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OBSID:
24991
 Title:
Fraternal or Identical? The Magnetic Properties of M Dwarf Twins   
Investigator:
Osten
 Observer:
Osten, Rachel
 Phone:
4103384762
 Email:
osten@stsci.edu
Target Name:
KX ComAB
 Sequence Number:
201380
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_00A04B
 Raster Scan:
N
 Annotated DOT:
MAR1521a

Proposal Number:
22200260
 Right Ascension:
194.22
 Declination:
23.4974
 Status:
archived
 Start Date:
2021-03-15 18:45:29
Category:
STARS AND WD
 Type:
GO
 AO Cycle:
22
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.052
 Order-1 Count Rate:

 Exposure Time:
17
 Time Remaining:
17.091
 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:
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:
We propose for 188 ksec of observing time on Chandra to monitor X-ray activity on 4 pairs of virtually ``identical twin'' M dwarfs. These twin wide binaries are comprised of stars with nearly identical masses, ages, and compositions. Evolutionary models and conventional thinking suggest that such sets of twin stars should evolve nearly co-equally, resulting in similar levels of magnetic activity. These Chandra data will be used in concert with optical monitoring that provides information about short-term flaring, medium-term rotation periods, and long-term stellar spot cycles, which can then be correlated with X-ray activity.

Remarks:
position given is that of KX Com A; separation is 7.8". total field count rate estimated by searching RASS for sources within 4', adding count rates, and using the same multiplier to convert RASS count rate to Chandra Cycle 22 count rate.

psci Run:
10
 Processing Date:
Apr 1 2021
 psci Directory:
/nfs/maaxnew/r3/fa/acis115a/acis115.log
OBSID:
24991
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
201380
 Target Name:
KX_ComAB
 AO:
22
Start VCDU:
119337:120
 Start Time (UTC):
074:68589.585
 Stop Time (UTC):
074:85692.280
 Kilosecs:
17.1
 % Frames:
100.0
 # CCDs:
S1
# Frames:
5624
 # Events:
163471
 Events/sec:
9
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-117.6
Parameter Block:
0x00a04014
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te3x3
 BEP Mode:
F
 Start Row:
0
 # Rows:
1024
Primary Exposure:
30
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
10

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