IC2944XMM ivo://nasa.heasarc/ic2944xmm NASA/GSFC HEASARC Naze et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source Using XMM-Newton data, the authors have studied for the first time the X-ray emission of the young star clusters HM1 and IC 2944/2948. Low-mass, pre-main sequence objects with an age of a few Myr are detected, as well as a few background or foreground objects. Most massive stars in both clusters display the usual high-energy properties of that kind of objects, though with log(L<sub>x</sub>/L<sub>bol</sub>) apparently lower in HM1 than in IC 2944/2948. Comparing with studies of other clusters, it seems that low S/N at soft energies, due to the high extinction, may the main cause of this difference. In HM1, the two Wolf-Rayet stars show contrasting behaviors: WR89 is extremely bright, but much softer than WR87. It remains to be seen whether wind-wind collisions or magnetically confined winds can explain such emissions. In IC 2944/2948, the X-ray sources concentrate around HD 101205; a group of massive stars to the north of this object appears rather isolated, suggesting that there exist two sub-clusters in the field of view. This tables provides the list of 368 detected X-ray sources in/toward the Cen OB2 association cluster(s) IC 2944/2948 only, i.e., the 58 X-ray sources detected in/toward the HM1 cluster are not contained herein. This tables lists the basic X-ray source properties (position, count rates, hardness ratios) and their probable optical/infrared counterparts (offset angular distance, name). XMM-Newton has observed IC 2944/2948 for 40 ks on XMM-Newton Rev. 2209 (with the THICK filter). No background flare affected the observation, and no source is bright enough to suffer from pile-up. This table was created by the HEASARC in September 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/555/A83">CDS Catalog J/A+A/555/A83</a> files table3.dat and table4.dat. This is a service provided by NASA HEASARC . 2013A&A...555A..83N https://heasarc.gsfc.nasa.gov/W3Browse/all/ic2944xmm.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=ic2944xmm& GET text/xml 180 99999 true 174.62299583 -63.59736389 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=ic2944xmm GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_ic2944xmm&Action=More+Options&Action=Parameter+Search&ConeAdd=1 XMM-NEWTON 0.0166666666666667 X-ray public ic2944xmm IC 2944/2948 XMM-Newton X-Ray Source Catalog source_number Sequential Identification Number for Each Source in Catalog meta.id;src short nullable name Source Designation meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable pn_count_rate Count Rate for pn ct/s phot.count;em.X-ray double nullable pn_count_rate_error Error in pn Count Rate ct/s stat.error;phot.count;em.X-ray double nullable twomass_name Designation of 2MASS Counterpart meta.id.cross char nullable xmm_2mass_offset Distance from 2MASS Counterpart arcsec pos.angDistance;em.X-ray;em.IR double 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 hardness_ratio_2_error Error in Hardness Ratio 2 for pn stat.error;phot.flux;arith.ratio;em.X-ray double nullable raw_ra Raw (Uncorrected) Right Ascension degree pos.eq.ra double nullable bii Galactic Latitude degree pos.galactic.lat double nullable lii Galactic Longitude degree pos.galactic.lon double nullable xmm_mgcat_offset Distance from MG Counterpart arcsec pos.angDistance;em.X-ray;em.opt double nullable ctrpart_flag Flag [+] Indicates Presence of a Second 2MASS Counterpart Farther Away meta.code;src char nullable m2_count_rate Count Rate for MOS2 ct/s phot.count;em.X-ray double nullable xmm_simbad_offset Distance from SIMBAD Counterpart arcsec pos.angDistance double nullable simbad_name Name of SIMBAD Counterpart meta.id.cross char nullable h_alpha_ew Equivalent Width of H-Alpha in the MG Catalog Counterpart Angstrom spect.line.eqWidth;em.line.Halpha double nullable hardness_ratio_1_error Error in Hardness Ratio 1 for pn stat.error;phot.flux;arith.ratio;em.X-ray double nullable m2_count_rate_error Error in MOS2 Count Rate ct/s stat.error;phot.count;em.X-ray double nullable m1_count_rate Count Rate for MOS1 ct/s phot.count;em.X-ray double nullable hardness_ratio_2 Hardness Ratio 2 for pn phot.flux;arith.ratio;em.X-ray double nullable comments Additional Information (Spectral Type, Period...) meta.note char nullable raw_dec Raw (Uncorrected) Declination degree pos.eq.dec double nullable source_flag Flag Indicates the Following: ?=Probably Spurious Source; ext=Extended Source meta.code;src char nullable m1_count_rate_error Error in MOS1 Count Rate ct/s stat.error;phot.count;em.X-ray double nullable hardness_ratio_1 Hardness Ratio 1 for pn phot.flux;arith.ratio;em.X-ray double nullable mgcat_name Designation in MG Catalog meta.id.cross char nullable