Stellar coronae and star formation with XEUS - sci.esa.intsci.esa.int/Conferences/xeus/26_Stars_with_XEUS_Stelze.pdf · Stellar coronae and star formation with XEUS ...

StellarcoronaeandstarformationwithXEUS

BeateStelzer(OAPalermo)

contributionsfromL.Scelsi,

S.Sciortino

Aquicktourofobservablesfrompre‐MStoMSages

AdaptedfromFeigelson&Montmerle,ARA&A,1999

X‐RAYSINCLASS0VERYCONTROVERSIAL

X‐RAYSINCLASSII(1)TRACEACCRETION(SHOCKS)(2)IONIZATIONAGENTOFDISK

X‐RAYSINCLASSIIIIDENTIFYLATEPre‐MSSTARS(CORONA)

X‐RAYSINMSCORONALSTRUCTURE

X‐RAYSINCLASSIJETS(SHOCKSINOUTFLOWS)

+X‐RAYSFROMHOTSTARS

+X‐RAYSFROMBROWNDWARFS

Need

moresensitivehighspatialresolutionhighspectralresolution

X‐rayobservations

CLASS0:X‐rays?Needhighsensitivity+highspatialresolution

Giardinoetal.(2007)

Co‐addedACISimagefrom6Class0intoeffective540ksexposure:

Assume:NH=41023cm‐2,kT=2.4keVLx<41029erg/s

Class0fainterX‐raysthanClassI,II,IIIorextremeextinction

Serpensstarformingregion:Spitzer/IRAC1imagewithChandra/ACISfield

XEUS/WFI:Llim~41029erg/sforNH=1024cm‐2

in~10ks@260pc

Protostellarandpre‐MSjets:Needhighspatialresolution+highsensitivity

LaValleyetal.(1997)

[OI]6300A

Smoothed Color‐coded

0.6‐1.7keVACIS‐S:DGTau+jets

Guedeletal.(2008)

4”

4X‐rayemittersinDGTausystem:

• soft,weaklyabsorbedjet• soft,strongerabsorbedcounterjet• soft,weaklyabsorbedbaseofforwardjet• hardstellarcorona

Guedeletal.(2008)

UnfeasiblewithXMM!



Guedeletal.(2008)

4”


4X‐rayemittersinDGTausystem:

• soft,weaklyabsorbedjet• soft,strongerabsorbedcounterjet• soft,weaklyabsorbedbaseofforwardjet• hardstellarcorona

Guedeletal.(2008)

Diskgas‐to‐dustratiofromdifferentialextinctionofjet+counterjetbut9countsfromcounter‐jetin90ksecChandra



Guedeletal.(2008)

4”


CLASSII:accretionvs.magneticactivityNeedhighspectralresolution+highsensitivity

• Diagnosticforaccretionshock:high‐density(~1012cm‐3)(vs.low‐densitycorona)

linediagnostics,He‐liketriplets

• fewcTTSbrightenoughforXMM/Chandragratings

TWHyaGuentheretal.(2007)

RGSNeIXtriplet(corona+shock)


Schmittetal.(2005)

130ksXMM/RGS

lowf/iratiohighdensity:31011cm‐3

(notconsideringUVradiationandcoronalcontribution)

100ksXEUS/TES


Schmittetal.(2005)

130ksXMM/RGS

lowf/iratiohighdensity:31011cm‐3

(notconsideringUVradiationandcoronalcontribution)

100ksXEUS/TES

Tripletsofhigh‐energyelementsrepresentcoronane=f(T)

HR9024(Ggiant)–Testietal.(2008)

6.4keVKα lineduringinitialphaseofflare

photosphericfluorescencemodelconstrainsflareheight:~0.1R*

FeKαemission:fluorescenceore‐impactionization?

Elias29(ClassIprotostarinOph)‐‐Giardinoetal.(2007):

6.4keVΚα lineinquiescentphaseafteraflare

sustainedionizationmechanismindependentofX‐rays;coll.Ionizationbynon‐thermalelectronsinstar‐diskloops

FeKFeXXV

HR9024(Ggiant)–Testietal.(2008)

6.4keVKα lineduringinitialphaseofflare

photosphericfluorescencemodelconstrainsflareheight:~0.1R*

FeKαemission:fluorescenceore‐impactionization?

