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OBSID:
25232
 Title:
Sleuthing the star cluster X-ray sources in the outer halo of the giant elliptical Cen A
Investigator:
Strader
 Observer:
Strader, Jay
 Phone:
5178845605
 Email:
strader@pa.msu.edu
Target Name:
CEN-A KV20-212
 Sequence Number:
601557
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_006C8B
 Raster Scan:
N
 Annotated DOT:
SEP0522a

Proposal Number:
23620148
 Right Ascension:
200.791
 Declination:
-43.8745
 Status:
archived
 Start Date:
2022-09-06 13:10:12
Category:
NORMAL GALAXIES
 Type:
GO
 AO Cycle:
23
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.0007
 Order-1 Count Rate:

 Exposure Time:
7
 Time Remaining:
7.061
 Reqd Start Time:

 Reqd Stop Time:
Period:

 Epoch:

 Start of Period:

 End of Period:

 PS Margin:

 PE Margin:

 Max Segments:
0

ACIS Mode:
TE
 Standard?:
No
 BEP Mode:
VF
On-Chip Summing?:
No
 Row Sum:

 Column Sum:

 Frame Time:
Subarray Mode:
NONE
 Starting Row:
0
 Row Count:
1023
 Subarray Frame Time:

Duty Cycle?:
No
 Cycle Count:
0
 Primary Exp Time:

 Secondary Exp Time:
Event Filter?:
No
 Filter Threshold:

 Filter Range:

 Bias Requested?:
No
 Bias Frequency:

 Bias After?:
No
 Spatial Window?:
No

Abstract:
Half or more of the X-ray sources in giant elliptical galaxies are low-mass X-ray binaries dynamically formed in globular clusters. There is also evidence that some of the most massive globular clusters in these galaxies did not form independently, but are instead tidally stripped central nuclear star clusters of satellites accreted by the main galaxy. In this case, the presence of an X-ray source could instead point to the presence of a relic supermassive black hole in the center of the star cluster. Here we propose Chandra imaging of nine very massive star clusters in the outer halo of the giant early-type galaxy Cen A (NGC 5128) to search for evidence that they host X-ray sources, and potentially low-luminosity accreting central black holes.

psci Run:
195
 Processing Date:
Sep 7 2022
 psci Directory:
/nfs/maaxnew/r3/fg/acis121c/acis121.log
OBSID:
25232
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
601557
 Target Name:
CEN-A_KV20-212
 AO:
23
Start VCDU:
46820:008
 Start Time (UTC):
249:48623.300
 Stop Time (UTC):
249:55696.936
 Kilosecs:
7.1
 % Frames:
100.0
 # CCDs:
S4
# Frames:
2252
 # Events:
234740
 Events/sec:
33
 PSCI errors:
1
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-110.9
Parameter Block:
0x006c8034
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te5x5
 BEP Mode:
F
 Start Row:
0
 # Rows:
1024
Primary Exposure:
31
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
195

pgf@space.mit.edu Mon Apr 14 22:55:55 EST 2025