J/ApJ/942/22ivo://CDS.VizieR/J/ApJ/942/22doi:10.26093/cds/vizier.19420022CDSCampbell H.Khilfeh E.Covey K.R.Kounkel M.Ballantyne R.Corey S.,Roman-Zuniga C.G.Hernandez J.Martinez E.M.Ramirez K.P.,Roman-Lopes A.Stassun K.G.Stringfellow G.S.Borissova J.,Chojnowski S.D.Ramirez-Preciado V.Kim J.S.Serna J.Stutz A.M.,Lopez-Valdivia R.Suarez G.Ybarra J.E.Longa-Pena P.,Fernandez-Trincado J.G.2025-02-24T20:13:45Z2024-12-30T10:20:17ZCDS support team

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

cds-question@unistra.frinfrared-astronomyspectroscopysurveysyoung-stellar-objectsline-intensitiesVery young (t<~10Myr) stars possess strong magnetic fields that channel ionized gas from the interiors of their circumstellar disks to the surface of the star. Upon impacting the stellar surface, the shocked gas recombines and emits hydrogen spectral lines. To characterize the density and temperature of the gas within these accretion streams, we measure equivalent widths of Brackett (Br)11-20 emission lines detected in 1101 APOGEE spectra of 326 likely pre-main-sequence accretors. For sources with multiple observations, we measure median epoch-to-epoch line strength variations of 10% in Br11 and 20% in Br20. We also fit the measured line ratios to predictions of radiative transfer models by Kwan & Fischer. We find characteristic best-fit electron densities of n_e_=10^11^-10^12^cm-3, and excitation temperatures that are inversely correlated with electron density (from T~5000K for n_e_~10^12^cm^-3^ to T~12500K at n_e_~10^11^cm^-3^). These physical parameters are in good agreement with predictions from modeling of accretion streams that account for the hydrodynamics and radiative transfer within the accretion stream. We also present a supplementary catalog of line measurements from 9733 spectra of 4255 Brackett emission-line sources in the APOGEE Data Release 17 data set.2023ApJ...942...22Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/942/22CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIII/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)III/286 : APOGEE-2 DR17 final allStar catalog (Abdurro'uf+, 2022)J/ApJ/794/125 : IN-SYNC. I. APOGEE stellar parameters (Cottaar+, 2014)J/AJ/149/7 : SDSS-III/APOGEE. I. Be stars (Chojnowski+, 2015)J/ApJ/799/136 : IN-SYNC. II. Candidate young stars in NGC 1333 (Foster+, 2015)J/ApJ/818/59 : IN-SYNC. IV. YSOs in Orion A (Da Rio+, 2016)J/AJ/151/144 : ASPCAP weights for 15 APOGEE chemical elements (Garcia+, 2016)J/ApJS/236/27 : APOGEE-2 survey of Orion Complex (OSFC). I. (Cottle+, 2018)J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)J/ApJ/893/56 : T Tauri star IR excesses & Ha EWs (Manzo-Martinez+, 2020)J/ApJS/247/17 : Massive stars in APOGEE2 Survey. III. (Roman-Lopes+, 2020)J/ApJ/914/28 : G305 star-forming region. II. Irregular var. (Medina+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/942/22https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/942/22http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/942/22https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/942/22https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/942/22http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/942/22GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/942/22/table2 (Line measurements for APOGEE DR17 Br11 emitters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/942/22/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/942/22/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/942/22/table2?GETtext/xml+votable180.050000true0.17443555.722443060.0055555555555555564/1802-1804 5/814 825 876 878 1466 2545 3661 3672-3673 5715 5909 7061 7179 7182-7183 7194-7195 7202-7203 7205-7207 7220 7222-7225 7227 7273 7275 7278-7279 7297 7300 7312-7313 7364-7365 7376-7377 7380 7382 7564 8263 8268-8269 8272 8274-8275 8277-8281 