J/A+A/643/A122ivo://CDS.VizieR/J/A+A/643/A122doi:10.26093/cds/vizier.36430122CDSSkoda P.Podsztavek O.Tvrdik P.2022-09-07T09:04:39Z2020-11-11T15:36:05ZCDS support team

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

cds-question@unistra.frsurveysemission-line-starsspectroscopyCurrent archives of the LAMOST telescope contain millions of pipeline-processed spectra that have probably never been seen by human eyes. Most of the rare objects with interesting physical properties, however, can only be identified by visual analysis of their characteristic spectral features. A proper combination of interactive visualisation with modern machine learning techniques opens new ways to discover such objects. We apply active learning classification methods supported by deep convolutional neural networks to automatically identify complex emission-line shapes in multi-million spectra archives. We used the pool-based uncertainty sampling active learning method driven by a custom-designed deep convolutional neural network with 12 layers. The architecture of the network was inspired by VGGNet, AlexNet, and ZFNet, but it was adapted for operating on one-dimensional feature vectors. The unlabelled pool set is represented by 4.1 million spectra from the LAMOST data release 2 survey. The initial training of the network was performed on a labelled set of about 13000 spectra obtained in the 400{AA} wide region around H{alpha} by the 2m Perek telescope of the Ondrejov observatory, which mostly contains spectra of Be and related early-type stars. The differences between the Ondrejov intermediate-resolution and the LAMOST low-resolution spectrographs were compensated for by Gaussian blurring and wavelength conversion. After several iterations, the network was able to successfully identify emission-line stars with an error smaller than 6.5%. Using the technology of the Virtual Observatory to visualise the results, we discovered 1013 spectra of 948 new candidates of emission-line objects in addition to 664 spectra of 549 objects that are listed in SIMBAD and 2644 spectra of 2291 objects identified in an earlier paper of a Chinese group led by Wen Hou. The most interesting objects with unusual spectral properties are discussed in detail.2020A&A...643A.122Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/643/A122CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/146 : LAMOST DR1 catalogs (Luo+, 2015)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/643/A122https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/643/A122http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/643/A122https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/643/A122https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/643/A122http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/643/A122GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/643/A122/cans-new (Spectra of unknown emission stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/643/A122/cans-new?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/643/A122/cans-new?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/643/A122/cans-new?GETtext/xml+votable180.050000true59.01346635.247410.005555555555555556Cone search capability for table J/A+A/643/A122/cans-hou (Spectra identified by both us and Hou et al. (2016RAA....16..138H))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/643/A122/cans-hou?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/643/A122/cans-hou?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/643/A122/cans-hou?GETtext/xml+votable180.050000true97.4216074.889980.005555555555555556Cone search capability for table J/A+A/643/A122/cans-sim (Identified spectra cross-matched with SIMBAD)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/643/A122/cans-sim?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/643/A122/cans-sim?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/643/A122/cans-sim?GETtext/xml+votable180.050000true88.85261722.9101660.005555555555555556Cone search capability for table J/A+A/643/A122/cans-bad (ADL identified bad spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/643/A122/cans-bad?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/643/A122/cans-bad?