Symbiotic Star CI Cygni
Spectroscopic Monitoring of the ongoing outburst

May 30 , 2011 update


The symbiotic star CI Cygni has undergone a new outburst (#ATEL 2732, U. Munari & al., 12 Jul 2010). This is the second of a new cycle of outbursts. The last cycle of outbursts (3 outbursts) occured in the 70'. An eclipse of the hot componant will occur during the rising phase of the ungoing outburst. The maximum of the eclipse is expected during november, 2010.
Coordinates (2000.0) : R.A. = 19h50m11s.83, Decl. = +35°41''03

This page gathers amateur spectroscopic results.
First results from this observing campaign : CI Cygni 2010 outburst and eclipse, JAAVSO, 2001 : http://www.aavso.org/ejaavso

The monitoring goes on in order to acquire spectra during quiescence, waiting for a possible third outburst. All observations - low to high resolution - are welcome
(send fit and/or dat files to : francois.teyssier-at-dbmail.com)


 

30-05-2011
Current magnitude = 10.8V
Current phase = 0.252
[1]
 

log of observations

line identification

spectral variations

line measurements

links

publications about CI Cygni
and bibliography

[1] Ephemeris : Min(V) = 2442690 + 853.8E
(A. Siviero & al., 2009)
Magnitude V from AAVSO database (JD-2450000) [*]
 

 


 

Log of observations

Obs. #

Date (DD/MM/YYYY)

Observer

Telescope

Exposure

Dispersion (nm/px)
Resolution
Range (nm)
fits files
dat files

notes

#01

30.917 / 06 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

6 x 600 s

0.428
600-700
433-720
_cicyg__cicyg_20100630_teyssier.fit

_cicyg_2010630_teyssier.dat

[1]

#02

24.893 / 07 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

6 x 600 s

0.428
600-700
427-720
_cicyg_20100724_teyssier.fit
_cicyg_20100724_teyssier.dat
*

#03

02.903 / 08 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

6 x 300 s

0.428
600-700
442-730
_cicyg_20100802_teyssier.fit

_cicyg_20100802_teyssier.dat*

*
#04

08.854 / 08 / 2010

Christian Buil

C9 0.23 m
LISA 300 l/mm

12 x 240 s

* *
390-730

* _cicyg_20100808_854.fit

_cicyg_20100808_854.dat
*

#05

09.034 / 08 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

6 x 600 s

0.428
600-700
423-716
_cicyg_20100809_teyssier.fit

_cicyg_20100809_teyssier.dat

*
#06

12.079 / 08 / 2010

Benjamin Mauclaire

Lhires III 2400 l/mm

9 x 600 s

*
*
652-669
ci_cyg_20100812_mauclaire.fit
*
*

#07

18.890 / 08 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

6 x 600 s

0.428
600-700
423-720
_cicyg_20100818_teyssier.fit

_cicyg_2010818_teyssier.dat

*

#08

23.830 / 08 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

5 x 300 s

0.428
600-700
423-720
_cicyg_20100823_teyssier.fit

_cicyg_20100823_teyssier.dat

*

#09

25.848 / 08 / 2010

Christian Buil

C9 0.23 m
eShel

12 x 600 s

0.012
11000
390-720
_cicyg_20100825_848.fit*

_cicyg_20100825_buil.dat

*
#10

30.833 / 08 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

9 x 300 s

0.428
600-700
440-720
_cicyg_20100830_teyssier.fit

_cicyg_20100830_teyssier.dat

*
#11

30.848 / 08 / 2010

Christian Buil

C9 0.23 m
eShel

12 x 600 s

0.012
11000
390-720

_cicyg_2100080_848.fit

_cicyg_21000830_848.dat  
#12

01.926 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

9 x 300 s

0.214
600-700
440-720
_cicyg_20100901_teyssier.fit
_cicyg_20100901_teyssier.dat
*
#13

