficiency in the lensed galaxy MACS1149-JD1 at a redshift of 9.11

We present MIRI/JWST medium-resolution spectroscopy (MRS) and imaging (MIRIM) of the lensed galaxy MACS1149-JD1 at a redshift of z = 9.1092 +/- 0.0002, when the Universe was about 530 Myr old. We detect, for the first time, spatially resolved H alpha emission in a galaxy at a redshift above nine. The structure of the H alpha emitting gas consists of two clumps, S and N, carrying about 60% and 40% of the total flux, respectively. The total H alpha luminosity implies an instantaneous star-formation rate in the range of 3.2 +/- 0.3 and 5.3 +/- 0.4 M-circle dot yr(-1) for sub-solar and solar metallicities. The ionizing photon production efficiency, log(zeta(ion)), shows a spatially resolved structure with values of 25.55 +/- 0.03; 25.47 +/- 0.03; and 25.91 +/- 0.09 Hz erg(-1) for the integrated galaxy and clumps S and N, respectively. The H alpha rest-frame equivalent width, EW0 (H alpha), is 726( -182)(+660 )& Aring; for the integrated galaxy, but it presents extreme values of 531 -96+300 - 96 + 300(-96)(+300 )& Aring; and >= 1951 & Aring; for clumps S and N, respectively. The spatially resolved ionizing photon production efficiency is within the range of values measured in galaxies at a redshift above six and well above the canonical value (25.2 +/- 0.1 Hz erg(-1)). The EW0 (H alpha) is a factor of two lower than the predicted value at z = 9.11 based on the extrapolation of the evolution of the EW0 (H alpha) with redshifts, proportional to(1 + z)2.1, including galaxies detected with JWST. The extreme difference of the EW0 (H alpha) for clumps S and N indicates the presence of a recent (< 5 Myr) stellar burst in clump N and a star formation over a larger period of time (e.g., similar to 50 Myr) in clump S. The different ages of the stellar population place MACS1149-JD1 and clumps N and S at different locations in the log(zeta(ion)) to EW0 (H alpha) plane and above the main relation defined from intermediate- and high-redshift (z = 3 - 7) galaxies detected with JWST. Finally, clump S and N show very different H alpha kinematics, with velocity dispersions of 56 +/- 4 km s(-1) and 113 +/- 33 km s(-1), likely indicating the presence of outflows or increased turbulence in clump N. The dynamical mass M-dyn = (2.4 +/- 0.5) x 10(9) M-circle dot, obtained from the size of the integrated H alpha ionized nebulae and its velocity dispersion, is within the range previously measured with the spatially resolved [OIII]88 mu m line.