J/A+A/710/A77ivo://CDS.VizieR/J/A+A/710/A77CDSMoysan Q.Sarron F.Clerc N.Soucail G.Adami C.Altieri B.,Cabanac R.Chira M.Comparat J.Coia D.Drigga E.Gaynullina E.,Khalikova A.Koulouridis E.Migkas K.Molham M.Paquereau L.,Sadibekova T.Valtchanov I.2026-07-08T07:16:58Z2026-06-03T08:01:11ZCDS support team

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

cds-question@unistra.frx-ray-sourcesgalaxy-clustersredshiftedProperties of the hot intracluster and intragroup medium are mostly set by the underlying gravitational potential well, although complex astrophysical processes at play during their buildup may leave a significant imprint. Observational constraints on the degree and scales of such nongravitational processes require well-selected samples of objects and deep observations of their gas content. We aim to study the scaling relation between two global properties of the hot gas, namely its soft-band X-ray luminosity (L_X_) and its temperature (T), by studying a sample of low-mass systems associated with precise redshifts, simultaneously accounting for sample selection biases and associated measurement uncertainties. This work takes as input a large catalog of X-ray-selected galaxy clusters (X-CLASS). We performed a thorough revision of the redshifts of sources using deep photometric data from the Legacy Surveys and our own tailored spectroscopic follow-up of 52 low-redshift systems. We devised a spectroscopically complete sample of 155 low-redshift (0.07<z<0.2) systems, and we measured properties of their X-ray emitting gas, with median ^-^T=1.7keV and median ^-^L_X_=10^43^erg/s. We inferred the relation between L_X_ and T in a Bayesian framework. Our sample of groups and clusters with a median total mass of ~6x10^13^M_{sun}_ reveals a relation L_X_-T steeper than that predicted by the self-similar model, with a slope of B=3.2+/-0.1. This result fits well within recent studies that together indicate a trend of an increasing slope with decreasing median halo mass. This work supports a scenario of a stronger decrease in luminosity with decreasing mass in the group regime than for massive galaxy clusters. This effect is possibly due to strong and sustained feedback expelling gas efficiently from their shallower potential wells. We release the list of updated redshifts (photometric and spectroscopic) for the full X-CLASS sample and the gas properties of the low-redshift sample. The cluster photometric redshift code presented in the paper photXclus is made publicly available (https://codeberg.org/fsarron/photXclus).2026A&A...710A..77Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/710/A77CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/494/161 : The X-CLASS-redMaPPer galaxy cluster sample (Molham+, 2020)J/A+A/652/A12 : The new X-Class catalogue (Koulouridis+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/710/A77https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/710/A77http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/710/A77https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/710/A77https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/710/A77http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/710/A77GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/710/A77/tableb1 (Results of the MISTRAL observing runs at OHP)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/710/A77/tableb1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/710/A77/tableb1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/710/A77/tableb1?GETtext/xml+votable180.050000true68.5873-8.49080.005555555555555556Cone search capability for table J/A+A/710/A77/tablec1 (Redshift of the 52 X-CLASS clusters measured with MISTRAL)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/710/A77/tablec1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/710/A77/tablec1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/710/A77/tablec1?GETtext/xml+votable180.050000true68.5703-8.51240.005555555555555556Cone search capability for table J/A+A/710/A77/tablec2 (The 1599 X-CLASS galaxy clusters with updated redshifts (z), associated flags and confirmation status)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/710/A77/tablec2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/710/A77/tablec2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/710/A77/tablec2?GETtext/xml+votable180.050000true193.43810.19540.005555555555555556Cone search capability for table J/A+A/710/A77/tabled1 (List of the 155 galaxy clusters constituting the X-CLASS-LR and their measured physical properties (corrected version, 