Chandra Deep Field North 2-Megasecond Catalog

Chandra Deep Field North 2-Megasecond Catalog Chan/DF2N ivo://nasa.heasarc/chandfn2ms NASA/GSFC HEASARC Alexander et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The Chandra Deep Field North (CDFN) 2-Megasecond Catalog contains the point sources found in the ~2 Megasecond (Ms) exposure of the Chandra Deep Field North, currently the deepest X-ray observation of the universe in the 0.5 -8.0 keV band. Five hundred and three (503) X-ray sources were detected over an ~448 square arcminute area in up to seven X-ray bands. Twenty (20) of these X-ray sources lie in the central ~5.3 square arcminute Hubble Deep Field North (13600 (+3800,-3000) sources/deg2). The on-axis sensitivity limits are ~2.5x10-17 ergs/cm2/s (0.5 - 2.0 keV) and 1.4x10-16 ergs/cm2/s (2 - 8 keV). Source positions are determined using matched-filter and centroiding techniques; the median positional uncertainty is ~0.3". The X-ray colors of the detected sources indicate a broad variety of source types, although absorbed AGN (including a small number of possible Compton-thick sources) are clearly the dominant type. The average backgrounds in the 0.5 - 2.0 keV and 2 - 8 keV bands are 0.056 and 0.135 counts Ms-1 pixel-1, respectively. The background count distributions are very similar to Poisson distributions. This 2 Ms exposure is approximately photon limited in all seven X-ray bands for regions close to the aim point. This observation does not suffer from source confusion within ~6 arcminutes of the aim point. This table was created by the HEASARC in April 2004 based on CDS catalog table J/AJ/126/539/cdfn.dat. This is a service provided by NASA HEASARC . 2003AJ....126..539A https://heasarc.gsfc.nasa.gov/W3Browse/all/chandfn2ms.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=chandfn2ms& GET text/xml 180 99999 true 189.27541667 62.02519444 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=chandfn2ms GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_chandfn2ms&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 X-ray public chandfn2ms Chandra Deep Field North 2-Megasecond Catalog name Object Designation meta.id char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable error_radius Position Error (80%-90% Confidence Level) arcsec stat.error;pos float nullable limit_fb_counts Limit Flag on FB_Counts meta.code;phot;em.X-ray char nullable fb_counts 0.5-8.0 keV Band Counts ct phot;em.X-ray double nullable fb_counts_pos_err Upper 1-Sigma Error in FB_Counts ct stat.error;phot;em.X-ray float nullable fb_counts_neg_err Lower 1-Sigma Error in FB_Counts ct stat.error;phot;em.X-ray float nullable sb1_counts_neg_err Lower 1-Sigma Error in SB1_Counts ct stat.error;phot;em.X-ray.soft float nullable limit_photon_index Limit Flag on Sp+Index meta.code;spect.index char nullable limit_ratio_1 Limit Flag on Ratio_1 meta.code;phot.flux;arith.ratio char nullable ratio_4_neg_err Lower 1-Sigma Error in Ratio_4 stat.error;phot.flux;arith.ratio float nullable limit_hb_counts Limit Flag on HB_Counts meta.code;phot;em.X-ray.medium char nullable bii Galactic Latitude degree pos.galactic.lat double nullable limit_fb_flux Limit Flag on FB_Flux meta.code;phot.flux;em.X-ray.medium char nullable sb2_counts 1-2 keV Band Counts ct phot;em.X-ray.soft double nullable source_notes Notes on the Source meta.note;src char nullable flag_hb1_counts Flag on HB1_Counts meta.code;phot;em.X-ray.medium char nullable sb1_flux Flux in the 0.5-1 keV Band (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray double nullable limit_sb1_flux Limit Flag on SB1_Flux meta.code;phot.flux;em.X-ray.soft char nullable hb1_counts_pos_err Upper 1-Sigma Error in HB1_Counts ct stat.error;phot;em.X-ray.medium float nullable hb_counts_neg_err Lower 1-Sigma Error in HB_Counts ct stat.error;phot;em.X-ray.medium float nullable fb_flux Flux in the 0.5-8.0 keV Band (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray double nullable sb2_counts_neg_err Lower 1-Sigma Error in SB2_Counts ct stat.error;phot;em.X-ray.soft float nullable ratio_4_pos_err Upper 1-Sigma Error in Ratio_4 stat.error;phot.flux;arith.ratio float nullable sequence_number Source Number meta.id;meta.main short nullable limit_hb2_counts Limit Flag on HB2_Counts meta.code;phot;em.X-ray.medium char nullable limit_hb_flux Limit Flag on HB_Flux meta.code;phot.flux;em.X-ray.medium char nullable flag_sb_counts Flag on SB_Counts meta.code;phot;em.X-ray.soft char nullable limit_sb_flux Limit Flag