PEARLS: NuSTAR and XMM-Newton Extragalactic Survey of the JWST North Ecliptic Pole Time-domain Field III

Abstract

The James Webb Space Telescope (JWST) North Ecliptic Pole (NEP) Time-Domain Field (TDF) has been monitored by NuSTAR and XMM-Newton with a regular cadence for five years starting in 2019. The survey has accumulated 3.5Ms of NuSTAR exposure and 228 ks quasi-simultaneous XMM-Newton observations covering 0.31 deg². This paper presents the results from the most recent two-years' 2Ms NuSTAR and 166 ks XMM observations in NuSTAR cycles 8 and 9. These observations reached a 20%-area flux of 2.20 x 10⁻¹⁴ erg cm⁻² s⁻¹ in the 8-24 keV band. 75 NuSTAR sources and 274 XMM-Newton sources are detected at 99% reliability level. The logN-logS measured in cycles 8+9 are consistent with those measured in the previous cycle 5+6 NuSTAR NEP survey, but in a larger area (0.3 deg² compared with 0.19 deg²). The slope of the cycles 8+9 8-24 keV logN-logS curve is flatter than other works (α₈₉ = 1.13 +/- 0.46), but is consistent with the Euclidean value of α = 1.50. In addition, we found ~36% of the NuSTAR sources to be heavily obscured (N_H >= 10²³cm⁻²). The Compton-thick (N_H >= 10²⁴ cm⁻²) (CT-) AGN fraction is 9⁺¹⁸₋₈% in the NEP-TDF, which is consistent with the measurements in previous surveys.  : subscript