IV/35ivo://CDS.VizieR/IV/35CDSWilson T.J.Naylor T.2023-12-20T12:28:30Z2018-10-03T16:25:06ZCDS support team

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

cds-question@unistra.frastrometryastronomical-object-identificationgalaxy-planesmilky-way-galaxyphotometryFaint, hidden contaminants in the point-spread functions (PSFs) of stars cause shifts to their measured positions. Wilson & Naylor (2017MNRAS.468.2517W) showed failing to account for these shifts can lead to a drastic decrease in the number of returned catalogue matches in crowded fields. Here we highlight the effect these perturbations have on cross-matching, for matches between Gaia DR2 and WISE stars in a crowded Galactic plane region. Applying the uncertainties as quoted to Gaussian-based astrometric uncertainty functions (AUFs) can lead, in dense Galactic fields, to only matching 55% of the counterparts. We describe the construction of empirical descriptions for AUFs, building on the cross-matching method of Wilson & Naylor (2018MNRAS.473.5570W), utilising the magnitudes of both catalogues to discriminate between true and false counterparts. We apply the improved cross-matching method to the Galactic plane |b|<10. We provide the most likely counterpart matches and their respective probabilities. We also analyse several cases to verify the robustness of the results, highlighting some important caveats and considerations. Finally, we discuss the effect PSF resolution has by comparing the intra- catalogue nearest neighbour separation distributions of a sample of likely contaminated WISE objects and their corresponding Spitzer counterpart. We show that some WISE contaminants are resolved in Spitzer, with smaller intra-catalogue separations. We have highlighted the effect contaminant stars have on WISE, but it is important for all photometric catalogues, playing an important role in the next generation of surveys, such as LSST.2018MNRAS.481.2148Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/IV/35CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)II/328 : AllWISE Data Release (Cutri+ 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=IV/35https://vizier.iucaa.in/viz-bin/VizieR-2?-source=IV/35http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=IV/35https://vizier.cds.unistra.fr/viz-bin/votable?-source=IV/35https://vizier.iucaa.in/viz-bin/votable?-source=IV/35http://vizieridia.saao.ac.za/viz-bin/votable?-source=IV/35GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table IV/35/wn18_b10 (IDs, positions, magnitudes and probabilities (118,964,029 sources))https://vizier.cds.unistra.fr/viz-bin/conesearch/IV/35/wn18_b10?https://vizier.iucaa.in/viz-bin/conesearch/IV/35/wn18_b10?http://vizieridia.saao.ac.za/viz-bin/conesearch/IV/35/wn18_b10?GETtext/xml+votable180.050000true74.829525362991226.23625168338180.0055555555555555563/20 22 27-28 30 47 49-51 56-58 202-203 206-207 218-219 222-225 228-229 240-241 244-245 325 336 338 344-345 347 369 371-372 374 377 380 382-383 455 460-461 472-473 475 478-479 501 581 583 589 591-592 594 600 602 613 615 621 623-624 626 632 634 649-654 658-659 662 664 672 4/69 71 77 79 84-86 92 94 101 103 116 181-183 186-187 193 195 208-210 216 218 236 882-883 885-887 904-905 908-909 920-921 924-925 968-969 972-973 984-985 1309 1311 1333 1348 1350 1356 1358-1359 1384-1385 1387 1394 1400 1402 1473 1475 1500 1502 1517 1519 1524 1526-1527 1792-1793 1796 1799 1810-1811 1817 1819 