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OBSID:
26485
 Title:
Diffuse Hard X-ray Bubble around NGC 4631       
Investigator:
Hodges-Kluck
 Observer:
Hodges-Kluck, Edmund
 Phone:
17203948992
 Email:
edmund.hodges-kluck@nasa.gov
Target Name:
ngc 4631
 Sequence Number:
601545
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_00972B
 Raster Scan:
N
 Annotated DOT:
AUG0122a

Proposal Number:
23610025
 Right Ascension:
190.533
 Declination:
32.5415
 Status:
archived
 Start Date:
2022-08-05 05:19:57
Category:
NORMAL GALAXIES
 Type:
GO
 AO Cycle:
23
 Dither Flag:
Y
 Y Offset:
-2.5
 Z Offset:
0
Est. Count Rate:
0.007
 Order-1 Count Rate:

 Exposure Time:
23
 Time Remaining:
21.081
 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:
1
 Optional Chips:
S4
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:
Diffuse, kpc-scale, hard X-ray halos have been discovered around several nearby, star-forming galaxies, but their origin remains unknown. Here we propose to observe NGC 4631, where archival Chandra data indicates diffuse, hard X-ray emission trapped within a superbubble along with hot gas and cosmic rays. The similar extent of each component will show whether the hard X-rays are related to shocks, cosmic rays flowing out of the disk, or another mechanism. The goal of this proposal is to confirm the bubble morphology of the diffuse, hard X-rays and precisely measure the spectral index, which will discriminate between several thermal and nonthermal processes.

psci Run:
37
 Processing Date:
Aug 14 2022
 psci Directory:
/nfs/maaxnew/r3/fg/acis121a/acis121.log
OBSID:
26485
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
601545
 Target Name:
ngc_4631
 AO:
23
Start VCDU:
14222:072
 Start Time (UTC):
217:20517.279
 Stop Time (UTC):
217:41609.735
 Kilosecs:
21.1
 % Frames:
100.0
 # CCDs:
S2
# Frames:
6936
 # Events:
312643
 Events/sec:
14
 PSCI errors:
1
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-113.0
Parameter Block:
0x00972024
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te3x3
 BEP Mode:
F
 Start Row:
0
 # Rows:
1024
Primary Exposure:
30
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
37

pgf@space.mit.edu Mon Mar 31 10:36:39 EST 2025