8448 9341 9384 9386 9482 10822 6/317 473 475 860 862 881 1031 1050-1051 1054 1061 1063 1082 1113 1118 1137 1145 1150 1159 1168 1176 1231 1264 1305 1310 1453 1538-1539 1542 1958 1960 2154-2155 2241 2263 2434 2436 2439 2615 2622-2623 2625 2665-2666 2705 2708-2709 2752 2805 2955 2987 2990 3024 3045-3046 3058 3060 3062 3100 3250-3251 3254 3260-3262 3290 3305-3309 3312 3314 3320 3353-3354 3478 3495 3501 3508 3510 3516 3595 3605 3607 3615-3616 3621-3623 3631-3632 3635 3644 3648-3649 3651 3658 3680 3715 3735 3737 3751 3945-3947 4032 4071 4075 4077 4255 4295 4298 4315 4322 4623 4685 4844 4932 4934-4935 4940-4941 4944 5138 5144-5145 5147 5250-5251 5256 5665 5676 5681 5821-5823 5858 5910 5913 5919 5937 5974-5975 5985 6248 6251 6575 6822 7189 7232 7286 7334 7938 7945-7946 8358 8567 8575 8739 8745-8748 8750 8846 8864 8963 9180 9221 9235 9250 9256-9257 9301 9303 9308 9356 9425 9434-9436 9665 9668 9938 9944 9958 10086 10095 10123 10188 10190 10192 10315 10336 10374 10750 10855 11069 11130 11410 11452 11686 11690-11692 11729 11981 11996 12032-12033 12391 12399 12403-12404 12406 12481 12914-12915 12955 12967 12981 12987-12988 13024 13111 13167 13581 13799 13802 13808 13915 14003-14004 14006 14031-14032 14040 14047-14048 14067-14068 14077 14079 14085 14173 14190 14197 14217 14220 14249 14251 14258 14272 14285 14307 14309 14314-14315 14430 14443 14469 14529 14573 14591 14619 14622-14623 14640-14641 14643 14652 14666-14667 14670-14671 14680 14682-14683 14696-14697 14700 14704-14705 14754 14819 14827 14950 15105 15131 15137 15139 15171-15172 15388 15407 15418 15429 15433 15445-15446 15486-15487 15608 15610 15612 15618 15632 15649 15668 15690 15702-15703 15799-15800 15929 16692 16800 16892 17174 17224 17293 17296 17298-17299 17306 17331 17585 17610 17671 17746 17816-17817 18008 18024 18061 18067 18126 18350-18351 18413 18482-18483 18606 18617-18618 18779 19044 19457 19694 19755 21011 21400 21402 21425 21428 21430 21436 21438-21439 21534 21558 21673 22029 22041 22044 22046 22078-22079 22087 22121-22122 22210 22243 22246 22249 22517 22804-22805 22807 22848 22851 22854-22855 22857 22873 22875-22876 22881 22884-22885 22896 22906-22907 23061 23209 23482 23549 23632 23704 23706 23717 23727 23736 23739 23755 23767 23778 23905 23946 23949 23976 23980 24066 24081 24116 24180 24182 24271 24281-24283 24293 24304 24325-24326 24345 24359 24368 24376 24442 24466 24483 24490 24505 24512 24968 25391 25431 25512 25560 25616 25627 25638-25639 25644 25656 25693 25802 25850 26020 26022 26025 26028-26029 26114 26177 26273 26276 26280 26347 26600 26922 26974-26975 27009-27011 27014 27017 27020 27085 27105 27205 27207 27460 27462 27513 27515 27582 27608 27623-27624 27634 27679 27706 27902 27905 27910-27911 27916-27917 27937 27975 27992 28243 28252-28253 28290 28418 28424 28550 28599 28618 28640 28642 28646 28649 28685 28690 28696 28698-28699 28705 28707 28709-28711 28713-28715 28722-28723 28726-28727 28744-28745 28758 28763-28764 28770-28771 28774 28788 28792 28794-28795 28801-28805 28807 28816-28818 28904-28905 28907 28912-28914 28917-28920 28922-28924 28926 28943 28973 28984 29003-29004 29023 29033 29043 29065 29070-29071 29089-29091 29096 29104 29107-29108 29110-29111 29155 29159-29161 29163 29166 29170 29179 29183-29185 29187 29199 29205-29207 29211 29216 29218 29232 29243 29256 29260-29262 29269 29271 29276-29277 29281 29283 29285 29299 29305 29312 29348-29349 29356 29392 29440-29441 29443-29444 29447 29464-29465 29468 29512-29513 29515-29518 29524-29525 29527 29532-29533 29539-29540 29542-29546 29548-29549 29552-29553 29565-29566 29686 29864 29867 29885 29914-29915 29928 30029 30038 30040 30210 30216 30218 30222-30223 30230 30237 30242-30245 30247 30260 30263-30265 30268 30288 30310 30312-30313 30315-30317 30319 30360 30381 30383 30401 30404 30418 30427 30519 30545 30641 30643-30645 31057-31058 31112 