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OBSID:
23534
 Title:
CHANDRA CYCLE 22 SPATIAL AND SPECTRAL MONITORING OF SN1987A    
Investigator:
Burrows
 Observer:
Park, Sangwook
 Phone:
+1 (814) 753-2828
 Email:
s.park@uta.edu
Target Name:
SNR 1987A
 Sequence Number:
503209
 Instrument:
ACIS-S
 Grating:
HETG
 SI Mode:
TE_00BACB
 Raster Scan:
N
 Annotated DOT:
OCT2521b

Proposal Number:
22500040
 Right Ascension:
83.8667
 Declination:
-69.2698
 Status:
archived
 Start Date:
2021-10-25 20:30:37
Category:
SN, SNR AND ISOLATED NS
 Type:
GO
 AO Cycle:
22
 Dither Flag:
Y
 Y Offset:
0.15
 Z Offset:
-0.25
Est. Count Rate:
0.13
 Order-1 Count Rate:
0.2
 Exposure Time:
29
 Time Remaining:
28.089
 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
 Dropped Chip Count:
0
 Optional Chips:
S0 S5
On-Chip Summing?:
No
 Row Sum:

 Column Sum:

 Frame Time:
Subarray Mode:
CUSTOM
 Starting Row:
351
 Row Count:
256
 Subarray Frame Time:

Duty Cycle?:
No
 Cycle Count:
0
 Primary Exp Time:

 Secondary Exp Time:
Event Filter?:
Yes
 Filter Threshold:
0.24
 Filter Range:
12
 Bias Requested?:
No
 Bias Frequency:

 Bias After?:
No
 Spatial Window?:
No

Abstract:
SN 1987A presents a unique opportunity to study the birth and early developmental stages of a supernova remnant in high spatial and spectral resolution. SN 1987A is currently at an important transitional stage in its development, as the blast wave has left the dense equatorial ring (ER) and is now probing the hitherto unseen circumstellar material beyond the ER, providing valuable information on the supernova progenitor. Meanwhile, the reverse shock should soon encounter the supernova ejecta, heating this enriched gas to millions of degrees and making it accessible to X-ray spectroscopy. We propose to continue our program of monitoring SN1987A at roughly six month intervals in Cycle 22.

Remarks:
We prefer as much time as possible (preferably > 50 ks) in a single uninterrupted observation (for image deconvolution). Subarray is used to minimize frame time (and pileup in 0th order image), and the start row is chosen to place the OVIII line in the MEG minus order in the subarray. Window constraint was entered to force two observations separated by about six months, with roll angles as specified. The dates for the window constraints were chosen to meet the stated roll range while also separating the two pointings for monitoring purposes.

psci Run:
223
 Processing Date:
Oct 31 2021
 psci Directory:
/nfs/maaxnew/r3/fc/acis117d/acis117.log
OBSID:
23534
 SIM Mode:
ACIS-S
 OTG Mode:
HETG
 Seq Number:
503209
 Target Name:
SNR_1987A
 AO:
22
Start VCDU:
54214:032
 Start Time (UTC):
298:74844.145
 Stop Time (UTC):
299:16537.564
 Kilosecs:
28.1
 % Frames:
100.0
 # CCDs:
S6
# Frames:
24621
 # Events:
401356
 Events/sec:
14
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-115.7
Parameter Block:
0x00bac014
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te3x3
 BEP Mode:
F
 Start Row:
350
 # Rows:
256
Primary Exposure:
11
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
223

pgf@space.mit.edu Sat Mar 29 10:37:19 EST 2025