J/ApJ/843/31ivo://CDS.VizieR/J/ApJ/843/31doi:10.26093/cds/vizier.18430031CDSYoungblood A.France K.Loyd R.O.P.Brown A.Mason J.P.Schneider P.C.,Tilley M.A.Berta-Thompson Z.K.Buccino A.Froning C.S.Hawley S.L.,Linsky J.Mauas P.J.D.Redfield S.Kowalski A.Miguel Y.Newton E.R.,Rugheimer S.Segura A.Roberge A.Vieytes M.2018-05-16T07:02:04Z2018-03-20T15:16:35ZCDS support team

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

cds-question@unistra.frm-starsspectroscopyultraviolet-astronomyvisible-astronomyline-intensitiesCharacterizing the UV spectral energy distribution (SED) of an exoplanet host star is critically important for assessing its planet's potential habitability, particularly for M dwarfs, as they are prime targets for current and near-term exoplanet characterization efforts and atmospheric models predict that their UV radiation can produce photochemistry on habitable zone planets different from that on Earth. To derive ground-based proxies for UV emission for use when Hubble Space Telescope (HST) observations are unavailable, we have assembled a sample of 15 early to mid-M dwarfs observed by HST and compared their nonsimultaneous UV and optical spectra. We find that the equivalent width of the chromospheric Ca II K line at 3933{AA}, when corrected for spectral type, can be used to estimate the stellar surface flux in ultraviolet emission lines, including HI Ly{alpha}. In addition, we address another potential driver of habitability: energetic particle fluxes associated with flares. We present a new technique for estimating soft X-ray and >10MeV proton flux during far-UV emission line flares (Si IV and He II) by assuming solar-like energy partitions. We analyze several flares from the M4 dwarf GJ 876 observed with HST and Chandra as part of the MUSCLES Treasury Survey and find that habitable zone planets orbiting GJ 876 are impacted by large Carrington-like flares with peak soft X-ray fluxes >=10^-3^W/m^2^ and possible proton fluxes ~10^2^-10^3^pfu, approximately four orders of magnitude more frequently than modern-day Earth.2017ApJ...843...31Yhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/843/31CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIII/198 : Palomar/MSU nearby star spectroscopic survey (Hawley+ 1997)I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)J/A+AS/125/149 : CHIANTI - Atomic Database For Emission Lines I. (Dere+ 1997)J/A+A/326/249 : Chromospheric models of dwarf M stars (Mauas+ 1997)J/A+A/414/699 : Spectra of southern late-type dwarfs (Cincunegui+, 2004)J/ApJ/634/625 : Radial velocities and photometry of GJ 876 (Rivera+, 2005)J/A+A/469/309 : Chromospheric activity in late-type stars (Cincunegui+, 2007)J/ApJ/736/12 : Transit light curves of GJ1214 (Berta+, 2011)J/ApJ/728/48 : Multicolor eclipse data for 6 new binaries (Kraus+, 2011)J/ApJ/761/166 : Terrestrial exoplanet atmospheres. I. (Hu+, 2012)J/AJ/143/134 : Cand. members of {beta} Pic / AB Dor groups (McCarthy+, 2012)J/ApJS/211/9 : Variability in UV line emission of F-M stars (Loyd+, 2014)J/AJ/148/64 : HAZMAT I. FUV & NUV emission in early M stars (Shkolnik+, 2014)J/ApJ/807/45 : Potentially habitable planets around M dwarfs (Dressing+, 2015)J/ApJ/812/3 : MEarth mid-to-late M dwarfs rotation & kinematics (West+, 2015)J/ApJ/822/97 : Rotation-Activity relations in K-M dwarfs. (Houdebine+, 2016)http://archive.stsci.edu/prepds/muscles/ : MUSCLES Treasury Survey on MASThttp://casa.colorado.edu/~ayres/StarCAT/ : HST STIS Echelle Spectral Cataloghttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/843/31https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/843/31http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/843/31https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/843/31https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/843/31http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/843/31GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/843/31/mdwarfs (UV emission line fluxes of the M dwarf (tables 2 and 3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/843/31/mdwarfs?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/843/31/mdwarfs?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/843/31/mdwarfs?GETtext/xml+votable180.050000true323.3915639-49.00900530.0055555555555555566/4444 13743 18496 22289 23735 24227 28548 31216 38464 41591 42459 44921 46632 48274 48926https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/843/31?format=asciiUVOpticaldefaultJ/ApJ/843/31/mdwarfsUV emission line fluxes of the M dwarf (tables 2 and 3)Rad[0.1/0.9] RadiussolRadphys.size.radiusfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqRunning number used in this papermeta.numberintNameStar namemeta.id;meta.maincharExo[*] *: stars with known exoplanetsmeta.codecharDist[1.3/14.6] Distancepcpos.distance;pos.heliocentricfloatr_Dist[a-e] Reference for Dist (1)meta.ref;pos.framecharr_RadReference(s) for Rad (1)meta.ref;pos.framecharSpTSpectral Typesrc.spTypecharr_SpTReference(s) for SpT (1)meta.ref;pos.framecharTeff[2820/3680] Effective temperature (2)Kphys.temperature.effectiveintr_TeffReference for Teff (1)meta.ref;pos.framecharl_ProtLimit flag on Protmeta.code.errorcharProt[2.2/132.5]? Rotational period (2)dtime.periodfloatnullabler_ProtReference for Prot (1)meta.ref;pos.framecharEWCaK[0.3/21.3] Equivalent Width, Ca II K line0.1nmspect.line.eqWidthfloate_EWCaK[0.01/6] Uncertainty in EWCaK0.1nmstat.errorfloatEWCaKc[0.04/11.5] Corrected EW Ca II K line0.1nmspect.line.eqWidthfloate_EWCaKc[0.005/2.1] Uncertainty in EWCaKc0.1nmstat.errorfloatInstSource(s) for EWCaK measurements (3)meta.id;instrcharNCaK[1/351] Number of Ca II K spectrameta.numberintRefFlux sources (4)meta.bibcharSiIII? SiIII emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_SiIII? Uncertainty in SiIIImW.m**-2stat.errordoublenullableLyA? LyA emission line flux, erg/cm^2^/s (5)mW.m**-2phot.flux;spect.linedoublenullablee_LyA? Uncertainty in LyA (5)mW.m**-2stat.errordoublenullableSiII? SiII emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_SiII? Uncertainty in SiIImW.m**-2stat.errordoublenullableCII? CII emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_CII? Uncertainty in CIImW.m**-2stat.errordoublenullableMgII? MgII emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_MgII? Uncertainty in MgIImW.m**-2stat.errordoublenullableSiIV? SiIV emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_SiIV? Uncertainty in SiIVmW.m**-2stat.errordoublenullableHeII? HeII emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_HeII? Uncertainty in HeIImW.m**-2stat.errordoublenullableCIV? CIV emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_CIV? Uncertainty in CIVmW.m**-2stat.errordoublenullableNV? NV emission line flux, erg/cm^2^/smW.m**-2phot.flux;spect.linedoublenullablee_NV? Uncertainty in NVmW.m**-2stat.errordoublenullableEUV? EUV flux, erg/cm^2^/s (6)mW.m**-2phot.fluxdoublenullableSimbadSimbad 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