X-Ray Jets from Young Stars Manuel Güdel University of Vienna
HH34 HH111 Herbig-Haro Objects 100-400 Outline km s -1 • Herbig-Haro Objects • Inner Jets Manuel Güdel ETH Zürich • Cooling Protostar Switzerland • Heating Manuel Güdel (University of Vienna), Barbara Ercolano (Munich, Germany), • Conclusions James Owen (Cambridge, UK) (ESO) (Reipurth/HST/NASA) ESA
NeII X-Rays from Shocks against ISM Young Stellar Objects and their Impact on the Shock temperature Stellar Environment (Raga et al. 2002) requires a few 100 km s -1 : OK Luminosity for radiative or non-radiative shock: Manuel Güdel ETH Zürich Switzerland (Raga et al. 2002) typically works OK (L X ≈ 10 29-31 erg s -1 ). Manuel Güdel (University of Vies Owen (Cambridge, UK)
HH 2 (Orion) : at bow shock of HH object, 10 6 K, L X ≈ 5x10 29 erg s -1 V shock = 200 km s -1 HST required for heating measured motion: 230 km s -1 (Pravdo et al. 2001)
HH210 (Orion) : T = 0.8 MK in fastest HH feature, L X ≈ 10 30 erg s -1 : V shock = 170-240 km s -1 required observed bow-shock velocity 133-425 km s -1 X-rays HST [SII] (Grosso et al. 2006)
HH 80/81 (from very luminous source) 1.5x10 6 K, L X ≈ 4.5x10 31 erg s -1 V shock = 320 km s -1 required some optical features are much faster (600-1400 km s -1 ) (Pravdo et al. 2004; opt X contours: HST H ) (HST; NASA/ESA)
X Cepheus A East & West: HH168 X 6.4x10 6 K, L X ≈ 1.7x10 30 erg s -1 H X- rays behind Hα: cooling post-shock gas? V shock = 280-680 km s -1 sufficient ~consistent with optical line width in some places (200-600 km s -1 ) (Pravdo et al. 2005, Schneider et al. 2009)
[OI] (Dougados et al. 2000) DG Tau X-Rays (Güdel et al. 2005/08)) X-rays located close to jet base: Internal shocks, or collimation shocks? 5” L1551 IRS5, binary protostar (Favata et al. 2002, Bally et al. 2003)
Jet Base? L1551 IRS 5 Star absorbed, inner jet X-ray strong • Cooling jet due to expansion • standing structure at 0.5- 1” (Schneider+ 2011)
3 spectra over 1 week Spectroscopic X-Ray Jets DG Tau hard/hot: soft/cool: variable constant hard/hot high N H low N H >> N H (A V ) ? (Güdel et al. 2010) Coronal (hard) emission absorbed by dust-depleted accretion flows with N H > 10 22 cm -2
Extreme case: edge-on Sz 102 Spectrum very soft, T = 2.1 MK star absorbed, see only jet? ESA
0.3” Chandra ACIS-S image, soft band (0.3-1.5 keV) T = 1.8-3.3 MK v shock = 350-470 km s -1
Deconvolution of SER-treated ACIS data (Güdel+ 2012) 1pixel = 0.0615” 0.15” (33 AU along jet) 2-8 keV 0.3-1.5 keV T = 3.8 MK v shock = 500 km s -1 Offset in 2010 approx. identical to 2005/06 (Schneider et al.: POSTER P47): standing structure; collimation region!