08-Jul-2026))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/710/A77/tabled1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/710/A77/tabled1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/710/A77/tabled1?GETtext/xml+votable180.050000true145.93816.73810.0055555555555555565/4423 11545 6/50 87 97 148-149 246 306 419 463 474 597 619-620 932 941 948 953 2111 2125 2154 2164 2227 2230 2248 2251 2340 2342 2432 2436 2466 2591 2634 3934 4078 4088 4146 4181 4206 4221 4227 4303 4313 4340 4344 4347 4352 4369 4381 4403 4409 4438-4439 4448 4450 4567 4629 4688-4689 4697 4720 4748 4804 4807-4808 4821 4831 4834 4867 4921 4924 4939 4943 4953-4955 4964-4965 4967 4976-4977 5018 5033 5091 5099 5109 5112 5130 5241 5305 5312-5313 5369-5370 5373 5420 5429 5438 5471 5536 5545 5568-5569 5587 5604 5618 5629-5630 5646 5670 5675 5699 5701 5727 5733 5749 5762 5792-5793 5795 5817 5847 5860 5862 5937 5939 5952 5975 5980 6033 6051 6056-6057 6069 6077 6098 6219 6247 6337 6348 6382-6383 6417 6441 6459 6472 6494 6539 6544-6545 6561 6574 6618-6619 7004 7026 7047 7178 7235 7240 7242 7273 7280-7281 7309-7310 7363 7448 7485 7510 7513 7525 7536 7552 7576 7604 7612 7661 7682 7695 7799 7872 7896 7904 7923 7941 7969 8028 8033 8066 8072 8106-8107 8173 8195-8196 8199 8220 8225 8245 8261 8264 8268 8271 8288 8339 8440 8442 8537 8575 8644 8673 8724 8788 8809 8845 8909 8921 8926-8927 8952 8956 8969 9036 9052 9060 9072 9074 9077 9146 9150-9151 9168 9276 9287 9343 9354 9366 9428 9467-9469 9476 9496 9498 9504 9524 9588 9593 9632 9703 9764 9811 9815 9831 9925 9988 9997 10141 10167 10183 10190 10201 10218 10223 10255 10271 10312 10321 10347 10378-10379 10383 10391 10413-10414 10422 10434-10435 10442 10444 10484 10527 10544 10549 10551 10598-10599 10637 10645 10657 10664 10691 10761 10905 10912 10936 10938 11000 11029 11048 11080 11084 11112 11130 11158 11208 11217 11249 11264 11314 11347 11463 11596 11603 11624 11626 11636 11664 11810 11831 11845 11924 11931-11933 12002 12025 12045 12060 12121 12123 12134 12180 12185 12317 12336 12642 13314 13511 13529 15026 15286 15295 15915 16024 16031 16056 16059 16062 16410-16411 16432-16434 16437 16441 16444 16486 16490 16492 16500 16506 16509-16510 16543 16591 16609 16642 16655-16657 16661 16666 16713 16806 16831 16834 16890 17130 17141 17188 17237 17264 17300 17307 17357 17398 17438 17450 17456-17457 17472 17497 17508-17509 17511 17518 17525 17582 17593 17622 17662 17678-17679 17682-17683 17686 17689-17691 17697 17712-17714 17716 17749 17767 17772 17797 17812 17840-17841 17866 18003 18009 18011 18016 18071 18073 18084 18090 18099 18110 18112 18114 18127 18153 18184 18207-18209 18302 18335 18367 18410-18411 18456 18475 18534 18566 18584-18585 18596 18601 18607 18639 18642 18683 18742 18757 18779 18784 18789-18791 18796 18894 18948 18968 19009 19036 19091 19094 19097 19101 19151 19177 19269 19462 19470 19506 19519 19542 19608 19694 19776 19802 19842 19846-19848 19851 19904-19905 19935 19950 19990 20021 20055 20061 20071 20073 20075 20083 20168 20386 20481 20507 20511 20520 20537 20591 20624 20706 21033 21072-21073 21133 21135 21169 21233 21387 21851 21854 21870 21970 22366 22537 22577 22607 22659 22721-22722 22746 22771 22792 22915 22936 22972 23042 23050 23149 23169 23176 23178 23209-23210 23223 23259 23275 23306 23451 23526 23529 23545 24577 24579 24615 24622 24822 24829 24831 24853 24943-24944 24949 24951 24958 25005 25042 25055 25068 25077 25079 25081 25084 25086 25166 25188 25344 25416 25418 25451 25478 25540 25563 25585 25587 25630 25635 25658 25669 25675 25682 25743 25769 25787 25789 25852 25912 25919 25952 25954 25974 25981-25982 25990 26022 26037 26055 26100 26175 26185 26189 26195 26208 26242 26268 26292 26299 26302 26331 26370 26540 26561 26563 26569 26590 26628 26645 26677 26690 26694 26746 26749 26785 26787 26802 26808 26839 26866-26867 26902 26922 26936 26946 26975 26990 26998 27004 27009 27041 27043 27055 27060 27075 27088 27102 27122 27127 27132 27179 27225 27228 27235 27246 27256 27258-27259 27308 27314 27342 27351 27412 27428 27440 27460 27462 27466 27474 27480 27504-27505 27580 27617 27664 27719 27731-27732 27734 27738 27740 27742 27760 27765 27785 27857 27918 27941 27944 27948 27961 27966 28022 28026 28029 28036 28045 28054 28063 28085 28126-28127 28141-28142 28148 28174 28188 28275 28278 28346 28351 28427 28430 28443 28448 28467 28471 28476 28492 28495 28497 28522 28535 28583 28589 28609 28611 28621 30028-30029 30903 30916 30946 31122 31313 31316 31396 31398 31430 31465 31495 31509 31537 32362 32463 32500 32721 32739 32892 32908 32960 32994 33004 33030 33152-33153 33176 33235 33261 33265 33273 33433 33502 33573 33578 