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OBSID:
22661
 Title:
Cycles and the Seven Dwarfs         
Investigator:
Ayres
 Observer:
Ayres, Thomas
 Phone:
3034925051
 Email:
Thomas.Ayres@Colorado.edu
Target Name:
XI BOO
 Sequence Number:
201318
 Instrument:
HRC-I
 Grating:
NONE
 SI Mode:
H2C_0001B
 Raster Scan:
N
 Annotated DOT:
JUL1023b

Proposal Number:
21200230
 Right Ascension:
222.848
 Declination:
19.1001
 Status:
archived
 Start Date:
2023-07-14 11:08:14
Category:
STARS AND WD
 Type:
GO
 AO Cycle:
21
 Dither Flag:
Y
 Y Offset:

 Z Offset:
Est. Count Rate:
2
 Order-1 Count Rate:

 Exposure Time:
5.00
 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:
EDGE
 U Blank Hi:
119
 V Blank Hi:
119
 U Blank Lo:
69
 V Blank Lo:
69
 Py Shutter Pos:
DEF
 My Shutter Pos:
DEF
 Timing Mode:
N

Abstract:
Chandra has been following magnetic heartbeats of late-type stars via high-contrast coronal X-rays. Goal is to provide fundamental observational constraints for contemporary and future studies of underlying magnetic Dynamo, whose internal workings remain elusive. The Sun's high-energy modulations play important "Space Weather" role in our heliosphere, as do stellar counterparts for their exoplanets. 3-year time series (joint with HST) is proposed for promising new candidates Xi Boo (G8V+K4) and 70 Oph (K0V+K5V), adding four more dwarfs to the three in current "Cycles." Key question involves origin of diverging branches in rotational period vs. cycle duration, where Sun's iconic 11-yr example sits in the middle, possibly in a transitional state.

Remarks:
This is a Preference: 1st observation could be scheduled early-Apr 2020, and 2nd observation in early-Sep 2020 (both windows at unconstrained pitch angles); repeat in subsequent 2 Cycles.

psci Run:
418
 Processing Date:
Jul 25 2023
 psci Directory:
/nfs/maaxnew/r3/fj/acis124e/acis124.log
OBSID:
22661
 SIM Mode:
HRC-I
 OTG Mode:
NONE
 Seq Number:
JUL1023b
 Target Name:
Histogram_I
 AO:
0
Start VCDU:
125931:072
 Start Time (UTC):
195:40359.976
 Stop Time (UTC):
195:47192.408
 Kilosecs:
6.8
 % Frames:
0.4
 # CCDs:
I2
# Frames:
2045
 # Events:
0
 Events/sec:
0
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-115.4
Parameter Block:
0x00d96014
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te3x3
 BEP Mode:
EH
 Start Row:
0
 # Rows:
1024
Primary Exposure:
33
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
No
 Bias Run:
418

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