1. The states of Scorpius X-1 v.s. the 107 events 吳宇智 (Yu-chih, Wu) 2006/10/24

2. Scorpius X-1 The brightest X-ray source in the sky. The brightest X-ray source in the sky. Low-mass X-ray binary(LMXB) — Low-mass X-ray binary(LMXB) — neutron star & neutron star & donor donor Distance ： 2.8kpc Distance ： 2.8kpc inclination to the eciptic ： 6 o Z source

3. A group of LMXBs. A group of LMXBs. CDs(color diagrams) and HIDs(hardness intensity diagrams) have 3 branches, which look like the shape of ” Z ”. CDs(color diagrams) and HIDs(hardness intensity diagrams) have 3 branches, which look like the shape of ” Z ”. Actually, it ’ s not like “ Z ” for Sco X-1. Actually, it ’ s not like “ Z ” for Sco X-1.

4. States 3 branches means 3 branches means 3 states: 3 states: H(horizontal) H(horizontal) N(normal) N(normal) F(flaring) F(flaring) F H N

5. 107 events Everybody knows. Everybody knows.

6. Rossi X-ray Timing Explorer RXTE 1996~2002 archival data RXTE 1996~2002 archival data PCA(proportional counting array) “ standard 2 ” mode PCA(proportional counting array) “ standard 2 ” mode

7. Good Time Intervals ELV(elavation angle): the angle between the Earth's limb and the pointing direction. ELV(elavation angle): the angle between the Earth's limb and the pointing direction. ELV>10 degree ELV>10 degree OFFSET: the difference between the source position and the pointing of the satellite. OFFSET: the difference between the source position and the pointing of the satellite. OFFSET<0.02 degree OFFSET<0.02 degree SAA(South Atlantic Anomaly): a ‘ hole ’ in the geomagnetic field which allows cosmic rays to penetrate further than usual. SAA(South Atlantic Anomaly): a ‘ hole ’ in the geomagnetic field which allows cosmic rays to penetrate further than usual. Time before SAA or 30min after entering SAA Time before SAA or 30min after entering SAA

8. Hard Intensity Diagrams X-axis: intensity(counts/sec) X-axis: intensity(counts/sec) Y-axis: hard color ratio, or HCR Y-axis: hard color ratio, or HCR bin time: 160sec bin time: 160sec HCR: (9.1~18.2keV)/(6.9~9.1keV) HCR: (9.1~18.2keV)/(6.9~9.1keV)

9. epoch1 ~3/21/1996 (exposure: 16,697 sec) epoch3 3/21/1996~4/15/1999 (exposure: 473,415 sec)

10. epoch4 3/22/1999~5/13/2000 (exposure: 58,991 sec) epoch5 5/13/2000~ (exposure: 15,168 sec)

11. Take this data as an example: Take this data as an example: Observe time: Apr. 18~24, 1997 Observe time: Apr. 18~24, 1997 Exposure time: 68,068 sec Exposure time: 68,068 sec It moves continuously with time. It moves continuously with time. slowly at slowly at HB, NB, but HB, NB, but fast at FB. fast at FB.

12. hard color- soft color SCR: (2.3~4.4keV)/(4.4~6.9keV) soft color- soft intensity hard color- hard intensity soft color- total intensity H N F H N F

13. (5.1~18.5keV)/(3.4~5.1keV)(5.8~14.8)/(3.7~5.8keV) (6.5~14.8keV)/(4.1~6.5keV)(7.6~14.8keV)/(5.8~7.6keV)

14. bin time: 16 sec bin time: 1600 sec

15. It seems no relationship between the “ states ” and the events. It seems no relationship between the “ states ” and the events.

16. Thnak you!