on SB_Flux meta.code;phot.flux;em.X-ray.soft char nullable hb1_flux Flux in the 2-4 keV Band (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray.medium double nullable limit_ratio_3 Limit Flag on Ratio_3 meta.code;phot.flux;arith.ratio char nullable flag_photon_index Flag on Sp+Index meta.code.qual;spect.index char nullable limit_sb1_counts Limit Flag on SB1_Counts meta.code;phot;em.X-ray.soft char nullable hb2_counts_neg_err Lower 1-Sigma Error in HB2_Counts ct stat.error;phot;em.X-ray.medium float nullable limit_hb1_flux Limit Flag on HB1_Flux meta.code;phot.flux;em.X-ray.medium char nullable sb_counts 0.5-2 keV Band Counts ct phot;em.X-ray.soft double nullable lii Galactic Longitude degree pos.galactic.lon double nullable sb_counts_pos_err Upper 1-Sigma Error in SB_Counts ct stat.error;phot;em.X-ray.soft float nullable hb1_counts_neg_err Lower 1-Sigma Error in HB1_Counts ct stat.error;phot;em.X-ray.medium float nullable ratio_3_neg_err Lower 1-Sigma Error in Ratio_3 stat.error;phot.flux;arith.ratio float nullable flag_sb2_counts Flag on SB2_Counts meta.code;phot;em.X-ray.soft char nullable ratio_1_pos_err Upper 1-Sigma Error in Ratio_1 stat.error;phot.flux;arith.ratio float nullable limit_ratio_2 Limit Flag on Ratio_2 meta.code;phot.flux;arith.ratio char nullable exposure Effective Exposure (s) s time.duration;obs.exposure double nullable ratio_2_neg_err Lower 1-Sigma Error in Ratio_2 stat.error;phot.flux;arith.ratio float nullable flag_sb1_counts Flag on SB1_Counts meta.code;phot;em.X-ray.soft char nullable sb1_counts 0.5-1 keV Band Counts ct phot;em.X-ray.soft float nullable sb_flux Flux in the 0.5-2 keV Band (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray double nullable sb2_counts_pos_err Upper 1-Sigma Error in SB2_Counts ct stat.error;phot;em.X-ray.soft float nullable hb_flux Flux in the 2-8 keV Band (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray.medium double nullable hb_counts_pos_err Upper 1-Sigma Error in HB_Counts ct stat.error;phot;em.X-ray.medium float nullable ratio_2_pos_err Upper 1-Sigma Error in Ratio_2 stat.error;phot.flux;arith.ratio float nullable limit_ratio_4 Limit Flag on Ratio_4 meta.code;phot.flux;arith.ratio char nullable hb1_counts 2-4 keV Band Counts ct phot;em.X-ray.medium float nullable limit_sb_counts Limit Flag on SB_Counts meta.code;phot;em.X-ray.soft char nullable ratio_4 HB1_Flux/SB2_Flux Count-Rate Ratio phot.flux;arith.ratio;em.X-ray float nullable hb_counts 2-8 keV Band Counts ct phot;em.X-ray.medium float nullable flag_hb2_counts Flag on HB2_Counts meta.code;phot;em.X-ray.medium char nullable hb2_counts 4-8 keV Band Counts ct phot;em.X-ray.medium float nullable limit_hb1_counts Limit Flag on HB1_Counts meta.code;phot;em.X-ray.medium char nullable hb2_flux Flux in the 4-8 keV Band (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray.medium double nullable ratio_3_pos_err Upper 1-Sigma Error in Ratio_3 stat.error;phot.flux;arith.ratio float nullable ratio_3 HB2_Flux/HB1_Flux Count-Rate Ratio phot.flux;arith.ratio float nullable photon_index Power-Law Model Effective Photon Index spect.index float nullable flag_fb_counts Flag on FB_Counts meta.code;phot;em.X-ray char nullable off_axis_angle Off-Axis Angle arcmin instr.offset float nullable limit_hb2_flux Limit Flag on HB2_Flux meta.code;phot.flux;em.X-ray.medium char nullable limit_sb2_flux Limit Flag on SB2_Flux meta.code;phot.flux;em.X-ray.soft char nullable limit_sb2_counts Limit Flag on SB2_Counts meta.code;phot;em.X-ray.soft char nullable sb2_flux Flux in the 1-2 keV Band (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray double nullable hb2_counts_pos_err Upper 1-Sigma Error in HB2_Counts ct stat.error;phot;em.X-ray.medium float nullable ratio_1_neg_err Lower 1-Sigma Error in Ratio_1 stat.error;phot.flux;arith.ratio float nullable sb1_counts_pos_err Upper 1-Sigma Error in SB1_Counts ct stat.error;phot;em.X-ray.soft float nullable ratio_1 HB_Flux/SB_Flux Count-Rate Ratio phot.flux;arith.ratio;em.X-ray float nullable photon_index_neg_err Lower 1-Sigma Error in Sp+Index stat.error;spect.index float nullable photon_index_pos_err Upper 1-Sigma Error in Sp+Index stat.error;spect.index float nullable ratio_2 SB2_Flux/SB1_Flux Count-Rate Ratio phot.flux;arith.ratio float nullable flag_hb_counts Flag on HB_Counts meta.code;phot;em.X-ray.medium char nullable sb_counts_neg_err Lower 1-Sigma Error in SB_Counts ct stat.error;phot;em.X-ray.soft float nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable