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OBSID:
27852
 Title:
Stellar activity with TESS and Chandra       
Investigator:
G�nther
 Observer:
Günther, Hans
 Phone:
6172538008
 Email:
hgunther@mit.edu
Target Name:
1RXS J172100.9-210640
 Sequence Number:
201623
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_0057AB
 Raster Scan:
N
 Annotated DOT:
MAY2223a

Proposal Number:
20201077
 Right Ascension:
260.252
 Declination:
-21.1129
 Status:
archived
 Start Date:
2023-05-27 03:44:40
Category:
STARS AND WD
 Type:
CCT
 AO Cycle:
20
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.061
 Order-1 Count Rate:

 Exposure Time:
20
 Time Remaining:
20.084
 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
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:
All cool stars show magnetic activity, and X-ray emission is the hallmark of this activity. Gaining an understanding of activity aids us in answering fundamental questions about stellar astrophysics and in determining the impact of activity on the exoplanets that orbit these stars. Stellar activity is driven by magnetic fields, which are ultimately powered by convection and stellar rotation. However, the resulting dynamo properties heavily depend on the stellar interior structure and are far from being understood. X-ray radiation can evaporate exoplanet atmospheres and damage organic materials on the planetary surface, reducing the probability that life can form or be sustained, but also provides an important source of energy for prebiotic chemical reactions. Over the next two years, the TESS mission will deliver a catalog of the closest exoplanets, along with rotation periods and activity diagnostics for millions of stars, whether or not they have a planet. We propose to include all cool stars that are TESS targets and bright enough for Chandra observations, as determined by their detection and flux in the ROSAT all-sky survey (RASS), to the list of Chandra Cool Targets.

Remarks:
N/A

psci Run:
219
 Processing Date:
Jun 5 2023
 psci Directory:
/nfs/maaxnew/r3/fj/acis124c/acis124.log
OBSID:
27852
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
201623
 Target Name:
2RXS_J172100.8-
 AO:
20
Start VCDU:
129765:112
 Start Time (UTC):
147:14588.744
 Stop Time (UTC):
147:34683.851
 Kilosecs:
20.1
 % Frames:
100.0
 # CCDs:
S2
# Frames:
6608
 # Events:
248101
 Events/sec:
12
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-116.4
Parameter Block:
0x0057a034
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te5x5
 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:
219

pgf@space.mit.edu Thu Apr 3 20:00:53 EST 2025