31399 31404-31405 31411 31416-31418 31577 31579-31580 31601 31603-31605 31706 32097 32447 32674 32680 32852 32894 32956 32959 33002 33026 33047-33048 33050-33051 33061 33063 33084-33085 33092 33094-33095 33104 33106-33107 33128-33130 33132-33133 33136-33137 33139 33141 33143 33148 33159 33230 33281 33285 33294-33295 33298-33299 33304 33317 33322 33435 33457 33796 33798-33799 33801-33804 33811 33814 33824-33826 33835 34242 35549 35714 35720 36651 36883 37006 37202 37333 37335 37343 37379 37383 37385 37410 37416 37418 37422 37440 37505 37508 37510 37514-37515 37518 37542-37543 37548-37550 37680 37846 37852 37884 37886-37887 37904 37921-37926 38016-38018 38026 38465 38522 38532 38912-38913 38916 38919 38922 38927 38930 39100 39241 39373 41589 41597 41653 41655 41682 41696 41772 42073 42207 42228-42229 42241 42271 42302 42314 42354-42355 42360-42361 42363 42378 42387 42389-42391 42393 42395-42396 42398 42400 42416-42417 42420 42433-42435 42439-42440 42444-42445 42450 42456 42470 42473 42476-42478 42485 42493 42495 42571 42837 42859 42875-42876 42879 42893 42907 42939 42959 42977 42980-42981 42988 42994 42996 43015 43017 43023 43227 43282 44308 44310 44360 44377 44379 45002 46846-46847 47742 47828 47852 47871 48028 48045 48058 48111 48212 48439https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/942/22?format=asciiInfrareddefaultJ/ApJ/942/22/table2Line measurements for APOGEE DR17 Br11 emittersSimbadNameSimbad column added by the CDSmeta.idcharnullablePlate[4914/12834] SDSS Plate IDmeta.id;instr.plateintMJD[55807/59234] Modified Julian Date of SDSS observation (JD-2400000.5)dtime.epochintFiber[1/300] SDSS Fiber IDmeta.idintRAJ2000Right Ascension, APOGEE DR17 (J2000)degpos.eq.ra;meta.mainDEJ2000[-85/86] Declination, APOGEE DR17 (J2000)degpos.eq.dec;meta.mainTelSDSS Telescope IDmeta.id;instr.telcharLoc[-999/7251] SDSS Location IDobs.fieldintFieldSDSS Field IDmeta.id;obs.fieldcharEWBr11-auto[0.75/27.4] Brackett 11 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloate_EWBr11-auto[0/24] Uncertainty in EWBr110.1nmstat.error;spect.line.eqWidthfloatEWBr12-auto[0.38/36.08]? Brackett 12 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr12-auto[0.05/20]? Uncertainty in EWBr120.1nmstat.error;spect.line.eqWidthfloatnullableEWBr13-auto[-1.62/21]? Brackett 13 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr13-auto[0.05/9]? Uncertainty in EWBr130.1nmstat.error;spect.line.eqWidthfloatnullableEWBr14-auto[-2.6/26.23]? Brackett 14 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr14-auto[0.05/16]? Uncertainty in EWBr140.1nmstat.error;spect.line.eqWidthfloatnullableEWBr15-auto[-2.3/21]? Brackett 15 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr15-auto[0.06/8.5]? Uncertainty in EWBr150.1nmstat.error;spect.line.eqWidthfloatnullableEWBr16-auto[-3.3/17.5]? Brackett 16 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr16-auto[0.06/17.1]? Uncertainty in EWBr160.1nmstat.error;spect.line.eqWidthfloatnullableEWBr17-auto[-0.96/21]? Brackett 17 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr17-auto[0.06/10.3]? Uncertainty in EWBr170.1nmstat.error;spect.line.eqWidthfloatnullableEWBr18-auto[-2.2/14.4]? Brackett 18 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr18-auto[0.07/10]? Uncertainty in EWBr180.1nmstat.error;spect.line.eqWidthfloatnullableEWBr19-auto[-5.71/10.6]? Brackett 19 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr19-auto[0.07/10]? Uncertainty in EWBr190.1nmstat.error;spect.line.eqWidthfloatnullableEWBr20-auto[-3.5/10.3]? Brackett 20 Scripted Equivalent width, Angstroms0.1nmspect.line.eqWidthfloatnullablee_EWBr20-auto[0.07/14]? Uncertainty in EWBr200.1nmstat.error;spect.line.eqWidthfloatnullableYCFlag[0/1] 1=Source is in the Young Cluster samplemeta.codeintYCEdens[8/12.4]? Electron Density of Best Fit Model to Brackett Decrement (1)cm**-3phys.density;meta.modelledfloatnullableB_YCEdens[10.4/12.4]? Maximum Electron Density (1)cm**-3phys.density;stat.maxfloatnullableb_YCEdens[8/12.2]? Minimum Electron Density (1)cm**-3phys.density;stat.minfloatnullablee_YCEdens[0.08/1.7]? Standard Deviation of Electron Densities (1)cm**-3stat.errorfloatnullableYCGasT[3750/15000]? Gas Temperature of Best Fit Model to Brackett Decrement (1)Kphys.temperatureintnullableB_YCGasT[12500/15000]? Maximum Gas Temperature (1)Kphys.temperature;stat.maxintnullableb_YCGasT[3750/10000]? Maximum Gas Temperature (1)Kphys.temperature;stat.maxintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintchisq[0/104]? Chi Square of Best Fit Model to Brackett Decrement (1)stat.fit.chi2;stat.param;meta.modelledfloatnullablem_IDNumber of SDSS spectra for this sourcemeta.numberintnullableFeII[0/3] FeII emission flag (3)meta.codeinte_YCGasT[1768/4086]? Standard Deviation of Gas Temperature (1)Kstat.errorintnullablee_chisq[2.3]? Standard Deviation of Chi Square values for fits (1)stat.errorfloatnullableslope[-0.9/4.1] Ratio of continuum fluxes near the Br 11 and Br 20 lines (2)phot.flux;arith.ratiofloatNN-Det[0/1] Neural Net Classification, Br Line Detection (1=line detected; 0=no line detected)meta.codeintNN-Dble[0/1] Neural Net Classification, Br Line Profiles (1=double peaked profile; 0=single peak profile)meta.codeintNN-Neb[0/1] Neural Net Classification, Br Line Width (1=narrow/ISM width; 0=Doppler broadened profile)meta.codeintNN-Good[0/1] Neural Net Classification, Br Line Quality (1=Good; 0=Bad)meta.codeintRVelBr-NN[-176/297]? Neural Net Estimate, Br Line Center Velocitieskm/sphys.velocfloatnullablee_RVelBr-NN[1.4/100]? Neural Net Estimate, Uncertainty in Br Line Center Velocitieskm/sstat.errorfloatnullableDVBr-NN[90/1332]? Neural Net Estimate, Velocity Width of Br Line Profileskm/sspect.line.widthfloatnullablee_DVBr-NN[1/354]? Neural Net Estimate, Uncertainty in Br Line Velocity Widthkm/sstat.errorfloatnullableMaxBr[11/20]? Highest order Brackett line detected by the Neural Net analysismeta.numberintnullableEWBr11-nn[0.14/84.55] Brackett 11 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr11-nn[0/53] Uncertainty in EWBr110.1nmstat.error;spect.line.eqWidthfloatEWBr12-nn[0.27/225] Brackett 12 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr12-nn[0/27.2] Uncertainty in EWBr120.1nmstat.error;spect.line.eqWidthfloatEWBr13-nn[0.13/121.3] Brackett 13 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr13-nn[0/18] Uncertainty in EWBr130.1nmstat.error;spect.line.eqWidthfloatEWBr14-nn[0.2/116] Brackett 14 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr14-nn[0/22.1] Uncertainty in EWBr140.1nmstat.error;spect.line.eqWidthfloatEWBr15-nn[0.14/57.5] Brackett 15 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr15-nn[0/15.2] Uncertainty in EWBr150.1nmstat.error;spect.line.eqWidthfloatEWBr16-nn[0.14/223.5] Brackett 16 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr16-nn[0/19.4] Uncertainty in EWBr160.1nmstat.error;spect.line.eqWidthfloatEWBr17-nn[0.14/37.5] Brackett 17 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr17-nn[0/14] Uncertainty in EWBr170.1nmstat.error;spect.line.eqWidthfloatEWBr18-nn[0/156] Brackett 18 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr18-nn[0/46.5] Uncertainty in EWBr180.1nmstat.error;spect.line.eqWidthfloatEWBr19-nn[0/73] Brackett 19 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr19-nn[0/19.5] Uncertainty in EWBr190.1nmstat.error;spect.line.eqWidthfloatEWBr20-nn[0/96] Brackett 20 Neural Net Equivalent width, Angstroms0.1nmspect.line.eqWidth;src.netfloate_EWBr20-nn[0/20] Uncertainty in EWBr200.1nmstat.error;spect.line.eqWidthfloat2MDisplay the 2MASS data (II/246) within 3"meta.ref.urlcharID2MASS Position-based Identifier ("2M" or "AP" HHMMSSss+DDMMSSs; J2000)meta.id;meta.mainchar