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OBSID:
23584
 Title:
Late time Chandra monitoring of the recently-discovered radio-loud magnetar Swift J1818.0-1607
Investigator:
Younes
 Observer:
Younes, George
 Phone:
2024135106
 Email:
george.a.younes@nasa.gov
Target Name:
Swift J1818.0-1607
 Sequence Number:
503259
 Instrument:
ACIS-I
 Grating:
NONE
 SI Mode:
TE_00D42B
 Raster Scan:
N
 Annotated DOT:
NOV0121a

Proposal Number:
22500547
 Right Ascension:
274.501
 Declination:
-16.1312
 Status:
archived
 Start Date:
2021-11-05 16:34:46
Category:
SN, SNR AND ISOLATED NS
 Type:
TOO
 AO Cycle:
22
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.0027
 Order-1 Count Rate:

 Exposure Time:
10
 Time Remaining:
10.124
 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:
1
 Optional Chips:
I0 I1 I2
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:
The fifth radio-loud magnetar, Swift J1818.0-1607, has recently been discovered with Swift/BAT and detected with a suite of radio and X-ray observatories. The source spin period of 1.36 seconds and its period derivative imply a magnetar strength field of 4e14 G, a very young spin-down age of 260 years, and a spin down power of 1e36 erg/s, the largest by far among all magnetars, and rivaling those of rotation-powered pulsars. Hence Swift J1818.0-1607 may represent the ultimate link between these two populations. Here, we propose a late-time Chandra monitoring campaign of this recently-discovered radio-loud magnetar to track its decay trend towards quiescence, establish its quiescent flux level, and search for arcsecond scale extended emission.

psci Run:
259
 Processing Date:
Nov 16 2021
 psci Directory:
/nfs/maaxnew/r3/fc/acis117e/acis117.log
OBSID:
23584
 SIM Mode:
ACIS-I
 OTG Mode:
NONE
 Seq Number:
503259
 Target Name:
Swift_J1818.0-1
 AO:
22
Start VCDU:
82755:088
 Start Time (UTC):
309:60769.622
 Stop Time (UTC):
309:70905.675
 Kilosecs:
10.1
 % Frames:
100.0
 # CCDs:
I3
# Frames:
3227
 # Events:
181889
 Events/sec:
17
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-114.4
Parameter Block:
0x00d42014
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te5x5
 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:
259

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