03.843 / 09 / 2010

Christian Buil

C11 0.28 m
eShel

14 x 600 s

0.012
11000
390-720

_cicyg_21000903_843.fit

_cicyg_21000903_843.dat  
#14

03.905 / 09 / 2010

Benjamin Mauclaire

Lhires III 2400 l/mm

7 x 600 s

*
*
651-668
ci_cyg_20100903_905.fit
   
#15

04.940 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

4 x 600 s

0.214
600-700
420-718
_cicyg_20100904_teyssier.fit
_cicyg_20100904_teyssier.dat
 
#16

05.824 / 09 / 2010

Christian Buil

C11 0.28 m
eShel

12 x 600 s

0.012
11000
428-712
_cicyg_20100905_824.fit
_cicyg_20100905_824.dat
 
#17

08.830 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

5 x 600 s

0.214
600-700
423-718
cicyg_20100908_teyssier.fit
CICyg_20100908_teyssier.dat
 
#18

10.821 / 09 / 2010

Christian Buil

C11 0.28 m
eShel

12 x 600 s

0.012
11000
428-712
_cicyg_20100910_821.fit
_cicyg_20100910_821.dat
 
#19

10.835 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

4 x 600 s

0.214
600-700
423-716
cicyg_20100910_teyssier.fit
CICyg_20100910_teyssier.dat
 
#20

14.806 / 09 / 2010

Christian Buil

C11 0.28 m
eShel

14 x 600 s

0.012
11000
428-712
_cicyg_20100914_806.fit
_cicyg_20100914_806.dat
 
#21

17.883 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

6 x 600 s

0.214
600-700
423-716
cicyg 20100917_teyssier.fit
cicyg 20100917_teyssier.dat
 
#22

18.825 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

6 x 600 s

0.214
600-700
423-716
cicyg_20100918_teyssier.fit
CICyg_20100918_teyssier.dat
 
#23

21.836 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

7 x 300 s

0.418
600-700
472-717
_cicyg_20100921_teyssier.fit
_cicyg_20100921_teyssier.dat
 
#24

21.791 / 09 / 2010

Christian Buil

C11 0.28 m
eShel

14 x 600 s

0.012
11000
428-712
_cicyg_20100921_791.fit
_cicyg_20100921_791.dat
 
#25

22.889 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

8 x 300 s

0.418
600-700
423-716
_cicyg_20100922_teyssier.fit
_cicyg_20100922_teyssier.dat
 
#26

25.860 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

8 x 300 s

0.418
600-700
415-710
_cicyg_20100925_teyssier.fit
_cicyg_20100925_teyssier.dat  
#27

30.822 / 09 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

5 x 300 s

0.418
600-700
420-712
_cicyg_20100930_teyssier.fit
_cicyg_20100930_teyssier.dat
 
#28

7.825 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

11 x 300 s

0.418
600-700
421-712
_CICyg_20101007_825.fit
Fichiers/cicyg_20101007_825.dat
 
#29

9.817 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

11 x 300 s

0.418
600-700
420-712
_cicyg_20101012_825.fit
cicyg_20101012_teyssier.dat
 
#30

12.821 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

11 x 300 s

0.418
600-700
420-712
_cicyg_20101012_825.fit
Fichiers/cicyg_20101012_teyssier.dat
 
#31

14.784 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
_cicyg_20101014_784.fit
_cicyg_20101014_784.dat
 
#32

14.785 / 10 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
_ci_Cyg_20101014_785.fit
 
#33

15.767 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
_cicyg_20101015_767.fit
_cicyg_20101015_767.dat
 
#34

16.847 / 10 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

15 x 600 s

0.0168
15000
650-661
_ci_Cyg_20101016_847.fit
 
#35

17.801 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

16 x 300 s

0.418
600-700
420-710
_cicyg_20101017_801.fit
 
#36

18.766 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

5 x 600 s
0.012
11000
428-712
_cicyg_20101018_766.fit
_cicyg_20101018_766.dat
 
#37

19.754 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
_cicyg_20101019_754.fit
_cicyg_20101019_754.dat
 
