the radio/x-ray connection in young stellar objects in the orion nebula cluster
DESCRIPTION
The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster. By Scott J. Wolk and Jan Forbrich. Güdel (2002). Classes of Young Stellar Objects (YSOs). “class 0”. “class I”. Greene (2001). “class II”. “class III”. Lada (1987) André et al. (2000). ( (thermal) X-rays, - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/1.jpg)
By Scott J. Wolk and Jan Forbrich
![Page 2: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/2.jpg)
Güdel (2002)
![Page 3: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/3.jpg)
Classes of Young Stellar Objects (YSOs)
Greene (2001)
“class 0” “class I”
“class II” “class III”
Lada (1987)André et al. (2000)
![Page 4: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/4.jpg)
Feigelson & M
ontmerle (1999)
thermal radio((thermal) X-rays,nonthermal radio
X-rays and nonthermal radio emission probe the innermost regions of protostars,but currently only radio observations offer high angular resolution (VLBI).
NA
SA/C
XC
/M.W
eiss
Different fromother active stars (?)
![Page 5: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/5.jpg)
Feigelson & M
ontmerle (1999)
Thermal radio(e.g., free-free emission)
Nonthermal radio(e.g., gyrosynchrotronemission)
![Page 6: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/6.jpg)
Feigelson & M
ontmerle (1999)
...only~2 sources!
Thermal radio(e.g., free-free emission)
Nonthermal radio(e.g., gyrosynchrotronemission)
![Page 7: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/7.jpg)
Process: Gyrosynchrotron/non-thermal radiation
or Thermal free-free
GS identified by: Polarization, spectral index, rapid variability, high brightness
temperature
Problem (VLA): weak sources, measurement at single frequency
Best evidence for non-thermal radiation
requires high S/N – often not the case.
Difficult to constrain the emission processes of many weak sources.
YSO Radio Emission
![Page 8: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/8.jpg)
GMR A (Bower et al. 2003, Getman et al. 2003)
![Page 9: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/9.jpg)
European Southern Observatory
CrA: Optical image
![Page 10: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/10.jpg)
NA
SA/C
XC
/CfA
/J.Forbrich et al.
Forbrich & Preibisch (2007)
X-ray image
![Page 11: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/11.jpg)
NA
SA/C
XC
/CfA
/J.Forbrich et al.
X-ray image
![Page 12: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/12.jpg)
NA
SA/C
XC
/CfA
/J.Forbrich et al.
Forbrich et al. (2006, 2007)
X-ray image with radio data
~0.1 pc
![Page 13: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/13.jpg)
NA
SA/C
XC
/CfA
/J.Forbrich et al.
Forbrich et al. (2006, 2007)
X-ray image with radio data (offset)
~0.1 pc
![Page 14: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/14.jpg)
NGC 1333 & IC 348
~5% of YSOs have Simultaneous X-ray & radio detections
→ only three class I sources detected in X-rays and radio
NGC 1333: 2x 40 ksec Chandra + 22h VLA (X & C in subarrays)IC 348: 2x 40 ksec Chandra + 22h VLA (X & C in subarrays)
What about other clusters?
Forbrich, Osten & Wolk 2011
![Page 15: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/15.jpg)
What about other clusters?LkHα101 (Osten & Wolk 2009)
AGN
6 cm
LR (
1017
erg
s-1 H
z-1)
![Page 16: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/16.jpg)
All YSOs with Chandra and VLA detections (5 clusters)
Forbrich, Osten & Wolk 2011
![Page 17: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/17.jpg)
Zapata et al. 2004
![Page 18: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/18.jpg)
Zapata et al. 2004
![Page 19: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/19.jpg)
Results70 radio sources were detected in the primary VLA
field of the 3.6 cm observations rms noise ~0.05 mJy but high free-free background11 known class I/II YSOs
623 X-ray source in that field850 ks observation sensitive to log LX~27
Note: LX gives a rough estimate of stellar parameters
Only 46 detected in both.5 Class II YSOs1 Class I
![Page 20: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/20.jpg)
X-ray and Radio detection rates
![Page 21: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/21.jpg)
(Lack of) Impact of X-ray parameters on radio detection
![Page 22: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/22.jpg)
LX vs. LR diagram for the ONC
![Page 23: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/23.jpg)
What do we know?
We usually don’t see YSOs in the radio, but when we do they are over bright
We don’t know:Their YSO ClassRadio Spectrum
The radio signal is sometimes gyrosynchrotron GMR A, CRA IRS 5Other sources could be too, not enough S/NOptical depth could delay one of the signals
Could be thermal free-free Free-free should be bright.26/15 ARE proplydsBut most (109) proplyds are not detected and most
radio sources are not proplyds.
![Page 24: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/24.jpg)
VLA JVLA
Th
e N
ew
Yorke
r
![Page 25: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/25.jpg)
1. With Chandra and XMM-Newton, the number of X-ray detected YSOs has gone through the roof. Yet, the number of radio-detected YSOs has barely changed.
2. Observations (simultaneous) of the ONC, (NGC 1333, Lk H101, CrA, Oph and IC 348) are limited by the radio sensitivity; only a very low detection fraction of YSOs in both bands is found.
3. The NRAO Very Large Array is history – it is right now being transformed into the Jansky Very Large Array, a very different instrument (much better to prove the kind of emission!).
Conclusions
![Page 26: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/26.jpg)
![Page 27: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/27.jpg)
NGC 1333 & IC 348
NGC 1333: 2x 40 ksec Chandra + 22h VLA (X & C in subarrays)IC 348: 2x 40 ksec Chandra + 22h VLA (X & C in subarrays)
![Page 28: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/28.jpg)
NGC 1333 & IC 348
Class I sources (Gutermuth et al. 2008, Muench et al. 2007)
![Page 29: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/29.jpg)
What about other clusters?
ρ Oph (Gagné et al. 2004), LkHα101 (Osten & Wolk 2009)
Class I protostars first detected in X-rays and radio in CrA.→ try even more prominent (and compact) star-forming regions
IC 348NGC 1333
![Page 30: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/30.jpg)
Developments since 1999
1) With Chandra and XMM-Newton, the number of X-ray detected YSOs has gone through the roof. Yet, the number of radio-detectedYSOs has barely changed.
2) The (still growing) legacy of the Spitzer Space Telescope has provided us with a consistent roadmap to look for YSOs. We nowKnow much better where to look.
3) The NRAO Very Large Array is history – it is right now beingtransformed into the Expanded Very Large Array, a very differentinstrument.
![Page 31: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/31.jpg)
All Class I sources in VLA FOV
![Page 32: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/32.jpg)
All Class I sources in VLA FOV
α = 0.25
α < -0.78
α > 0.15
(?)
![Page 33: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/33.jpg)
NA
SA/C
XC
/CfA
/J.Forbrich et al.
X-ray image
![Page 34: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/34.jpg)
![Page 35: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/35.jpg)
![Page 36: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/36.jpg)
Feigelson & M
ontmerle (1999)
![Page 37: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/37.jpg)
EVLA Observations1) 2 Ghz vs. 100 MHz
2) 24 hours within one week
3)
![Page 38: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/38.jpg)
European Southern Observatory
CrA: Optical image
![Page 39: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/39.jpg)
Mid-infrared image
NA
SA/C
XC
/CfA
/IRA
C G
TO Team
![Page 40: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/40.jpg)
![Page 41: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/41.jpg)
![Page 42: The Radio/X-ray Connection in Young Stellar Objects in the Orion Nebula Cluster](https://reader038.vdocuments.net/reader038/viewer/2022110102/568140c5550346895dac8e57/html5/thumbnails/42.jpg)