\begin{table}%t1
\caption{\label{chandraobs}All observations of \rxj\ listed in chronological order.}
\begin{tabular}{rlccccr}
\hline\hline\noalign{\smallskip}
Obs. Id. & Instrument/setup & Counts & Counts & MJD & Start date &Effective \\
& & (120--400~eV) & (400--1000~eV) & & & exposure\\     
& & & & [days]&& [ks]\\
\hline
rp300338n00& PSPC & \multicolumn{2}{c}{5374} & 49~258 & 1993 Sep.~27 &  3.22 \\
rh300508n00 & HRI & \multicolumn{2}{c}{1259}				      & 50~199 & 1996 Apr.~25 &  3.13 \\  
rh180100n00 & HRI&\multicolumn{2}{c}{1197}& 50~211 & 1996 May~7 &  3.57 \\ 
rh300508n01&HRI&\multicolumn{2}{c}{493}& 50~354 & 1996 Sep.~27 &  1.41 \\  
rh400884n00& HRI&\multicolumn{2}{c}{13381}& 50~391&1996 Nov.~3 & 33.57 \\
h400944n00&HRI& \multicolumn{2}{c}{3054}& 50~924&1998 Apr.~20 &3.57\\	 
368$^{1}$ & HRC-S/LETG & \multicolumn{2}{c}{2722}& 51~575 & 2000 Feb.~1 &  5.40 \\
745$^{1}$ & HRC-S/LETG & \multicolumn{2}{c}{9392}& 51~576 & 2000 Feb.~2 & 26.26 \\
369$^{1}$ & HRC-S/LETG & \multicolumn{2}{c}{2660} & 51~579 & 2000 Feb.~4 &  6.12\\
0078 S3	& EPIC-pn/FF thin&241~783 & 115~287 & 51~677&2000 May~13 & 58.60 \\  
S1 & EPIC-MOS1/FF thin & 69~623 & 43~977 & 51~677 & 2000 May 13 & 61.98 \\  
S2 & EPIC-MOS2/SW thin &  68~010 &  40~818 & 51~677 & 2000 May 13 & 61.99 \\ 0175 S3	& EPIC-pn/FF med & 103~491 &  55~743 & 51~870 & 2000 Nov.~21 & 25.65 \\  
S7 & EPIC-MOS1/LW med &  15~765 &  11~662 & 51~870 & 2000 Nov.~21 & 18.00 \\ 2774$^{2}$ & ACIS-CC &  13~455  &  15~648 & 52~248 & 2001 Dec.~4 & 15.01 \\  
2773$^{2}$ & ACIS-CC &   9452 &  11~646 & 52~248 & 2001 Dec.~5 & 10.61 \\  
2771$^{2}$ & ACIS-CC & 876 &   1553 & 52~250 & 2001 Dec.~6 &  1.86 \\
2772$^{2}$ & ACIS-CC &   3537 &   4487 & 52~250 & 2001 Dec.~6 &  4.05 \\  
0533 S3	& EPIC-pn/FF thin & 137~951 &  72~150 & 52~585 & 2002 Nov.  6 & 28.38 \\  
S1 & EPIC-MOS1/FF thin &  27~987 &  21~892 & 52~585 & 2002 Nov.~6 & 29.99\\ S2 & EPIC-MOS2/FF thin &  29~169 &  22~192 & 52~585 & 2002 Nov.~6 & 29.99\\  
0534 S3	& EPIC-pn/FF thin & 145~057 &  76~095 & 52~587 & 2002 Nov.  8 & 30.18 \\  
S1 & EPIC-MOS1/FF thin	 &  28~168 &  22~112 & 52~587 & 2002 Nov.~8 & 31.80 \\  
S2 & EPIC-MOS2/FF thin	 &  28~954 &  22~768 & 52~587 & 2002 Nov.~8 & 31.79 \\  
0622 U2	& EPIC-pn/SW thick & 123~199 &  94~655 & 52~762 & 2003 May~2 & 72.79 \\  
S5 & EPIC-MOS1/FF med &  21~204 &  18~741 & 52~762 & 2003 May~2 & 29.98 \\  
S3 & EPIC-MOS1/FF thin &  28~433 &  23~754 & 52~762 & 2003 May~2 & 33.59 \\  
S6 & EPIC-MOS2/FF med &  21~988 &  19~650 & 52~762 & 2003 May  2 & 29.99 \\  
S4 & EPIC-MOS2/FF thin &  30~901 &  24~413 & 52~762 & 2003 May  2 & 33.59 \\ 0711 S8	& EPIC-pn/SW med &  83~151 &  60~557 & 52~940 & 2003 Oct 27 & 24.90 \\  
S3 & EPIC-MOS1/FF thin &10~841 &11~937 & 52~940 & 2003 Oct.~27 & 13.90 \\  