#38

20.798 / 10 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

8 x 960 s

0.0168
15000
650-661
_ci_Cyg_20101020_798.fit
ci_cyg_20101020_798_tg.dat
 
#39

20.809 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

13 x 300 s

0.418
600-700
420-710
_CICyg_20101020.fit
 
#40

21.753 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
 
#41

22.778 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

15 x 300 s

0.418
600-700
420-710
fit
dat
 
#42

25.753 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
 
#43

25.771 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 300 s

0.418
600-700
420-710
fit
 
#44

26.747 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
fichier_dat
 
#45

26.800 / 10 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fichier_dat
 
#46

27.754 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
fichier_dat
 
#47

28.750 / 10 / 2010

Christian Buil

C11 0.28 m
eShel

8 x 600 s
0.012
11000
428-712
fichier_dat
 
#48

29.869 / 09 / 2010

Benjamin Mauclaire

Lhires III 2400 l/mm

5 x 600 s

*
*
651-668
low snr
#49

30.791 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 300 s

0.418
600-700
420-710
fichier_dat
 
#50

31.785 / 10 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 300 s

0.418
600-700
420-710
fichier_dat
 
#51

31.795 / 10 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#52

01.775 / 11 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 300 s

0.418
600-700
420-710
fichier_dat
 
#53

03.739 / 11 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#54

05.769 / 11 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#55

07.744 / 11 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 300 s

0.418
600-700
420-710
fichier_dat
 
#56

10.732 / 11 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#57

18.787 / 11 / 2010

Benjamin Mauclaire

Lhires III 2400 l/mm

14 x 600 s

*
*
652-669
fit
   
#58

20.755 / 11 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#59

20.773 / 11 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

8 x 600 s

0.418
600-700
440-710
fichier_dat
 
#60

24.713 / 11 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#61

26.813 / 11 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
651-661
fit
   
#62

03.790 / 12 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

16 x 300 s

0.418
600-700
440-710
fit
fichier_dat
 
#63

08.728 / 12 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

4 x 960 s

0.0168
15000
650-661
fit
   
#64

11.746 / 12 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#65

12.742 / 12 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 300 s

0.418
600-700
440-710
fit
fichier_dat
 
#66

13.715 / 12 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 200 s

0.418
600-700
440-710
fit
fichier_dat
 
#67

14.713 / 12 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

12 x 200 s

0.418
600-700
440-710
fit
fichier_dat
 
#68

25.750 / 12 / 2010

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

7 x 300 s

0.418
600-700
440-710
fit
fichier_dat
 
#69

26.751 / 12 / 2010

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

10 x 960 s

0.0168
15000
650-661
fit
   
#70

02.731 / 01 / 2011

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

7 x 300 s

0.418
600-700
fit
fichier_dat
 
#71

10.747 / 01 / 2011

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

6 x 960 s

0.0168
15000
650-661
fit
fichier_dat
 
#72

24.731 / 01 / 2011

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

5 x 960 s

0.0168
15000
650-661
fit
   
#73

05.189 / 03 / 2011

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

8 x 600 s

0.418
600-700
440-713
fit
fichier_dat
 
#74

19.171 / 03 / 2011

François Teyssier

SC 0.25 m
Lhires III 150 l/mm

3 x 600 s

0.418
600-700
440-713
fit
fichier_dat
 
#75

