J/ApJ/936/72ivo://CDS.VizieR/J/ApJ/936/72doi:10.26093/cds/vizier.19360072CDSBluem J.Kaaret P.Kuntz K.D.Jahoda K.Koutroumpa D.Hodges-Kluck E.,Fuller C.A.LaRocca D.M.Zajczyk A.2022-09-14T05:57:01Z2022-09-06T12:42:42ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frmilky-way-galaxyx-ray-sourcesinterstellar-mediumsurveysSurrounding the Milky Way (MW) is the circumgalactic medium (CGM), an extended reservoir of hot gas that has significant implications for the evolution of the MW. We used the HaloSat all-sky survey to study the CGM's soft X-ray emission in order to better define its distribution and structure. We extend a previous HaloSat study of the southern CGM (Galactic latitude b<-30{deg}) to include the northern CGM (b>30{deg}) and find evidence that at least two hot gas model components at different temperatures are required to produce the observed emission. The cooler component has a typical temperature of kT~0.18keV, while the hotter component has a typical temperature of kT~0.7keV. The emission measure in both the warm and hot components has a wide range ~0.005-0.03, ~0.0005-0.004cm^-6^*pc respectively), indicating that the CGM is clumpy. A patch of relatively consistent CGM was found in the north, allowing for the CGM spectrum to be studied in finer detail using a stacked spectrum. The stacked spectrum is well described with a model including two hot gas components at temperatures of kT=0.166+/-0.005keV and kT=0.69^+0.04^_-0.05_keV. As an alternative to adding a hot component, a neon-enhanced single-temperature model of the CGM was also tested and found to have worse fit statistics and poor residuals.2022ApJ...936...72Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/936/72CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/936/72https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/936/72http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/936/72https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/936/72https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/936/72http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/936/72GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/936/72/cgmcat (Observation details and spectral fit results)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/936/72/cgmcat?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/936/72/cgmcat?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/936/72/cgmcat?GETtext/xml+votable180.050000true251.011.999830.0055555555555555566/134 388 609 2102 4319 4474 4938 5024 5242 5558 5650 5754 5795 5969 6073 6451 6614 7268 7416 7575 7986 8023 8319 8351 8468 8674 8790 8808 8842 9121 9267 9593 9656 9739 9838 10269 10366 10567 10745 10790 10932 11008 11156 11245 11290 11842 11975 13328 16511 16708 16831 16960 17122 17293 17450 17528 17896 17990 18055 18167 18390 18478 18726 18771 18971 19135 19202 19320 19373 19567 19620 19812 19903 20047 21152 22709 23042 23208 23436 24808 24876 25223 25333 25369 25567 25699 25771 25947 26029 26310 26461 26519 26687 26937 27231 27279 27391 27479 27593 27706 28055 28264 28345 28426 28640 31366 31484 31527 31610 32456 32702 33462 33760 34159 34322 34495 34560 34646 34713 35009 35065 35264 35463 35570 35636 36034 36201 36363 36557 36630 36799 40447 43865 44271 44694 44852 44969 45168 45403 45451 45936 45955 46167 46221 46480 46557 46740 46842 46862 46969 47397 47478 48373 48415 48646 48969https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/936/72?format=asciiX-raydefaultJ/ApJ/936/72/cgmcatObservation details and spectral fit resultsE_EMHEM of hot component upper error (90% CI) (EM_H_err_U)pc.cm**-6stat.error;stat.maxdoubleGLONGalctic longitude (GLON)degpos.galactic.lona561SWCX gauss norm at 0.561 keV (a561)ph.cm**-2.s**-1phot.flux.density;em.gamma.hardfloata654SWCX gauss norm at 0.654 keV (a654)ph.cm**-2.s**-1phot.flux.density;em.gamma.harddouble_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decnullableindexedIDHaloSat field ID, hsNNNN (ID)meta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGLATGalctic latitude (GLAT)degpos.galactic.latExpTimeExposure time (EXPOS)stime.duration;obs.exposureintChi2Reduced chi^2^ of fit (CHI)stat.fit.chi2floatEMWEmission measure of warm component (EM_W)pc.cm**-6phys.emissMeasuredoubleE_EMWEM of warm component upper error (90% CI) (EM_W_err_U)pc.cm**-6stat.error;stat.maxdoublee_EMWEM of warm component lower error (90% CI) (EM_W_err_L)pc.cm**-6stat.errordoublekTWTemperature of warm component (kT_W)keVphys.temperaturefloatE_kTWWarm temperature upper error (90% CI) (kT_W_err_U)keVstat.error;stat.maxfloate_kTWWarm temperature lower error (90% CI) (kT_W_err_L)keVstat.errorfloatEMHEmission measure of hot component (EM_H)pc.cm**-6phys.emissMeasuredoublee_EMHEM of hot component lower error (90% CI) (EM_H_err_L)pc.cm**-6stat.errordoublekTHTemperature of hot component (kT_H) (1)keVphys.temperaturefloatE_kTHHot temperature upper error (90% CI) (kT_H_err_U) (1)keVstat.error;stat.maxfloate_kTHHot temperature lower error (90% CI) (kT_H_err_L) (1)keVstat.errorfloatOVIIWOVII line strength of warm component (OVII_W) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_OVIIWOVII strength of warm component error (90% CI) (OVII_W_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatOVIIIWOVIII line strength of warm component (OVIII_W) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_OVIIIWOVIII strength of warm component error (90% CI) (OVIII_W_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatO887WOVIII + unresolved OVII line strength, warm (O887_W) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_O887WOVIII + unres OVII line error, warm (90% CI) (O887_W_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatOVIIHOVII line strength of hot component (OVII_H) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensitydoublee_OVIIHOVII strength of hot component error (90% CI) (OVII_H_err) (2)ph.cm**-2.s**-1.sr**-1stat.errordoubleOVIIIHOVIII line strength of hot component (OVIII_H) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_OVIIIHOVIII strength of hot component error (90% CI) (OVIII_H_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatO887HOVIII + unresolved OVII line strength, hot (O887_H) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_O887HOVIII + unres OVII line error, hot (90% CI) (O887_H_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatOVIITTotal OVII line strength (OVII_T) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_OVIITTotal OVII line strength error (90% CI) (OVII_T_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatOVIIITTotal OVIII line strength (OVIII_T) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_OVIIITTotal OVIII line strength error (90% CI) (OVIII_T_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatO887TOVIII + unresolved OVII line strength, total (O887_T) (2)ph.cm**-2.s**-1.sr**-1spect.line.intensityfloate_O887TOVIII + unres OVII line error, total (90% CI) (O887_T_err) (2)ph.cm**-2.s**-1.sr**-1stat.errorfloatLHBEMEmission measure of the LHB (LHB_EM)pc.cm**-6phys.emissMeasuredoublenHTBabs nH parameter (nH)1e+22cm**-2stat.paramfloat