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eROSITA-DE DR1 Main

The eROSITA telescope array aboard the Spektrum Roentgen Gamma (SRG) satellite began surveying the sky in December 2019. Data Release 1 (DR1) presents X-ray catalogues, calibrated event files, source products, and all-sky maps from the first eROSITA All-Sky Survey (eRASS1), which spanned six months of operations from December 2019 to June 2020. This release comprises data covering the western Galactic hemisphere, the half-sky proprietary to the German eROSITA Consortium (eROSITA-DE).

The DR1 data is organized into 2447 sky tiles and provides source catalogues in two primary X-ray bands: a main catalogue from the most sensitive 0.2–2.3 keV energy range, and a hard catalogue from the 2.3–5.0 keV band.

The resultant eRASS1 main catalogue (0.2–2.3 keV) contains 930,203 entries (903,521 point-like and 26,682 extended sources) selected with a detection likelihood DET_LIKE_0 ≥ 6 (or EXT_LIKE > 0). A smaller catalogue of 5,466 sources is presented from the hard (2.3–5.0 keV) band, selected with DET_LIKE_3 ≥ 12. This eRASS1 main catalogue increases the number of known X-ray sources in the published literature by more than 60%.

Key performance metrics and survey characteristics include:

  • Median Survey PSF HEW (0.2–2.3 keV): 30.0"
  • Median Survey PSF HEW (2.3–5.0 keV): 34.4"
  • Flux Limit (0.5–2 keV, 50% completeness): F(0.5–2 keV) > 5 × 10⁻¹⁴ erg s⁻¹ cm⁻²
  • Absolute Flux Accuracy (0.5–2 keV): ~6% systematic uncertainty (relative to XMM-Newton)
  • Astrometric Systematic Uncertainty: σ₀ = 0.9" ± 0.1" (based on Gaia/unWISE QSO cross-matching)
  • Spurious Source Fraction (Main Cat.): ~14% (for DET_LIKE_0 ≥ 6)
  • Spurious Source Fraction (Hard Cat.): ~8–10% (for DET_LIKE_3 ≥ 12)
  • Resolved CXB Fraction (1–2 keV): ~19% (median value at the uniform flux limit)
eROSITA-DE DR1 Main Angular Density Map
Source image: https://data.lsdb.io

Load using LSDB

>>> lsdb.open_catalog('https://linea.data.lsdb.io/hats/erosita')

Download with wget

$ wget -e robots=off -r -np -nH --cut-dirs=1 -c -R "index.html*" -l 0 https://linea.data.lsdb.io/hats/erosita/

Catalog metadata

Number of rows Number of columns Number of partitions Size on disk
930,203 255 10 994 MB