26.174 / 03 / 2011

François Teyssier

SC 0.25 m
LISA 300 l/mm

3 x 600 s

1000
400-720
fit
fichier_dat
 
#76

19.074 / 04 / 2011

Christian Buil

C11 0.28 m
LISA 300 l/mm

12 x 300 s
1000
400-750
fit
fichier_dat
 
#77

20.131 / 04 / 2011

François Teyssier

SC 0.25 m
LISA 300 l/mm

3 x 600 s

1000
400-720
fit
fichier_dat
 
#78

22.051 / 04 / 2011

Valèrie Desnoux

SC 0.23 cm
Lhires III 1200 l/mm

9 x 300 s

0.041
~10000
627-694
fit
fichier_dat
 
#79

26.995 / 04 / 2011

Thierry Garrel

0.21 m
Lhires III 2400 l/mm

5 x 960 s

0.0168
15000
650-661
fit
fichier_dat
 
#80

20.994 / 05 / 2011

François Teyssier

SC 0.25 m
LISA 300 l/mm

8 x 120 s

0.25
1000
400-730
fit
fichier_dat
 
#81

26.995 / 04 / 2011

Thierry Garrel

SC 0.36m
eShel

5 x 960 s

0.012
15000
443-688
fit
   

[1] spectral calibration on Ha and Hb - flux calibrated by intrumental response obtained on Vega - relative intensity to flux = 1 in the zone 595-605 nm

Rem : click on the Obs#number opens an image of the spectrum


Line identification

 

by F. Teyssier on june 30th, at the begining of the outburst. Note the high ionization lines [Fe VII] 5721 6087 (#1)

 

by C. Buil on august 25th (#9)

 

H alpha profile by Benjamin Mauclaire (#6)


Spectral variations

Outburst early stage


F. Teyssier Spectra #1 and #3

Note the evolution of TiO bands and the decrease of the highly ionized lines [Fe VII] in the early stage of the outburst


Eclipse ingress

Lines profile evolution at the begining of the eclise ingress by Christian Buil


The same in low resolution

 

After the outburst

 

19.03.2011 low resolution spectrum - High ionization lines such HeII and [FeVII] lines strongly increase

 

 

 

C.Buil (19/04) and F.Teyssier (20/04) spectra comparison. The two spectras obtained with a LISA spectrograph (Shelyak Instruments) :

 

T. Garrel 2011-01-24 Lhires III 2400 l/mm V. Desnoux 2011-04-22 Lhires III 1200 l/mm

H alpha profile evolution

2010-11-26 Phase = 0.035 2011-04-26 Phase = 0.206

Ha and Hb profiles

2010-05-25 Phase = 0.245 2011-05-25 Phase = 0.245

 


Line measurement

 

AAVSO CCD V = green line, right vertical scale

   

H alpha equivalent width (angströms)

Blue : Teyssier (Lhires III) Red : Buil (eShel)


Integration betweem 652 and 660 nm for eShel
between 651 and 661 for Lhires

AAVSO CCDV : green line

    (H alpha / H béta) ratio blue plots
vs. CCDV magnitude (AAVSO data)
green line
    H béta equivalent width (angströms)
       
   
  He II 4686 equivalent width (angströms)   He II 4686 relative to H Béta = 100
   

 

  He I 5876 equivalent width (angströms)   He I 5876 EW relative to H béta = 100
   
  [OIII]/HeI 5018 ratio (blue dots) and Mag V (solid green line)    
   
  [TiO]1 index as defined in Kenyon & Fernadez-Castro (1987)   Type Spectral déterminé à partir de l'indice [TiO]2

 

 

Luminosity comparison according phase computed with A. Siviero & al., 2009 Ephemeris
Min(V) = 2442690 + 853.8E

dotted line : 1975 eclipse : AAVSO Visual 10 days mean
solid line : current eclipse : AAVSO CCD V

     

 

 

 


 

 


CI Cyg profile with a Star Analyser
By Eric Sarrazin
19/09/2010
CI Cyg profile with a Star Analyser
By Pierre Dubreuil
11/12/2010

 

 


 

See also:

http://astrosurf.com/buil/cicyg/obs.htm

http://www.astronomie-amateur.fr/feuilles/Spectroscopie/SyS/CI%20Cyg.html

http://gabalou.canalblog.com/

and AAVSO web page :

http://www.aavso.org/vsots_cicyg


Publications about CI Cygni

 

CI Cygni 2010 outburst and eclipse, JAAVSO, 2001 : http://www.aavso.org/ejaavso

 

2009MNRAS.399.2139S
Mon. Not. R. Astron. Soc., 399, 2139-2145 (2009)
The ongoing 2008-09 outburst of CI Cyg.
SIVIERO A., MUNARI U., DALLAPORTA S., VALISA P., LUPPI V., MORETTI S., TOMASELLI S., BACCI S., BALLARDINI F., CHERINI G., GRAZIANI M., FRIGO A. and VAGNOZZI A.

