J/A+A/565/A127ivo://CDS.VizieR/J/A+A/565/A127doi:10.26093/cds/vizier.35650127CDSDesmurs J.F.Bujarrabal V.Lindqvist M.Alcolea J.Soria-Ruiz R.,Bergman P.2017-06-02T08:37:20Z2014-05-27T11:02:20ZCDS support team

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

cds-question@unistra.frlate-type-starsinterstellar-masersinterferometryradio-astronomyThe v=1 and 2 J=1-0 (43GHz), and v=1 J=2-1 (86GHz) SiO masers are intense in AGB stars and have been mapped using VLBI showing ring-like distributions. Those of the v=1, 2 J=1-0 masers are similar, but the spots are rarely coincident, while the v=1 J=2-1 maser arises from a well separated region farther out. These relative locations can be explained by models including the overlap of two IR lines of SiO and H_2_O. The v=3 J=1-0 line is not directly affected by any line overlap and its spot structure and position, relative to the other lines, will be a good test to the standard pumping models The aims is to gain insight into the properties of the different SiO masers and the general theoretical considerations that can help to understand them. We present single-dish and VLBI simultaneous observations of the v=1, 2, 3 J=1-0 maser transitions of ^28^SiO in several AGB stars. The results are compared with the predictions of radiative models of SiO masers both including and not including the effect of IR line overlap. The spatial distribution of the SiO maser emission in the v=3 J=1-0 transition from AGB stars is systematically composed of a series of spots occupying a ring-like structure (as often found in SiO masers). The overall ring structure is extremely similar to that found in the other 43 GHz transitions, and very different from the structure of the v=1 J=2-1 maser. The positions of the individual spots of the different 43 GHz lines are however very rarely coincident, being in general separated by about 0.3AU (between 1 and 5mas). These results are very difficult to reconcile with standard pumping models, which predict the masers of rotational transitions within a given vibrational state to require very similar excitation conditions (since the levels are placed practically at the same energy from the ground), while the transitions of different vibrational states (which are separated by an energy of 1800K) should appear in different positions. However, models including line overlap tend to predict v=1, 2, 3 J=1-0 population inversion to occur under very similar conditions, while the requirements for v=1 J=2-1 appears clearly different, and are compatible with the observational results.2014A&A...565A.127Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/565/A127CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/565/A127https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/565/A127http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/565/A127https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/565/A127https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/565/A127http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/565/A127GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/565/A127/maps (List of fits maps)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/565/A127/maps?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/565/A127/maps?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/565/A127/maps?GETtext/xml+votable180.050000true58.3701711.406280.005555555555555556Cone search capability for table J/A+A/565/A127/table3 (Monitoring flux intensity in lines v=1,2,3)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/565/A127/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/565/A127/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/565/A127/table3?GETtext/xml+votable180.050000true16.608266712.59806940.0055555555555555566/1986 2500 2990 4355 4614 5647 7919 8532 9258 13813 14457 15650 17716 18364 23471 24151 29817 30087 30606https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/565/A127?format=asciiRadiodefaultJ/A+A/565/A127/mapsList of fits mapsNx[1024] Number of pixels along X-axismeta.numberintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainScale[0.0001] Scale of the imagearcsec/pixinstr.scalefloatNy[1024] Number of pixels along Y-axismeta.numberintFreq[42.51/43.12] FrequencyGHzem.freqfloatsize[4129/4224] Size of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file in subdirectory mapsmeta.id;meta.fitscharTitleTitle of the filemeta.notecharJ/A+A/565/A127/table3Monitoring flux intensity in lines v=1,2,3n_Fp5[*] closest to VLBA observation (1)meta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of AGB starmeta.id;meta.maincharLineLine (v1, v2 or v3)meta.id;spect.linecharNov08plot of spectrum observed on 2008-12-12meta.ref.urlcharl_Fp1Limit flag on Fp1meta.code.errorcharFp1? Peak flux observed on 2008/12/12Jyphot.fluxfloatnullableMar09plot of spectrum observed on 2009-03-17meta.ref.urlcharl_Fp2Limit flag on Fp2meta.code.errorcharFp2? Peak flux observed on 2009/03/17Jyphot.fluxfloatnullableAug09plot of spectrum observed on 2009-08-13meta.ref.urlcharl_Fp3Limit flag on Fp3meta.code.errorcharFp3Peak flux observed on 2009/08/13Jyphot.fluxfloatNov09plot of spectrum observed on 2009-11-07meta.ref.urlcharl_Fp4Limit flag on Fp4meta.code.errorcharFp4Peak flux observed on 2009/11/07Jyphot.fluxfloatn_Fp4[*] closest to VLBA observation (1)meta.notecharJan10plot of spectrum observed on 2010-01-08meta.ref.urlcharl_Fp5Limit flag on Fp5meta.code.errorcharFp5Peak flux observed on 2010/01/08Jyphot.fluxfloatDec10plot of spectrum observed on 2010-12-06meta.ref.urlcharl_Fp6Limit flag on Fp6meta.code.errorcharFp6Peak flux observed on 2010/12/06Jyphot.fluxfloatMar11plot of spectrum observed on 2011-03-06meta.ref.urlcharl_Fp7Limit flag on Fp7meta.code.errorcharFp7Peak flux observed on 2011/03/06Jyphot.fluxfloatApr11plot of spectrum observed on 2011-04-22meta.ref.urlcharl_Fp8Limit flag on Fp8meta.code.errorcharFp8Peak flux observed on 2011/04/22Jyphot.fluxfloatn_Fp8[*] closest to VLBA observation (1)meta.notecharMay11plot of spectrum observed on 2011-05-18meta.ref.urlcharl_Fp9Limit flag on Fp9meta.code.errorcharFp9Peak flux observed on 2011/05/18Jyphot.fluxfloatJun11plot of spectrum observed on 2011-06-15meta.ref.urlcharl_Fp10Limit flag on Fp10meta.code.errorcharFp10Peak flux observed on 2011/06/15Jyphot.fluxfloatOct11plot of spectrum observed on 2011-10-30meta.ref.urlcharl_Fp11Limit flag on Fp11meta.code.errorcharFp11Peak flux observed on 2011/10/30Jyphot.fluxfloatn_Fp11[*] closest to VLBA observation (1)meta.notecharDec11plot of spectrum observed on 2011-12-09meta.ref.urlcharl_Fp12Limit flag on Fp12meta.code.errorcharFp12Peak flux observed on 2011/12/09Jyphot.fluxfloatSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main