James Webb Space Telescope Feed Post

Arxiv: PEARLS: NuSTAR and XMM-Newton Extragalactic Survey of the JWST North Ecliptic Pole Time-Domain Field II Published: 2/21/2024 5:39:51 AM Updated: 4/21/2024 12:09:36 PM

Paper abstract: We present the second NuSTAR and XMM-Newton extragalactic survey of the JWSTNorth Ecliptic Pole (NEP) Time-Domain Field (TDF). The first NuSTAR NEP-TDFsurvey (Zhao et al. 2021) had 681 ks total exposure time executed in NuSTARcycle 5, in 2019 and 2020. This second survey, acquired from 2020 to 2022 incycle 6, adds 880 ks of NuSTAR exposure time. The overall NuSTAR NEP-TDF surveyis the most sensitive NuSTAR extragalactic survey to date, and a total of 60sources were detected above the 95% reliability threshold. We constrain thehard X-ray number counts, logN-log S, down to 1.7 x 10^{-14} erg cm^{-2}s^{-1} at 8-24 keV and detect an excess of hard X-ray sources at the faintend. About 47% of the NuSTAR-detected sources are heavily obscured (NH >10^{23} cm^{-2}), and 18+20% of the NuSTAR-detected sources areCompton-thick (N>10^{24} cm^{-2}). These fractions are consistent withthose measured in other NuSTAR surveys. Four sources presented >2\sigmavariability in the 3-year survey. In addition to NuSTAR, a total of 62 ks ofXMM-Newton observations were taken during NuSTAR cycle 6. The XMM-Newtonobservations provide soft X-ray (0.5-10keV) coverage in the same field andenable more robust identification of the visible and infrared counterparts ofthe NuSTAR-detected sources. A total of 286 soft X-ray sources were detected,out of which 214 XMM-Newton sources have secure counterparts frommultiwavelength catalogs.