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/643/A122/cans-bad?GETtext/xml+votable180.050000true224.533483-1.3056920.0055555555555555564/1390-1391 1522-1523 1528 1531 5/277 303 320-321 323-324 326-327 329 333-334 338 340 344 356 358 363-364 389 415 435 451-452 454 480 482-483 486 794 807 834 3493 3683 3698-3699 5363 5549 5701 5909 5918 5931 5941 5948 5952-5954 5995 5999 6010 6039 6045 6047 6081-6086 6099 6104 6106 6116-6118 6120-6121 6123 6/246 257 267 294 303 342 374 377 461 464 472 474 483 488 496 501 504 509 511 781 796 819 833 852 859-860 862 881 905 928 984-985 989-990 992 999 1004 1009 1012 1031 1040 1043 1045-1046 1050 1052 1054 1061 1064 1066 1073-1075 1082-1083 1087 1090 1103 1115 1119 1136 1141-1143 1149-1150 1156-1157 1159 1163 1166-1169 1171 1176 1179 1181 1185-1186 1189 1194 1197 1199 1201 1203 1206-1207 1211 1219 1222 1231 1239-1241 1243-1244 1246 1249-1252 1256 1258-1259 1264 1267-1268 1274 1288-1289 1291 1302-1303 1312-1313 1315 1320-1321 1324-1326 1328-1330 1340-1341 1343 1346 1367 1370-1371 1381 1386-1390 1392-1393 1401-1402 1411-1412 1415 1418-1420 1422-1423 1428-1430 1436 1439 1443 1445-1447 1460 1464-1466 1468-1470 1474 1477 1484 1492 1506-1507 1510 1514 1531-1532 1538-1539 1542 1544-1545 1547 1551-1552 1555 1560-1561 1563-1566 1578 1584 1590 1593 1600-1602 1618 1621 1625 1627-1628 1630 1637 1649-1650 1654 1657 1685 1687 1689 1694 1701 1713 1729 1733 1735 1738-1739 1744 1746-1749 1751-1753 1755-1758 1760-1762 1764-1765 1769 1773 1775 1780-1781 1783 1785 1787-1790 1792 1794 1797 1799-1800 1803 1812 1814-1815 1821 1823 1829-1831 1835 1837 1839-1840 1842-1846 1848-1849 1854 1857 1864 1871 1875 1883 1888 1890 1911 1927 1936 1938-1939 1943 1949-1950 1953 1955-1957 1961 1968 1974 1986 1989 2079 2081 2131 2153-2155 2162 2241 2244 2248 2276 2280 2403-2404 2412 2455 2472 2522 2544 2554 2589 2644 2655 2662 2666 2674 2682-2683 2686 2708-2709 2722 2752 2795 2801 2958 2967 2971 2974-2975 2993 2997 3018-3019 3080 3094 3097-3098 3101 3108 3113 3120 3127 3133-3135 3140-3141 3144-3145 3152-3154 3165 3167 3169-3170 3174 3180 3188-3189 3191 3200 3217 3219 3221 3223 3226 3247 3249-3250 3256-3258 3260 3262 3265-3267 3270 3272 3329-3330 3342 3362 3589-3590 3596 3600-3601 3603-3605 3607 3612 4097 4111 4127 4163 4193 4195-4196 4244 4258 4293 4370 4597 4607 4647 4649 4664 4725 4737-4738 4740 4749 4760 4790 4834 4836 4849-4850 4868 4911 4964 4966-4967 4971 4974 5077 5190-5191 5210 5219 5244 5255 5264 5271 5383-5384 5519 5583 5643 5649 5732 5918 5921 6015 6148 6154 6177 6196 6220 6227 6240 6244 6268 6274 6280 6285 6295 6301 6318 6358 6360 6363-6364 6374 6396 6406 6501 6670 6672 6680 6690 6694 6696 6699 6716 6721 6724 6750 6752 6754 6769 6780 6810 6827 6844 6882 6888 6896 6936 6938 7120 7137 7257 7306 8196 8270 8549 8994 9300 9309 9452 9475 9484 9504 9519 9535 9559 9578 9661 9730 9922 9931 9954 10062 10088 10099 10350 10371 10374 10511 10820 10899 11032 11072 11084 11167 11336 11340 11431 12752 12790-12791 13141 13410 13481 13533-13535 13556 13606 13718 13728 13749 13880 13884 13886-13887 13930 13957 13969 13971 14583 14588-14589 14727 14738 14744 14746-14748 14751 14761 14764-14765 14769-14770 14773 14775 14778 14781 14787 14790 14816 14818 14820 14830 14920 14934 14949 14956 14990 15090 15107 15113 15121 15132-15133 15280 15301 17648 17650 17659 17790 18134 18223 18295 18862 19009 19039 19065 19078 19145 19169 19272 19397 19423 19913 19950 19956 19963 19967 19994 19999 20016 20025 20052-20053 20201 20345 20351 21371 21374-21375 21435 21438-21439 21447 21456-21458 21464 21466 21470 21488 21490-21491 21497 21501 21630 21756-21757 21795 21855 21893 21909 21942-21944 21946 21967 21984 21995 21998 22101-22102 22148 22152 22171-22172 22175 22194-22195 22201 22203 22206-22207 22217-22221 22223 22230 22233-22234 22236 22238-22239 22334 22360-22361 22375 22391 22410-22411 22421 22432-22434 22440-22442 22446-22447 22458 22494 22506 22517 22732 22789 22797 22800-22801 22803 22808-22809 22811-22814 22943 22998-22999 23007 23029-23031 23089 23100 23120 23160 23163-23164 23254 23295 23387 23393-23394 23469 23546 23549 23573 23633 23645 23663 23678-23679 23683 23689 23702 23708-23709 23711 23713 23715-23716 23718-23719 23721 23730 23738-23739 23744 23749 23752 23756-23758 23760 23762-23763 23768-23769 23771-23774 23780 23783 23788-23789 23799 23802-23803 23805-23807 23821 23826 23832 23841 23844 23862 23866-23867 23869-23870 23874 23898 23904-23905 23908 23911 23915-23916 23932-23933 23943 23952 23954-23958 23961-23964 23966-23967 23973 23978 23984 23986-23990 23993-23995 24002-24004 24007-24008 24011 24015-24017 24019 24025-24026 24028 24032 24034 24044-24045 24047 24050 24057 24060-24061 24145 24147-24149 24151 24153 24155 24178-24179 24185 24187 24232 24236-24237 24243 24247-24248 