J-PLUS: Spectroscopic validation of H$α$ emission line maps in spatially resolved galaxies

TL;DR

The paper validates spatially resolved H$\alpha$+[NII] maps derived from J-PLUS DR3 by cross-matching with IFU data from PHANGS-MUSE, CALIFA, and MaNGA. It introduces the J-SHE pipeline, comprising J-IFU, IFU, and Analysis modules, to produce emaps, perform PSF homogenization, apply zero-point corrections, and extract radial profiles and clump SEDs via a three-filter continuum subtraction approach. Cross-instrument comparisons show good agreement in H$\alpha$ maps, radial profiles, and emission-line region SEDs, with J-PLUS recovering H$\alpha$ flux to within about 2% bias and 7% dispersion after accounting for continuum and PSF effects. The results demonstrate that J-PLUS provides reliable, wide-field, spatially resolved emission maps suitable for statistical studies of star formation in nearby galaxies and pave the way for J-PAS to map resolved galaxy properties over thousands of square degrees.

Abstract

We present a dedicated automated pipeline to construct spatially resolved emission H$α$+[NII] maps and to derive the spectral energy distributions (SEDs) in 12 optical filters (five broad and seven narrow/medium) of H$α$ emission line regions in nearby galaxies (z $<$ 0.0165) observed by the Javalambre Photometric Local Universe Survey (J-PLUS). We used the $J0660$ filter of $140$Å width centered at $6600$Å to trace H$α$ + [NII] emission and $r$ and $i$ broad bands were used to estimate the stellar continuum. We create pure emission line images after the continnum subtraction, where the H$α$ emission line regions were detected. This method was also applied to Integral Field Unit (IFU) spectroscopic data from PHANGS-MUSE, CALIFA and MaNGA surveys by building synthetic narrow-bands based on J-PLUS filters. The studied sample includes the cross-matched catalog of these IFU surveys with J-PLUS third data release (DR3), amounting to $2$ PHANGS-MUSE, $78$ CALIFA, and $78$ MaNGA galaxies at $z < 0.0165$, respectively. We compared the H$α$+[NII] radial profiles from J-PLUS and the IFU surveys, finding good agreement within the expected uncertainties. We also compared the SEDs from the emission line regions detected in J-PLUS images, reproducing the main spectral features present in the spectroscopic data. Finally, we compared the emission fluxes from the J-PLUS and IFU surveys accounting for scale differences, finding a difference of only 2% with a dispersion of 7% in the measurements. The J-PLUS data provides reliable spatially resolved H$α$+[NII] emission maps for nearby galaxies. We provide the J-PLUS DR3 catalog for the $158$ galaxies with IFU data, including emission maps, SEDs of star-forming clumps, and radial profiles.

Figures (17)

• Figure 1: Comparison of J-PLUS FoV for a single pointing with other IFUs. Left panel: The full FoV of J-PLUS (pointing 02433 including M101). Right panel: 10$^{\prime}$$\times$ 10$^{\prime}$ field of J-PLUS observation of M101 and the FoVs of MUSE in its wide-field mode (59.9$^{\prime\prime}$$\times$ 60$^{\prime\prime}$), and narrow-field mode(7.42$^{\prime\prime}$$\times$ 7.43$^{\prime\prime}$), CALIFA (78$^{\prime\prime}$) and MaNGA (32$^{\prime\prime}$) are marked.
• Figure 2: The Filter curves of J-PLUS compared to the spectra of PHANGS-MUSE (NGC1087 at 307, 457 xy position), CALIFA (NGC3395 spectra at 79, 72 xy position), and MaNGA (MaNGA--8150-6103 spectra at 26, 27 xy position).
• Figure 3: Coverage of J-PLUS DR3 overplotted with the distribution of cross matched catalogs of J-PLUS DR3 with PHANGS-MUSE, CALIFA, and MaNGA.
• Figure 4: Flowchart of the J-SHE modules. Top left: J-IFU module. Top right: IFU module. Bottom: Analysis module. White ellipses are inputs, purple blocks are external packages, blue boxes indicate different processes, and green hexagons represent outputs.
• Figure 5: H$\alpha$+[NII] emap of NGC 1087 in J-PLUS and in PHANGS-MUSE (2x3 MUSE pointings) constructed in Sect. \ref{['sec:jifumodule']} and Sect. \ref{['sec:ifumodule']}. The J-PLUS images in 12 filters are shown in the top panel, plotted with the same surface brightness level.