33586 33593 33618-33620 33625 33628 33630 33649 33668 33670 33692 33709 33712-33713 33716 33795 33804 33810 33891 33894 33912 33917 33944-33945 33960 33971 33980 33984 33986 34049 34054 34070 34083 34087 34161 34181 34186 34191 34258 34264 34297 34382 34423 34443 34463 34480 34485 34496 34520 34531 34534-34535 34580 34653 34737 34805 34905 34910 34994 35049 35055-35056 35067 35097 35099 35161 35171 35180 35206 35230 35266 35272 35343 35390 35393 35473 35536 35565 35576 35691 35755 35927 35935 35969 35985 36006 36012 36031 36066 36082 36098 36132 36141 36152 36172 36232 36290 36393 36417 36423 36434 36459 36534 36713 36792 36846 37022 37406 37545 37547 38359 38714 38853 38946 38973 39047 39067-39068 39077 39079 39462 39608 40216 40279 40294 40402 40433 40446 40776-40777 40803 40809 40823 40956 40987 41014 41088 43477 43503 43506 43518 43626 43757 43785 43787 43815 43828 43830 43836-43838 43849 43860 43891 43939 43941 43945 43947-43948 43950 43952 44008 44169 44247 44502 44518 44554 44833 44836 44861 44947 45242 45305 45348 45421 45423 45485 45497 45506 45542-45543 45584 45636 45686 45692 45741 45754 45821 45841 45860 45873 45887 45893 45904 45906 45942 45957 45962 45964-45965 45970 45973 45981 45984 46017 46020 46046 46079 46101 46105 46108 46130 46157-46159 46166 46170 46177 46179 46237 46344-46345 46399 46424 46442 46474 46477 46484 46548 46608 46642 46687 46739-46740 46807 46855 46882 46889 46969 46987 47005 47007 47016 47043 47053 47168 47178 47188 47199 47225 47314 47331 47347 47368 47370 47417 47419 47430 47573 47941 48076 48171 48179 48258 48346 48423 48478-48479 48483-48484 48489 48501-48502 48639 48688 48735 48738 48966 49012 49043 49125https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/710/A77?format=asciiX-raydefaultJ/A+A/710/A77/tableb1Results of the MISTRAL observing runs at OHPrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalIDGalaxy identification including the X-CLASS number, xclassNNNN-GNmeta.id;meta.maincharRAJ2000Right ascension (J2000.0)degpos.eq.ra;meta.mainDEJ2000Declination (J2000.0)degpos.eq.dec;meta.maingmag? g-band magnitudephot.mag;em.opt.Bfloatnullablermag? r-band magnitudephot.mag;em.opt.Rfloatnullablezphot? Photometric redshiftsrc.redshiftfloatnullablezspecSpectroscopic redshiftsrc.redshiftfloatQ[1/3] Confidence level (1)meta.code.qualintComCommentsmeta.notecharJ/A+A/710/A77/tablec1Redshift of the 52 X-CLASS clusters measured with MISTRALrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintXClass[297/24762] X-CLASS numbermeta.id;meta.mainintRAJ2000Right ascension (J2000.0)degpos.eq.ra;meta.mainDEJ2000Declination (J2000.0)degpos.eq.dec;meta.mainzRedshiftsrc.redshiftfloatS[2/5] Redshift quality flag (1)meta.code.qual;src.redshiftintJ/A+A/710/A77/tablec2The 1599 X-CLASS galaxy clusters with updated redshifts (z), associated flags and confirmation statusrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintXClass[20/24821] X-CLASS catalogue unique identifiermeta.id;meta.mainintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainz? Redshift value associated to the galaxy clustersrc.redshiftfloatnullableZSPThree-digit ZSP flag associated to the cluster redshift measurementmeta.codeintStatusRedshift quality statusmeta.code.qualcharJ/A+A/710/A77/tabled1List of the 155 galaxy clusters constituting the X-CLASS-LR and their measured physical properties (corrected version, 08-Jul-2026)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintXClass[54/24762] X-CLASS name from the X-CLASS cataloguemeta.id;meta.mainintRAJ2000Right Ascension (J2000.0)degpos.eq.ra;meta.mainDEJ2000Declination (J2000.0)degpos.eq.dec;meta.mainzSpectroscopic redshift of the clustersrc.redshiftfloatT? Spectroscopic temperature measurementkeVphys.temperaturefloatnullableE_T? Spectroscopic temperature positive uncertaintykeVstat.error;stat.maxfloatnullablee_T? Spectroscopic temperature negative uncertaintykeVstat.errorfloatnullableZ? Metallicity measurementSunphys.abund.Zdoublenullablen_Z[*] * indicates fixed metallicitymeta.notecharE_Z? Metallicity positive uncertaintySunstat.error;stat.maxfloatnullablee_Z? Metallicity negative uncertaintySunstat.error;src.redshiftdoublenullableL500? Luminosity L500 measurements in 10^42^erg/s1e+35Wphys.luminosityfloatnullableE_L500? Luminosity L500 positive uncertainty in 10^42^erg/s1e+35Wstat.error;stat.maxfloatnullablee_L500? Luminosity L500 negative uncertainty in 10^42^erg/s1e+35Wstat.errorfloatnullableR500? Radius R500 of the cluster derived from scaling relationkpcphys.size.radiusintnullablechi2/nuGoodness of the backgroung estimation of the pointingstat.fit.goodnessfloat