S5 & EPIC-MOS1/LW thin &  10~547 &  11~769 & 52~940 & 2003 Oct.~27 & 15.71 \\ 
S4 & EPIC-MOS2/FF thin &  11~649 &  12~392& 52~940 & 2003 Oct.~27 & 13.91 \\ S6 & EPIC-MOS2/LW thin	 &  11~943 &  12~382 & 52~940 & 2003 Oct.~27 & 15.71 \\  
4666$^{3}$ & ACIS-CC &   5606 &  13~094 & 53~010 & 2004 Jan.~6 & 10.12 \\  
4667$^{3}$ & ACIS-CC &   2678 &   5835 & 53~011 & 2004 Jan.~7 &  4.79 \\  
4668$^{3}$ & ACIS-CC &   2121 &   4918 & 53~016 & 2004 Jan.~11 &  5.16 \\  
4669$^{3}$ & ACIS-CC &   1890 &   4277 & 53~023 & 2004 Jan.~19 &  5.22 \\  
5305$^{4}$ & HRC-S/LETG & \multicolumn{2}{c}{13~275}& 53~062 & 2004 Feb.~27 & 35.70 \\  
0815 S1	& EPIC-pn/FF thin   & 130~683 &  93~280 & 53~147 & 2004 May 22 &41.30 \\    
S2 & EPIC-MOS1/FF thin &35~853 &  41~178 & 53~147 & 2004 May 22 & 45.21 \\   
S3 & EPIC-MOS2/FF thin &  35~915 &  42~318 & 53~147 & 2004 May 22 & 45.22 \\ 
4670$^{5}$ & ACIS-CC &   5723 &  12~329 & 53~221 & 2004 Aug.~3 & 10.13 \\
4671$^{5}$ & ACIS-CC &   2778 & 6318 & 53~223 & 2004 Aug.~5 &  5.15 \\
4672$^{5}$ & ACIS-CC &   2483 &   5789 & 53~227 & 2004 Aug.~9 &  5.12 \\  
4673$^{5}$ & ACIS-CC &   2527 & 6034 & 53~244 & 2004 Aug.~23 & 5.13 \\	
5581$^{6}$ & HRC-S/LETG & \multicolumn{2}{c}{30~998} & 53~393 & 2005 Jan.~23 & 68.20 \\    
0986 S3	& EPIC-pn/FF thin & 181~754 & 131~146 & 53~488 & 2005 Apr.~28 & 51.43 \\    
S1 & EPIC-MOS1/SW thin &  32~400 &  36~475 & 53~488 & 2005 Apr.~28 & 53.05 \\	      
S2 & EPIC-MOS2/SW thin &  34~456 &  38~266 & 53~488 & 2005 Apr.~28 & 53.06\\	      
5582$^{7}$ & HRC-S/LETG & \multicolumn{2}{c}{35~777} &	53~523 & 2005 Jun.~1 & 70.17 \\	      
6364$^{8}$ & HRC-S/LETG & \multicolumn{2}{c}{22~210} & 53~610 & 2005 Aug.~27 & 38.87 \\	      
1060 S3	& EPIC-pn/FF thin & 175~481&120~913 & 53~636 & 2005 Sep.~23&51.14\\	      
S1 & EPIC-MOS1/SW thin 	 &  33~710 &  37~070 &53~636&2005 Sep.~23&52.76 \\	  
S2 & EPIC-MOS2/SW thin& 33~977 & 37~706 & 53~636 & 2005 Sep.~23 & 52.77\\	  
6369$^{9}$ & HRC-S/LETG & \multicolumn{2}{c}{7696}&	53~652 & 2005 Oct.~8 & 26.26 \\
7177$^{9}$ & HRC-S/LETG & \multicolumn{2}{c}{2532} & 53~653 & 2005 Oct.~9 &  8.04 \\	    
1086 S3	& EPIC-pn/FF thin & 167~725 & 117~828 & 53~687 & 2005 Nov.~12 & 37.84 \\	      
S1 & EPIC-MOS1/SW thin 	 &  25~265 &  27~091 & 53~687 & 2005 Nov.~12 & 39.46 \\			  
S2 & EPIC-MOS2/SW thin 	 &  25~045 &  27~580 & 53~687 & 2005 Nov.~12 & 39.47 \\		  
7243$^{10}$ & HRC-S/LETG & \multicolumn{2}{c}{5931} &	53~718 & 2005 Dec.~14 & 17.18 \\
7244$^{10}$  & HRC-S/LETG & \multicolumn{2}{c}{4927} &	53~718 & 2005 Dec.~15 & 16.29 \\
7245$^{10}$ & HRC-S/LETG & \multicolumn{2}{c}{5249} &	53~718 & 2005 Dec.~16 & 17.19 \\
5584$^{10}$ & HRC-S/LETG & \multicolumn{2}{c}{5321} &	53~718 & 2005 Dec.~17 & 14.19 \\	  