1991AJ....101..637K
Astron. J., 101, 637-654 (1991)
On the nature of the symbiotic binary CI Cygni.
KENYON S.J., OLIVERSEN N.A., MIKOLAJEWSKA J., MIKOLAJEWSKI M., STENCEL R.E., GARCIA M.R. and ANDERSON C.M.

1985AcA....35...65M
Acta Astron., 35, 65-95 (1985)
On the nature of CI Cygni.
MIKOLAJEWSKA J.

1985IBVS.2834....1G
IAU Inform. Bull. Var. Stars, 2834, 1-4 (1985)
Photometry and spectrophotometry of symbiotic stars : CI Cyg, Z And, V1016 Cyg, HM Sge, HBV 475.
GRAVINA R.

1983AcA....33..403M
Acta Astron., 33, 403-429 (1983)
A spectrophotometric study of CI Cygni during the 1980 eclipse.
MIKOLAJEWSKA J. and MIKOLAJEWSKI M.

 

1983ApJ...268..250O
Astrophys. J., 268, 250-263 (1983)
Observational studies of the symbiotic stars. II. Emission-line relative intensity variations in CI Cygni, BF Cygni, AX Persei, and V1016 Cygni.
OLIVERSEN N.A. and ANDERSON C.M.

1983IBVS.2355....1M
IAU Inform. Bull. Var. Stars, 2355, 1-4 (1983)
Emission line intensity varations during the 1982 eclipse of CI Cygni.
MIKOLAJEWSKA J.

1981A&A....94..290I
Astron. Astrophys., 94, 290-293 (1981)
Spectrophotometric observations of CI Cyg in 1979.
IIJIMA T.

1981A&AS...46..257F
Astron. Astrophys., Suppl. Ser., 46, 257-261 (1981)
Observations spectroscopiques de CI Cygni.
FEHRENBACH C. and CHUN H.C.

1981IBVS.1945....1G
IAU Inform. Bull. Var. Stars, 1945, 1-2 (1981)
Spectroscopic observations of CI Cyg in 1980.
GRAVINA R.

 

1981IBVS.2041....1G
IAU Inform. Bull. Var. Stars, 2041, 1-4 (1981)
Spectroscopic observations of symbiotic stars in July and September 1981.
GRAVINA R.

1980IBVS.1759....1G
IAU Inform. Bull. Var. Stars, 1759, 1-2 (1980)
Spectroscopic observations of CI Cygni in 1978 and 1979.
GRAVINA R.

1954AnAp...17....6T
Ann. Astrophys., 17, 6 (1954)
Les spectres de BF Cygni, AX Persei et CI Cygni en 1952.
TCHENG M.L. and BLOCH M.

Other références

1987AJ.....93..938K
Astron. J., 93, 938-949 (1987)
The cool components of symbiotic stars. I. Optical spectral types.
KENYON S.J. and FERNANDEZ-CASTRO T.

Bibliography

The symbiotic stars, S.J. Kenyon, Cambridge University Press (1986, 2008)

 


[*] Aknowlegment to AAVSO CCD observers : Geir Klingenberg (KGE), Jan Suomela (SJAR), David Lane (LDJ), Menzies Kenneth (MZK), Teofilo Arranz (ATE), Tim Crowford (CTX), Douglas Slanson (SDN)


Conditions for use of data in publications                                                               
Note there is no validation check prior to adding spectra to this table. Users should verify the quality of the spectra with the observers concerned.    
Use of these data in research publications is encouraged subject to the following conditions:                                   
* The observers concerned should be contacted to confirm the particular acquisition and data reduction procedures used.
* Observers contributing a significant amount of data or whose data are pivotal to the findings of the paper should be included as co-authors; others should be thanks in the text.


 

 

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