Elias29(ClassIprotostarinOph)‐‐Giardinoetal.(2007):

6.4keVΚα lineinquiescentphaseafteraflare

sustainedionizationmechanismindependentofX‐rays;coll.Ionizationbynon‐thermalelectronsinstar‐diskloops

FeKFeXXV

FeKemissionwithXEUS/WFI

Highsensitivity,highspectralresolution,largefield‐of‐view

detectionofFeKαinlargesampleofstarsindifferentevolutionphases

equiv.width>50Ådetectablein15ks(photosphere)

Constraingeometryby(A)modelingphotosphericfluorescenceefficiency(B)detectingtime‐delaybetweenflareandappearanceofFeKlinefordisk‐fluorescence

85ksXMM/pn 15ksXEUS/WFI

Giardinoetal.(2007)

W=250ÅFeKα

FeXXV

MSstars:CoronalmappingNeedhighsensitivity

Hussainetal.(2005)

RotationalmodulationofX‐rayemissiononnearbyflarestarABDorinhomogeneousdistributionofX‐rayemittingmaterial?

Prot~0.5d

MSstars:CoronalmappingNeedhighsensitivity

Hussainetal.(2007)

OVIII

=0.3 =0.8

spotmapExtrapolationofsurfacefieldtocoronamodelingofX‐rayemittingloopsreconstructionofX‐raylightcurve

RESULTS:nopolarityreversalbetweenthetwohemispheresforABDor

Flarephysics:plasmaevolutioninrisephaseNeedhighsensitivityfortime‐resolvedspectroscopy

Stelzeretal.(2006)

LP412‐31:simultaneousopt/X‐rayflarewithXMM

Fastopticalevent:V = 6 magin40sec

Δtopt./X‐raypeak<20sec

Time‐resolvedspectroscopy…HDmodelofflaredecayheating,looplengthFILLLONGLOOPINSHORTTIMEI.E.HIGHVELOCITY(LINESHIFT)

…inflarerise?

Flarephysics:plasmaevolutioninrisephaseNeedhighsensitivityfortime‐resolvedspectroscopy

Schmittetal.(2008)

Time‐resolvedspectroscopy…HDmodelofflaredecayheating,looplengthFILLLONGLOOPINSHORTTIMEI.E.HIGHVELOCITY(LINESHIFT)

…inflarerise?

PotentialofXEUSstellarstudies

• derivecompletePre‐MSpopulation(togetherwithIR)invariousenvironmentsIMF,diskfraction,…

• trace+distinguishhotplasmafromvariousphysicalprocesses:magneticactivity,accretionandwinds

• coronalstructure(fieldmapping,flareanalysis)

• roleofX‐raysforstarformationbyionizingcircumstellardisks+facilitatingaccretion

• X‐raysfromhotstarswindclumping,masslossrates,…

• X‐raysfrombrowndwarfsdynamosinsub‐stellarobjects

Hotstars:linebroadening(winds)Needhighspectralresolution+highsensitivity

Broad

Narrow

1kev2.5kev 0.48kev

XEUSBETTER(2eV)@EqualStatistics

Oskinovaetal.(2005)

Hotstars:linebroadening(winds)Needhighspectralresolution+highsensitivity

Cassinellietal.(2001)

(A)asymmetric,blue‐shiftedlines

highopticaldepth

Oskinovaetal.(2005)

(B)symmetric,lines

transparentwind

Hotstars:OriginofX‐rays?Needhighspectralresolution+highsensitivity

1 OriConlyhotstarwithrisingDEM

Wojdowski&Schulz(2005)

Gagneetal.(2005)

X‐raysfrommagn.Confinedwind

Weaklyabsorbed,softBDinONC

Lx=1027erg/s@450pc

fx=410‐17erg/cm2/s

(fx)abs=110‐17erg/cm2/[email protected]‐2keVforNH=21022cm‐2(Av=10mag)kT=1keVin100ksecwithXEUS

BrowndwarfswithXEUS

Preibischetal.(2005)

Stellar coronae and star formation with XEUS - sci.esa.intsci.esa.int/Conferences/xeus/26_Stars_with_XEUS_Stelze.pdf · Stellar coronae and star formation with XEUS ...

Documents