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OBSID:
26761
 Title:
Spacetime and Spectra: Joint Chandra/EHT Observations of Sgr A* and M87  
Investigator:
Neilsen
 Observer:
Neilsen, Joey
 Phone:
610-519-6497
 Email:
jneilsen@villanova.edu
Target Name:
M 87
 Sequence Number:
704682
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_00D50B
 Raster Scan:
N
 Annotated DOT:
APR0824a

Proposal Number:
24700241
 Right Ascension:
187.706
 Declination:
12.3911
 Status:
archived
 Start Date:
2024-04-08 16:01:37
Category:
ACTIVE GALAXIES AND QUASARS
 Type:
GO
 AO Cycle:
24
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.2
 Order-1 Count Rate:

 Exposure Time:
5
 Time Remaining:
5.094
 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:
CUSTOM
 Starting Row:
449
 Row Count:
128
 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:
In April 2019, the Event Horizon Telescope released the first image of a black hole's silhouette. This M87* discovery image offered a glimpse of one of only two sources, M87* and Sgr A*, for which the EHT can achieve imaging quality sufficient to resolve their black hole shadows and provide a close-up view of accretion and jets at the horizon. Coordinated Chandra/EHT data placed crucial constraints on M87*'s energy budget, jet power, and spin. Sgr A* and M87 are both X-ray variable and new Chandra/EHT observations offer a chance to observe structures near the event horizon while tracking their high-energy variability. We propose Chandra/EHT obs of Sgr A* (4x25 ks) and M87 (2x5 ks) to enable searches for flares, hotspots, the bases of jets, and to aide priors for EHT image reconstruction.

Remarks:
The dates for the 2023 EHT campaign have not been set. When the EHT dates are fixed, we will update Mission Planning, ideally in Aug-Sept 2022. Based on 2017, we expect it will span ~14 days between mid-March and mid-April. Thus we have entered a 14-day window constraint with a 1-day coordination interval (shorter than M87's variability timescale). We are aware of a NuSTAR proposal for this target, but the number of pointings and their exposures are not set, so we request coordination with NuSTAR on a best effort basis.

psci Run:
115
 Processing Date:
Jul 18 2024
 psci Directory:
/nfs/maaxnew/r3/fm/acis127b/acis127.log
OBSID:
26761
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
704682
 Target Name:
M_87
 AO:
24
Start VCDU:
48635:008
 Start Time (UTC):
099:58574.407
 Stop Time (UTC):
099:63670.439
 Kilosecs:
5.1
 % Frames:
100.0
 # CCDs:
S2
# Frames:
9419
 # Events:
24214
 Events/sec:
4
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-116.4
Parameter Block:
0x00d50014
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te3x3
 BEP Mode:
F
 Start Row:
448
 # Rows:
128
Primary Exposure:
5
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
115

pgf@space.mit.edu Wed Mar 26 10:00:48 EST 2025