releases early_data_release

J-PLUS Early Data Release

J-PLUS Early Data Release (EDR) comprises 18 J-PLUS fields observed with 12 optical bands amounting to 36deg2 (31.7deg2 after masking), with 150k stars and 101k galaxies at r < 21.

The main characteristics of the J-PLUS filter system, EDR limiting magnitudes and median zero points are summarized in the following table:

# Filter Filter name CW (Å) FWHM (Å) m_lim EDR ZP
1 u 3485 508 21.6 21.1
2 J0378 3785 168 21.5 20.5
3 J0395 3950 100 21.4 20.3
4 J0410 4100 200 21.5 21.3
5 J0430 4300 200 21.5 21.4
6 g 4803 1409 22.2 23.6
7 J0515 5150 200 21.4 21.5
8 r 6254 1388 21.9 23.6
9 J0660 6600 145 21.3 21.0
10 i 7668 1535 20.8 23.3
11 J0861 8610 400 20.8 21.5
12 z 9114 1409 20.5 22.6

Scope

Total area covered 36deg2 (31.7deg2 after masking)
Image field size 9500x9500 pixels (2 square degrees)
Image pixel scale 0.555 arcsec
Number total of fields 18
Number of objects in dual catalogue 413.869
Number of objects in single catalogue 3.072.287

Science Pieces

A colour image of the J-PLUS field 01488 is presented in figure 1. A great variety of astronomical sources are placed in the 2 deg2 FoV of T80Cam@JAST/T80: main sequence stars, white dwarfs (WD), galaxies, distant QSOs, minor bodies (MB) of the Solar System, etc. In figure 2 a collection of J-PLUS photo-spectra with 12 bands is presented, including the spectroscopic counterpart from SDSS.
Colour image of the J-PLUS  field 01488

Figure 1. Colour image of the J-PLUS field 01488.

J-PLUS photo-spectra with 12 bands of the sources marked in figure 1

Figure 2. J-PLUS photo-spectra with 12 bands of the sources marked in figure 1

Data summary

The sky coverage of the J-PLUS EDR is shown as black in figure 3. Bright stars are masked (white areas) to ensure high quality photometry, with 31.7 deg2 and 251k sources at r < 21.
Sky coverage of the J-PLUS EDR

Figure 3. Sky coverage of the J-PLUS EDR

The EDR limiting magnitude distribution is presented in figure 4, where we indicate the target J-PLUS limits by means of a vertical line, the general distribution of the gathered J-PLUS data (grey histogram) and the distribution of the J-PLUS EDR (coloured histograms). We can appreciate that, with the exception of the i filter, the EDR is fairly close to the target J-PLUS magnitudes.
EDR limiting magnitude distribution

Figure 4. EDR limiting magnitude distribution

The FWHM and ellipticity distributions of the J-PLUS EDR are shown bellow in figure 5. The values are consistent with those of the parent J-PLUS data, and show FWHM <1.5''. The completeness for stars (point-like sources) and galaxies (extended sources) was computed by comparing with the SDSS dataset in the common areas. The median 50% completeness in J-PLUS EDR tiles is r=21.51 for stars and r=21.10 for galaxies. For reference, the median 95% completeness is reached at r=20.88 for stars and r=20.12 for galaxies.
FWHM and ellipticity distributions of the J-PLUS EDR

Figure 5. EDR limiting magnitude distribution

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