Chandra Emission Line Chandra Emission Line Diagnostics of Diagnostics of Sco Sco

Carolin N Cardamone Carolin N Cardamone

Advisor: David CohenAdvisor: David Cohen

What is the source of What is the source of the x-rays? the x-rays?

Coronal Heating Stellar Wind Shock Heating

This feature is resolved into individual emission lines by Chandra.

ROSAT

Chandra

ROSAT data from 1992-4 shows a broad emission feature near 1 keV.

Fe XVII lines in Tau ScoFe XVII lines in Tau Sco

A Comparison of A Comparison of the Ne X line in the Ne X line in

Sco to Capella and Sco to Capella and Zeta Pup.Zeta Pup.

Broad emission lines (large FWHM) are indicative of winds

flowing outward from the star.

Capella (Coronal) Zeta Pup (Wind?)

Line widths indicate Line widths indicate velocities.velocities.

FWHM of lines across 7 stars

-400-200

0200400600800

10001200

1 2 3 4 5 6 7

FW

HM

(k

m/s

)

Capella Sco Pup Ori Ori OriAB DorNe X (12.13), Fe XVII (15.01), O VIII (18.97)

Cool Stars(Coronal)

Hot Stars(Wind)

Occultation by the star blocks the back (red) side of the wind.

We would expect to see mostly blue shifted winds.

To earth

Line centers indicate bulk Line centers indicate bulk motions.motions.

ROSAT

Central shifts in Velocity Units.

-200

-100

0

100

200

0 20 40 60

Atomic Weight

Wav

elen

gth

Sh

ift

(Km

/s)

The line centers are red-The line centers are red-shifted.shifted.

This is a plot of the strongest lines in Sco.

ROSAT

Conclusions:Conclusions:

Line broadening more than thermal Line broadening more than thermal seen from coronal sources, less than seen from coronal sources, less than expected from wind shock. expected from wind shock.

Blob infall model (Red-shifted Blob infall model (Red-shifted wavelengths) wavelengths)

Hybrid form of wind shock and Hybrid form of wind shock and coronal?coronal?

Several Strong lines in Tau ScoSeveral Strong lines in Tau Sco

Star Name FWHM uncertainty Velocity (km/s) uncertaintyCapella 0.0003 0.0002 3.26 2.23Tau Sco 0.0187 0.0017 231.82 21.02Zeta Pup 0.0574 0.0030 709.45 37.10Zeta Ori 0.0661 0.0040 816.89 49.46Delta Ori 0.0441 0.0049 545.60 60.59Theta Ori 0.0346 0.0033 427.56 40.81

Data from the lines of Tau Data from the lines of Tau ScoScoelement pos error fwhm error ampl error

atomic weight

Velocity (Km/s) uncertainty Temp uncertainty

predicted fwhm uncertainty Data sets used

S XV 5.068 0.0060 0.0680 0.0116 0.000023 0.000004 28.09 2013 343 98,675,675 16,795,189 0.022 0.0001 9, 10Si XIV 6.182 0.0007 0.0121 0.0021 0.000019 0.000002 28.09 294 50 2,099,390 357,011 0.026 0.0000 3, 4, 9,10Si XIII 6.650 0.0005 0.0099 0.0016 0.000032 0.000002 28.09 223 35 1,212,251 191,441 0.028 0.0000 3,4,9,10Si XIII 6.689 0.0011 0.0104 0.0036 0.000010 0.000001 28.09 234 81 1,333,083 459,970 0.029 0.0000 3, 4, 9,10Si XIII 6.740 0.0005 0.0065 0.0032 0.000021 0.000002 28.09 144 71 507,497 250,330 0.029 0.0000 3,4,9,10Mg XII 8.423 0.0006 0.0114 0.0024 0.000028 0.000002 24.31 203 43 866,414 182,614 0.039 0.0000 3, 4, 9,10,109,110MgXI 9.173 0.0009 0.0172 0.0025 0.000041 0.000003 24.31 282 41 1,674,870 245,054 0.042 0.0000 9, 10MgXI 9.233 0.0011 0.0122 0.0048 0.000022 0.000002 24.31 198 78 823,400 324,813 0.042 0.0000 9, 10Ne X 10.239 0.0016 0.0180 0.0047 0.000020 0.000002 20.97 264 69 1,264,794 330,197 0.051 0.0000 9, 10Ne X 12.134 0.0005 0.0218 0.0013 0.000183 0.000007 20.97 270 16 1,324,574 76,175 0.060 0.0000 3, 4, 9,10,109,110FVII 12.275 0.0013 0.0293 0.0030 0.000076 0.000006 19.00 358 36 2,109,364 214,769 0.064 0.0000 9, 10Fe XX 12.834 0.0020 0.0350 0.0044 0.000061 0.000006 19.00 409 52 2,757,966 348,169 0.067 0.0000 9, 10Fe XVII 15.016 na 0.0001 0.0299 0.000258 0.000014 55.85 1 na 51 na 0.045 na 3, 4, 9, 10,109,110OVIII 16.005 0.0002 0.0007 0.0012 0.000118 0.000010 16.00 6 11 538 949 0.091 0.0000 9, 10, 109FeXVIII 16.075 na 0.0008 0.0411 0.000072 0.000008 16.00 7 na 732 na 0.091 na 9, 10, 109Fe XVII 16.776 0.0041 0.0012 0.0012 0.000221 0.000013 55.85 11 11 5,446 5,510 0.051 0.0000 9, 10, 109, 110Fe XVII 17.054 0.0008 0.0241 0.0021 0.000293 0.000015 55.85 212 18 2,178,085 185,172 0.052 0.0000 9, 10, 109Fe XVII 17.099 0.0006 0.0145 0.0022 0.000266 0.000015 55.85 127 19 781,062 118,684 0.052 0.0000 9, 10, 109OVIII 18.970 0.0010 0.0381 0.0023 0.000516 0.000026 16.00 301 18 1,257,964 76,394 0.107 0.0000 9, 10, 109, 110O VII 21.603 0.0026 0.0374 0.0062 0.000200 0.000027 16.00 259 43 933,964 155,893 0.122 0.0000 9, 10O VII 21.809 0.0017 0.0236 0.0048 0.000265 0.000031 16.00 163 33 366,937 74,849 0.123 0.0000 9, 10N VII 24.783 0.0033 0.0438 0.0074 0.000202 0.000042 14.01 265 45 854,498 145,198 0.150 0.0000 9

These are the calculated best-fit values found from fitting a Normalized Gaussian plus a Polynomial.

Velocities correspond to the half width of the lines

This is the temperature required to give the observed width of the line. It assumes width is due entirely to thermal braodening.

The predicted fwhm corresponds to the fwhm predicted from a temperature of 10 million degress. Again this assumes width due to thermal broadening.

This Amplitude is the total integrated number of counts under the lines, i.e. it is proportional to the line flux.

htatomicweigApos

cfwhmTemp

2

2ln58.2

Width vs Wavelength

0.000.020.040.060.08

0 5 10 15 20 25 30Wavelength

FW

HM

ROSATNe X from Tau Sco Overplotted on Capella

Tau Sco is slightly wider.