1824 1830-1831 1852-1853 1866-1867 1870 1896-1897 1899 1904 1906-1907 1910-1911 1989 2000-2001 2329 2331 2353 2355 2361 2363 2372-2374 2380 2382 2449 2451 2457 2459 2481 2483 2489 2491 2542 2586-2587 2589-2591 2595 2620-2621 2631 2642-2643 2645-2646 2652 2660-2661 2672-2673 2676-2677 2692-2694 2696 2698 5/273 275 281 283 305 307 313 315 348-350 372 374 380 401 403 409-411 429 431 472 474 496 498 637 639 703 723 741-743 777 779 844 846 868 870 948-950 952-954 960-962 968 1706 3208 3210-3211 3214-3215 3226-3227 3455 3471 3482-3483 3485-3487 3526-3527 3537-3539 3640-3641 3644-3645 3688-3689 3692-3693 3704-3705 3708-3709 3880-3881 3884 3952-3954 3956 5189 5191 5232-5233 5235 5241 5243 5341 5343 5365 5404 5406 5428 5430-5431 5482 5544-5545 5547 5568 5570 5604 5606 5612 5614-5615 5889 5891 5924-5925 5927 5933 5935 5970 5976 5978 6014 6065 6067 6073 6075 6100 6102 7177 7180-7181 7190-7193 7234 7258-7259 7262 7265 7267 7273-7275 7300 7302-7305 7308-7309 7314-7315 7318-7319 7392-7393 7396-7397 7399 7420-7421 7456 7458-7459 7462-7463 7486-7487 7530 7592-7593 7595 7620 7622-7623 7634-7635 7941 7952-7953 8008-8009 8012-8013 8015 8052-8053 9287 9293-9295 9443 9449 9451 9500-9502 9524 9526 9536 9616-9618 9624 9626 9648 9793 9795 9801 9803 9825 9827 9833 9835 9921 9923 9929 9931 10136 10138 10160 10162 10299 10301-10303 10342-10343 10354-10355 10373-10375 10377-10379 10488-10489 10510-10511 10522-10523 10563 10566-10567 10577-10579 10588 10616 10618 10648-10650 10652-10653 10656-10657 10696-10697 10700-10701 10712-10713 10716-10717 10780 10788-10790 10816-10817 10880 11946 6/1404-1406 1492 1494 1528 1530 1603 1609 1611 1633-1635 1685 1687 1693-1695 1715 1721 1723 1872 1874 1892-1894 1900 1902 1988 2016-2018 2024 2026 2525 2527 2547 2553-2555 2807 2811 2871 2877-2879 2885 2887 2891 2955 2957-2959 2961-2963 3085 3087 3113 3115 3380-3382 3388 3390 3392 3504 3506 3512 3804 3820 3824 3852 3854 3880 3882 6784 6786 6792 6794 6816 6818 6830 12836 12838-12839 12850-12851 12854 12922-12923 12926-12927 13098-13099 13807 13814-13815 13817-13819 13867 13870-13871 13882-13883 13926-13927 13938-13939 14091 14094-14095 14103 14145-14147 14512-14513 14516-14517 14519 14584-14585 14588-14589 14760-14761 14764-14765 14776-14777 14780-14781 14824 15540-15542 15584-15585 15588-15589 15600-15601 15604-15605 15776-15777 15780-15781 15820-15821 15828-15830 15832 20753 20755 20761 20788-20789 20791 20797 20799 20936-20937 20939 20961 21317 21319 21360-21361 21363 21369 21469 21471 21584 21586 21592 21594-21595 21628 21630 21716 21718-21719 21898 21920 21922 22184-22185 22187 22278 22284 22286-22287 22328 22330 22430 22452 22454-22455 23553 23555 23589 23591 23597 23705 23707 23729 23872 23874 23910 23916 23918 24024 24026 24048 24050-24051 24085 24087 24093 24095 24257 24259 24265 24267 24289 24404 24406 24412 24414 28704-28705 28754-28755 28758-28759 28776-28777 28780-28781 28885 28940 28942-28943 28954-28955 29026-29027 29030 29054-29057 29059 29065 29067 29089-29091 29204 29206-29207 29229 29240-29241 29244-29245 29250-29251 29254 29269 29271 29392-29393 29396-29397 29581 29592-29593 29665 29668-29669 29692-29693 29828 29830-29831 29842 29898-29899 29936 29938-29939 29942 30126-30127 30138 30376-30377 30379 30484 30486-30487 30530-30531 30552 30554-30555 30558-30559 31760-31761 31817 31820-31821 31823 31860-31861 32045 32056-32057 32059 32192-32193 32196-32197 32199 32217 32220-32221 37141-37143 37147 37169 