{\it 7251} & {\it HRC-S/LETG} & \multicolumn{2}{c}{{\it 4787}} & {\it 53~775} & {\it 2006 Sep.~9}  & {\it 10.65} \\    	 	    
1181 S1	& EPIC-pn/FF thin &  89~015 &  59~524 &	53~877 & 2006 May 22 & 20.04 \\	       
S2 & EPIC-MOS1/SW thin 	 &  13~652 &  14~219 &	53~877 & 2006 May 22 & 21.66 \\		  
S3 & EPIC-MOS2/SW thin 	 &  15~045 &  15~048 &	53~877 & 2006 May~22 & 21.66 \\    
1265 S1	& EPIC-pn/FF thin &  89~852 &  60~883 & 54~044 & 2006 Nov.~5 & 20.04 \\
S2 & EPIC-MOS1/FF thin &  12~414 &  12~296 & 54~044 & 2006 Nov.~5 & 21.61 \\	 
S3 & EPIC-MOS2/FF thin	 &  15~291  &  14~653 & 54~044 & 2006 Nov.~5 & 21.62 \\	 
1356 S1	& EPIC-pn/FF thin  &  89~411 &  57~483 & 54~226 & 2007 May  5 & 20.04 \\	 
S2 & EPIC-MOS1/FF thin	 &  16~690 &  16~685 & 54~226 & 2007 May  5 & 21.61 \\	 
S3 & EPIC-MOS2/FF thin	 &  17~147  &  16~818 & 54~226 & 2007 May  5 & 21.62 \\   
1454 S1	& EPIC-pn/FF thin  & 102~917 &  64~833 & 54~421 & 2007 Nov.~17 & 23.06 \\   
S2 & EPIC-MOS1/FF thin	 &  18~674 &  18~197 & 54~421 & 2007 Nov.~17 & 24.62 \\   
S3 & EPIC-MOS2/FF thin &  19~029 &  18~416 & 54~421 & 2007 Nov.~17 & 24.62 \\   
10861$^{11}$	& HRC-S/LETG & \multicolumn{2}{c}{4240}				      &	54~851 & 2009 Jan 20 & 11.91 \\
10700$^{11}$   	& HRC-S/LETG & \multicolumn{2}{c}{14~053}				      &	54~876 & 2009 Feb.~14 & 21.82 \\	    
1700 S3	& EPIC-pn/FF thin &  37~085 &  30~806 & 54~913 & 2009 Mar.~21 & 10.84 \\		 
U2	& EPIC-MOS1/FF thin &  11~481  &  11~876 & 54~912 & 2009 Mar.~21 & 17.69 \\		 
U2	& EPIC-MOS2/FF thin &  11~936 &  11~556 & 54~912 & 2009 Mar.~21 & 17.69 \\
10701$^{12}$ & HRC-S/LETG & \multicolumn{2}{c}{15647}				      & 55~086 & 2009 Sep.~11 & 33.17 \\	 
1792 S3	& EPIC-pn/FF thin  &  65~407 &  48~105 & 55~096 & 2009 Sep.~22 & 17.90 \\		 
S1	& EPIC-MOS1/SW thin &  12~524 &  11~919 & 55~096 & 2009 Sep.~22 & 19.22 \\	       
S2	& EPIC-MOS2/SW thin &  12~724 &  11~993 & 55~096 & 2009 Sep.~22 & 19.24 \\		
\hline									
\end{tabular}
\tablefoot{Observation 7251, in {\it italic}, is not used in this work (see Sect.~3). The identifier marks the merged data sets: observations with the same tag are merged into one data set. Counts for ROSAT and Chandra HRC were not divided into soft (120--400~eV) and hard (400--1000~eV) band (see Sect.~3), hence we list the total number of counts. The count numbers for the HRC observations are comparable to those listed in KvK05, but are a factor 100 less than those listed in vK07 (probably due to missprint in vK07) although the data handling in all three works (KvK05, vK07 and this work) is comparable. The count numbers of all other observations are in good agreement. For details on ROSAT and \xmm\ observations we refer to \cite{2004MNRAS.351.1099C} and (\citealt{2009AetA...498..811H} and Sects.~2,~3 this work), respectively.}
\end{table}