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OBSID:
24776
 Title:
High Resolution Spectroscopy of the Spectral Feature in CCO J0821-4300  
Investigator:
Paerels
 Observer:
Paerels, Frederik
 Phone:
212 854 0181
 Email:
frits@astro.columbia.edu
Target Name:
PSR J0821-4300
 Sequence Number:
503163
 Instrument:
HRC-S
 Grating:
LETG
 SI Mode:
HSE_0002B
 Raster Scan:
N
 Annotated DOT:
AUG0921a

Proposal Number:
21500210
 Right Ascension:
125.489
 Declination:
-43.0048
 Status:
archived
 Start Date:
2021-08-09 15:32:41
Category:
SN, SNR AND ISOLATED NS
 Type:
GO
 AO Cycle:
21
 Dither Flag:
Y
 Y Offset:

 Z Offset:
Est. Count Rate:
0.1
 Order-1 Count Rate:
0.1
 Exposure Time:
15.00
 Time Remaining:

 Reqd Start Time:

 Reqd Stop Time:
Period:

 Epoch:

 Start of Period:

 End of Period:

 PS Margin:

 PE Margin:

 Max Segments:
0

Trigger Level:
DEF
 Range Switch Lvl:
DEF
 Spect Mode:
DEF
 Antico Enab:
DEF
 Width Enab:
DEF
 Width Thold:
DEF
 Uld Enab:
DEF
 Upper Lvl Disc:
DEF
Blank Enab:
DEF
 U Blank Hi:
DEF
 V Blank Hi:
DEF
 U Blank Lo:
DEF
 V Blank Lo:
DEF
 Py Shutter Pos:
DEF
 My Shutter Pos:
DEF
 Timing Mode:
N

Abstract:
A fundamental problem in current astrophysics is the equation of state of nuclear matter. Key to addressing this problem is measuring the mass-radius relation for neutron stars (NSs). We have detected an unusual feature in the spectrum of PSR J0821-4300, the compact central object (CCO) in Puppis A, that has the smallest dipole magnetic field (2.8 x 10^10 G) inferred for any young NS. This feature may provide the first detection of atomic photospheric absorption lines, allowing a model-independent, direct measurement of the mass-radius relation. Electron cyclotron resonance scattering in the small B-field is also possible, as is line emission from accretion of supernova debris. A measurement with LETGS will identify these processes and provide important new insight into condensed matter.

psci Run:
242
 Processing Date:
Aug 24 2021
 psci Directory:
/nfs/maaxnew/r3/fb/acis116e/acis116.log
OBSID:
24776
 SIM Mode:
HRC-S
 OTG Mode:
LETG
 Seq Number:
AUG0921a
 Target Name:
Histogram_I
 AO:
0
Start VCDU:
113011:032
 Start Time (UTC):
221:57382.782
 Stop Time (UTC):
221:72006.286
 Kilosecs:
14.6
 % Frames:
0.3
 # CCDs:
I5
# Frames:
4512
 # Events:
0
 Events/sec:
0
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-113.0
Parameter Block:
0x0023c024
 Window Block:
0x00039014
 # Windows:
10
 FEP Mode:
Te3x3
 BEP Mode:
EH
 Start Row:
0
 # Rows:
1024
Primary Exposure:
32
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
No
 Bias Run:
242

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