Complete picture of DG Tau X-ray jet
filling factor f Radiative Cooling V DG Tau: EM = 1.39x10 52 cm -3 f = 3.5x10 -5 V = 1.77x10 43 cm -3 n e = 4.8x10 6 cm -3 T = 3.7x10 6 K τ = 0.6 yr L X = 1.8x10 29 erg s -1 IRS 5: EM = 8.0x10 51 cm -3 f = 1.23x10 -5 V = 5x10 45 cm -3 n e = 3.6x10 5 cm -3 T = 7.0x10 6 K τ = 15 yr L X = 8.0x10 28 erg s -1
DG Tau 0.35” (Dougados et al. 2008) half opening angle for DG Tau ≈ 10 deg (Agra-Amboage+ 2011: possibly smaller)
initial radius: 0.1” Cooling of inner source including expansion half opening: 10 deg DG Tau Requirement: Cooling time ~0.6 yrs: n 0 > 10 6 cm -3
L1551 IRS5 (Schneider et al. 2011)
Pressure in the Plasma: Stationary Source (Lavalley-Fouquet et al. 2000) optical n ≈ 10 6 cm -3 T ≈ 10 4 K nT = 10 10 K cm -3 DG Tau X-ray n e = 4.8x10 6 cm -3 T ≈ 3.7 x10 6 K nT = 1.8x10 13 K cm -3 (Itoh et al. 2000) optical n ≈ 10 6 cm -3 T ≈ 10 4 K nT = 10 10 K cm -3 IRS 5 X-ray n e = 3.6x10 5 cm -3 T ≈ 7 x10 6 K nT = 2.5x10 12 K cm -3 Hot gas contributes to jet expansion if not located at surface of jet or confined by magnetic fields
Origin of X-Ray Sources X-ray shocks in collimation region X-ray scattering Colliding winds/jets from the two components (Bally et al. 2003) Rhodos, 10 July 2008
NeII X-Rays from Shocks Young Stellar Objects and their Impact on the For high-T plasma close to star (L1551 IRS5, DG Tau) Stellar Environment measured shock speeds 50-100 km/s (Agra-Amboage et al. 2009, Lavalley-Fouquet et al. 2000) Even bulk flow speeds often < 300 km s -1 But then, shock temperatures Manuel Güdel ETH Zürich Switzerland (Raga et al. 2002) too low. Manuel Güdel (University of Vies Owen (Cambridge, UK)
Plasma Mass Loss Rate A DG Tau: radiative heating dominates in center d radiative decay time cooling distance emission measure v (Agra-Amboage+ 2011) Small amount of high-velocity gas that has escaped detection in the optical? (Günther et al. 2009)
NeII X-Rays from X-rays density Pulsed jets Young Stellar Objects • Periodically ejected blobs • Random velocity and their Impact on the Stellar Environment Collisions between blobs and environment: knots Depending on shocks, chains of X-ray knots especially in low-density jets Manuel Güdel mostly at jet base ETH Zürich Switzerland Higher ejection rate higher L X Manuel Güdel (University of Vienna), Barbara Ercolano (Munich, Germany), James Owen (Cambridge, UK) (Bonito et al. 2010)
density X-rays density Diamond shock at nozzle, 1500 km s -1 8 MK (Bonito et al. 2011 for L1551 IRS5)
Reconnection (Montmerle et al. 2000): Winding up star-disk fields Antiparallel fields Heating and Reconnection Ejection of hot plasmoids Further shock heating Jets? (Hayashi et al. 1996)
Photoevaporation by X-Ray Jets? Mass loss rate absorbed star from DG Tau disk jet dominated by jet irradiation at r > 22 AU X (Owen et al. in prep.) …although this wind does not compete with accretion: star: dM/dt ≈ 3x10 -10 M yr -1 jet: dM/dt ≈ 7x10 -10 M yr -1
HH OBJECTS: ç√ HH81 HH168-Cep A HH210 HH2 ç√ ç√ JETS: L1551 Z CMa DG Tau IRS5 HD 163296 OMC-3 RY Tau “SPECTROSCOPIC X - RAY JETS”: DG Tau GV Tau DP Tau HN Tau Beehive Sz 102
NeII Conclusions • X-rays found in protostellar and T Tauri jets from the base (collimation region?) to distant Herbig-Haro objects Manuel Güdel • Plasma close to stars: high densities in standing ETH Zürich structure Switzerland Manuel Güdel (University of Vienna), • Heating: shocks or magnetic? Barbara Ercolano (Munich, Germany), • Important influence on protoplanetary disks: James Owen (Cambridge, UK) heating, ionisation, chemistry, photoevaporation
NeII X-Rays from Young Stellar Objects and their Impact on the Stellar Environment END Manuel Güdel ETH Zürich Switzerland Manuel Güdel (University of Vienna), Barbara Ercolano (Munich, Germany), James Owen (Cambridge, UK) ESA
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