37171 37285 37287 37293 37295 37637 37639 37645 37647 37669 37671 37677 37679 37765-37767 38012-38014 38100 38128 38130 38136 38148 38150 38152-38154 38176 38476 38478 38500 38502 38600 38602 38624 38626 38632 39211 39297 39299 39305 39307 39329 39331 39337 39339 39681 39683 39689 39691 39812-39813 39815 39821 39823 40168 40170 40512 40514 40520 40522 40646 40652 40654 41194-41195 41202-41203 41343 41355 41358-41359 41410-41411 41413-41415 41487 41491 41507 41960-41961 41968-41969 42026-42027 42029-42031 42039 42078-42079 42082-42083 42085-42087 42250-42251 42262-42263 42305-42307 42356-42357 42360-42362 42448 42450 42468-42470 42476 42478-42479 42490-42491 42494-42495 42604-42606 42616-42617 42620 42632-42633 42636 42640-42642 42644-42645 43124-43125 43128 43164-43166 43184-43186 43192 43200-43202 43204 43272-43274 43276 43280-43281 43524 43528 47778 47790-47791 47802-47803 47806-478071.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/IV/35?format=asciidefaultIV/35/wn18_b10IDs, positions, magnitudes and probabilities (118,964,029 sources)RAICRSRight Ascension of Gaia source (ICRS at epoch 2015.5), as given by the Gaia DR2 catalogue (GAIA_RA)degpos.eq.ra;meta.mainDEICRSDeclination of Gaia source (ICRS at epoch 2015.5), as given by the Gaia DR2 catalogue (GAIA_DEC)degpos.eq.dec;meta.mainGAIA-WISEDisplay the Gaia DR2 (Cat. I/345) and AllWISE (Cat. II/328) datameta.ref.urlcharGAIAID of Gaia source, as given by the Gaia DR2 catalogue (GAIA_ID)meta.id;meta.mainindexedWISEID of WISE object, as given by the AllWISE catalogue (WISE_ID)meta.id.crosscharindexedRAWdegRight Ascension of WISE source (J2000), as given by the AllWISE catalogue (WISE_RA)degpos.eq.raDEWdegDeclination of WISE source (J2000), as given by the AllWISE catalogue (WISE_DEC)degpos.eq.decgmagGaia G magnitude, as given by the Gaia DR2 catalogue (G_MAG)magphot.mag;em.optdoubleW1magWISE w1mpro magnitude, as given by the AllWISE catalogue (W1_MAG)magphot.mag;em.IR.3-4umfloatW2magWISE w2mpro magnitude, as given by the AllWISE catalogue (W2_MAG)magphot.mag;em.IR.4-8umfloatW3magWISE w3mpro magnitude, as given by the AllWISE catalogue (W3_MAG)magphot.flux.density;em.IR.8-15umfloatW4magWISE w4mpro magnitude, as given by the AllWISE catalogue (W4_MAG)magphot.flux.density;em.IR.15-30umfloatMatchPOverall probability that the Gaia and WISE sources are detections of the same object, as given by equation 26 of Wilson & Naylor (2018MNRAS.473.5570W) (MATCH_P)stat.fit.goodnessdoubleetaPhotometric logarithmic likelihood ratio of Gaia-WISE match, as described by equation 37 of Wilson & Naylor (2018MNRAS.473.5570W) (ETA)stat.likelihood;phot;arith.ratiodoublexiAstrometric logarithmic likelihood ratio of Gaia-WISE match, as described by equation 38 of Wilson & Naylor (2018MNRAS.473.5570W) (XI)stat.likelihooddoubleContP1Probability of WISE source having contaminant of at least 1% relative flux given its separation from its corresponding Gaia detection, as given by equation 12 of Wilson & Naylor (2018b, this paper) (CONT_P1)stat.fit.goodnessdoubleContP10Probability of WISE source having contaminant of at least 10% relative flux given its separation from its corresponding Gaia detection (CONT_P10)stat.fit.goodnessdoubleavgContMean contaminating relative flux within PSFs when constructing h_offsets for WISE sources at the local density, magnitude and intrinsic positional uncertainty of the primary source (AVG_CONT)stat.fit.goodnessdouble