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OBSID:
27363
 Title:
Followup observations of the purported X-ray counterpart of M31*   
Investigator:
Garmire
 Observer:
Nynka, Melania
 Phone:
9738791918
 Email:
mnynka@mit.edu
Target Name:
M31*
 Sequence Number:
704842
 Instrument:
ACIS-I
 Grating:
NONE
 SI Mode:
TE_00866B
 Raster Scan:
N
 Annotated DOT:
AUG0524b

Proposal Number:
24700106
 Right Ascension:
10.6847
 Declination:
41.269
 Status:
archived
 Start Date:
2024-08-05 08:11:22
Category:
ACTIVE GALAXIES AND QUASARS
 Type:
GTO
 AO Cycle:
24
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.006
 Order-1 Count Rate:

 Exposure Time:
26
 Time Remaining:
26.089
 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
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:
M31*, the supermassive black hole that is in the center of the Andromeda Galaxy (M31), is a well studied low-luminosity active galactic nucleus (LLAG with a mass of M~ 1.4E8 ?_?. Underluminous LLAGN are difficult to study, with Sagittarius A* being the only other observed candidate. Since the launch of the Chandra X-ray Observatory, the putative X-ray counterpart of M31* has been observed in a low-quiescent state with occasional, weak X-ray flares. After a major outburst in January 2006, M31* became very active. A long term lightcurve was published in 2010 and recently extended to 2016. We request an additional 120ks of exposure to extend the lightcurve to 2022.

psci Run:
61
 Processing Date:
Aug 11 2024
 psci Directory:
/nfs/maaxnew/r3/fn/acis128a/acis128.log
OBSID:
27363
 SIM Mode:
ACIS-I
 OTG Mode:
NONE
 Seq Number:
704842
 Target Name:
M31*
 AO:
24
Start VCDU:
99080:096
 Start Time (UTC):
218:30431.812
 Stop Time (UTC):
218:56533.670
 Kilosecs:
26.1
 % Frames:
100.0
 # CCDs:
I4
# Frames:
8310
 # Events:
423364
 Events/sec:
16
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-115.0
Parameter Block:
0x00866024
 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:
61

pgf@space.mit.edu Tue Apr 8 9:48:31 EST 2025