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OBSID:
25405
 Title:
Chandra Observations of New Quadruply Lensed Quasars     
Investigator:
Pooley
 Observer:
Pooley, David
 Phone:
6172301098
 Email:
davepooley@me.com
Target Name:
[KDW2018] GRAL J113100-441959
 Sequence Number:
704449
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_004A4B
 Raster Scan:
N
 Annotated DOT:
JUN2623a

Proposal Number:
23700533
 Right Ascension:
172.75
 Declination:
-44.3333
 Status:
archived
 Start Date:
2023-06-27 01:06:25
Category:
ACTIVE GALAXIES AND QUASARS
 Type:
GO
 AO Cycle:
23
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.0188
 Order-1 Count Rate:

 Exposure Time:
32
 Time Remaining:
29.712
 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:
VF
 Dropped Chip Count:
0
 Optional Chips:
I2 I3 S1 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:
Chandra observations of quadruply gravitationally lensed quasars have a unique power to address several fundamental astrophysical issues. These observations have been used to (1) determine the cause of flux ratio anomalies, (2) measure the sizes of quasar accretion disks, (3) determine the dark matter content of the lensing galaxies, and (4) measure the stellar mass-to-light ratio (in fact, this is the only way to measure the stellar mass-to-light ratio beyond the solar neighborhood). In all cases, the main source of uncertainty in the results is the small size of the sample of known quads; until recently, only about a dozen systems were available for study with Chandra. We propose Chandra observations of four newly discovered quads.

psci Run:
352
 Processing Date:
Jun 29 2023
 psci Directory:
/nfs/maaxnew/r3/fj/acis124d/acis124.log
OBSID:
25405
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
704449
 Target Name:
[KDW2018]_GRAL_
 AO:
23
Start VCDU:
80043:080
 Start Time (UTC):
178:05009.490
 Stop Time (UTC):
178:34732.741
 Kilosecs:
29.7
 % Frames:
100.0
 # CCDs:
I6
# Frames:
9171
 # Events:
1000622
 Events/sec:
33
 PSCI errors:
3
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-119.5
Parameter Block:
0x004a4034
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te5x5
 BEP Mode:
F
 Start Row:
0
 # Rows:
1024
Primary Exposure:
32
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
352

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