24262 24264-24265 24273 24277 24281-24282 24285-24288 24290 24292 24295-24296 24300 24302 24311 24319-24320 24322-24323 24349 24384-24385 24387 24390 24393 24395 24400-24401 24403-24405 24411-24412 24414 24428 24430 24442-24443 24476-24478 24489-24491 24512-24513 24515-24518 24520-24522 24524-24525 24528 24530-24531 24533-24534 24537 24539 24541 24545 24547-24548 24550-24554 24556-24558 24561-24562 24570 24573-24574 25599 25873 25985 26201 26300 26409 26957 27089 27123 27182 27192 27245 27437 27439 27564 27637 27663 27816 27873 27877 27942 28067 28127 28280 28316 28339 28432 28491 28517 28524 28538 28549 28599 31533 31549 31593 32276 32744 36808 45054https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/643/A122?format=asciidefaultJ/A+A/643/A122/cans-newSpectra of unknown emission starsSpecLLAMOST Spectrum filenamemeta.id;meta.filecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLAMOSTLAMOST Object namemeta.id;meta.maincharRAJ2000LAMOST Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000LAMOST Declination (J2000)degpos.eq.dec;meta.mainSubclassSpectral subclass from LAMOST pipelinesrc.classcharrmag? r magnitude from LAMOST FITS (G1)magphot.mag;em.opt.RfloatnullableClassADLPredicted class by our ADL method (G2)src.classcharGroupID? Group of spectra for a single objectmeta.idintnullableGroupSize? Number of spectra of a single objectmeta.numberintnullableCDS-plotLink to spectrum's plot in CDS Viziermeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/A+A/643/A122/cans-houSpectra identified by both us and Hou et al. (2016RAA....16..138H)SimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpecLLAMOST Spectrum filenamemeta.id;meta.filecharLAMOSTLAMOST Object namemeta.id;meta.maincharRAJ2000LAMOST Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000LAMOST Declination (J2000)degpos.eq.dec;meta.mainSubclassSpectral subclass from LAMOST pipelinesrc.classcharrmag? r magnitude from LAMOST FITS (G1)magphot.mag;em.opt.RfloatnullableClassADLPredicted class by our ADL method (G2)src.classcharSNameSIMBAD name of cross-matched objectmeta.idcharSMainTypeObject type as given in SIMBADsrc.classcharSSPTypeSpectral type from SIMBADsrc.spTypecharHouObject name given by Hou et al. (2016RAA....16..138H)meta.idcharRAHdegRight ascension (J2000) by Hou et al. (2016RAA....16..138H)degpos.eq.raDEHdegDeclination (J2000) by Hou et al. (2016RAA....16..138H)degpos.eq.decHalphaTypeType of line profile by Hou et al. (2016RAA....16..138H)meta.notecharObjTypeType of object by Hou et al. (2016RAA....16..138H)src.classcharGroupID? Group of spectra for a single objectmeta.idintnullableGroupSize? Number of spectra of a single objectmeta.numberintnullableCDS-plot2Link to spectrum's plot in CDS Viziermeta.ref.urlcharJ/A+A/643/A122/cans-simIdentified spectra cross-matched with SIMBADSNameSIMBAD name of cross-matched objectmeta.idcharRASdegSIMBAD Right ascension (J2000)degpos.eq.raDESdegSIMBAD Declination (J2000)degpos.eq.decSMainTypeObject type as given in SIMBADsrc.classcharSSPType? Spectral type from SIMBADsrc.spTypecharAngDistAngular distance of cross-match (1)arcsecpos.angDistancedoubleGroupID? Group of spectra for single objectmeta.idintnullableGroupSize? Number of spectra of single objectmeta.numberintnullableCDS-plot3Link to spectrum's plot in Viziermeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpecLLAMOST Spectrum filenamemeta.id;meta.filecharLAMOSTLAMOST Object namemeta.id;meta.maincharRAJ2000LAMOST Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000LAMOST Declination (J2000)degpos.eq.dec;meta.mainSubclassSpectral subclass from LAMOST pipelinesrc.classcharrmag? r magnitude from LAMOST FITS (G1)magphot.mag;em.opt.RfloatnullableClassADLPredicted class by ADL method (G2)src.classcharJ/A+A/643/A122/cans-badADL identified bad spectrarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpecLLAMOST Spectrum filenamemeta.id;meta.filecharLAMOSTLAMOST Object namemeta.id;meta.maincharRAJ2000LAMOST Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000LAMOST Declination (J2000)degpos.eq.dec;meta.mainSubclassSpectral subclass from LAMOST pipelinesrc.classcharSimbadSimbad column added by the CDSmeta.ref.urlcharrmag? r magnitude from LAMOST FITS (G1)magphot.mag;em.opt.RfloatnullableClassADLPredicted class by our ADL method (G2)src.classcharGroupID? Group of spectra for a single objectmeta.idintnullableGroupSize? Number of spectra of a single objectmeta.numberintnullableCDS-plotLink to spectrum's plot in CDS Viziermeta.ref.urlchar