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OBSID:
29009
 Title:
Disk Wind Spectroscopy in a Bright Black Hole Transient     
Investigator:
Miller
 Observer:
Miller, Jon
 Phone:
617 529 5725
 Email:
jonmm@umich.edu
Target Name:
Swift J1727.8-1613
 Sequence Number:
402472
 Instrument:
ACIS-S
 Grating:
HETG
 SI Mode:
CC_00154B
 Raster Scan:
N
 Annotated DOT:
OCT2323a

Proposal Number:
25400268
 Right Ascension:
261.93
 Declination:
-16.2053
 Status:
archived
 Start Date:
2023-10-23 17:03:29
Category:
BH AND NS BINARIES
 Type:
TOO
 AO Cycle:
25
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
20
 Order-1 Count Rate:
300
 Exposure Time:
10.4
 Time Remaining:
11.4
 Reqd Start Time:

 Reqd Stop Time:
Period:

 Epoch:

 Start of Period:

 End of Period:

 PS Margin:

 PE Margin:

 Max Segments:
0

ACIS Mode:
CC
 Standard?:
No
 BEP Mode:
G
 Dropped Chip Count:
0
 Optional Chips:
S5
On-Chip Summing?:
No
 Row Sum:

 Column Sum:

 Frame Time:
Subarray Mode:

 Starting Row:

 Row Count:

 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?:
Yes
Chip:
S3
 Include Flag:
E
 Start Row:
1
 Start Column:
155
 Width:
100
 Height:
1023
 Lower Threshold:
0.08
 Pha Range:
13
 Sample:
10

Abstract:
Accretion disk winds in stellar-mass black holes may help to drive accretion through the disk itself, and may affect the evolution of the binary system. The resolution and throughput of the HETGS make it the ideal instrument to study accretion and ejection in the brightest of these sources, even in the XRISM era. The brightest sources have revealed accretion disk P Cygni profiles and fast outflows (v > 0.01c), partly by enabling spectroscopy with the HEG 3rd-order grating with a resolution of 15 eV. We propose to observe a bright stellar-mass black hole in a windy state in Cycle 25. We will seek to characterize the driving mechanisms that propel the wind, the mass outflow rate, and how these factors connect to the disk.

Remarks:
The source has hit a threshold of 5 Crab, which is still very bright. Adding a SIM-Z offset to reduce the count rates due to two arms of the HETGS, avoiding telemetry saturation.

psci Run:
385
 Processing Date:
Nov 20 2023
 psci Directory:
/nfs/maaxnew/r3/fk/acis125e/acis125.log
OBSID:
29009
 SIM Mode:
ACIS-S
 OTG Mode:
HETG
 Seq Number:
402472
 Target Name:
Swift_J1727.8-1
 AO:
25
Start VCDU:
130520:104
 Start Time (UTC):
296:62689.703
 Stop Time (UTC):
296:74196.887
 Kilosecs:
11.5
 % Frames:
100.0
 # CCDs:
S5
# Frames:
7886
 # Events:
4559004
 Events/sec:
396
 PSCI errors:
0
 % drops:
53.9
 Bias Errs:
0
 FP Temp:
-112.2
Parameter Block:
0x00154014
 Window Block:
0x0011c014
 # Windows:
1
 FEP Mode:
Cc3x3
 BEP Mode:
G
 Start Row:
0
 # Rows:
512
Primary Exposure:
-
 Secondary Exposure:
-
 Duty Cycle:
-
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
385

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