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OBSID:
26371
 Title:
The hunt for a new ultra-compact X-ray binary in M87's globular cluster system 
Investigator:
Dage
 Observer:
Dage, Kristen
 Phone:
2484913010
 Email:
kcdage@msu.edu
Target Name:
[PLP2016] 188.073826+12.107060
 Sequence Number:
402300
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_0088EB
 Raster Scan:
N
 Annotated DOT:
MAR0623a

Proposal Number:
23400119
 Right Ascension:
188.074
 Declination:
12.1071
 Status:
archived
 Start Date:
2023-03-06 03:26:31
Category:
BH AND NS BINARIES
 Type:
GO
 AO Cycle:
23
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.012
 Order-1 Count Rate:

 Exposure Time:
16
 Time Remaining:
16.067
 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:
F
 Dropped Chip Count:
2
 Optional Chips:
S0 S1 S4 S5
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:
With a short 40ks observation, this proposal aims to identify the second ever candidate extragalactic ultra-compact X-ray binary (UCXB) located in a globular cluster (GC) in M87's outer halo. The number of GCs that host UCXBs have implications for theoretical predictions of how UCXBs form in GCs, and these implications carry over to major questions about the source of gravitational wave emission.?UCXBs are difficult to identify outside of the Miky Way. However,?forbidden oxygen emission lines are indicative of accretion from a white dwarf, and thus a newly identified GC in M87's outer halo with this feature is an excellent UCXB candidate, The proposed dataset would further cement that status. The sample of candidate extragalactic UCXBs is extremely small, and thus any addition is valuable.

psci Run:
230
 Processing Date:
Mar 20 2023
 psci Directory:
/nfs/maaxnew/r3/fi/acis123d/acis123.log
OBSID:
26371
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
402300
 Target Name:
[PLP2016]_188.0
 AO:
23
Start VCDU:
44793:096
 Start Time (UTC):
065:13424.044
 Stop Time (UTC):
065:29503.010
 Kilosecs:
16.1
 % Frames:
100.0
 # CCDs:
S4
# Frames:
5119
 # Events:
478871
 Events/sec:
29
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-113.9
Parameter Block:
0x00958024
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te3x3
 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:
230

pgf@space.mit.edu Sat Mar 29 10:37:19 EST 2025