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O B S E R V A T I O N   C A T A L O G

OBSID:
25499
 Title:
Alpha Centauri and Environs         
Investigator:
Ayres
 Observer:
Ayres, Thomas
 Phone:
3034925051
 Email:
Thomas.Ayres@Colorado.edu
Target Name:
ALPHA CEN
 Sequence Number:
201477
 Instrument:
HRC-I
 Grating:
NONE
 SI Mode:
H2C_0002B
 Raster Scan:
N
 Annotated DOT:
APR2024a

Proposal Number:
23200044
 Right Ascension:
219.851
 Declination:
-60.832
 Status:
observed
 Start Date:
2024-04-27 12:29:59
Category:
STARS AND WD
 Type:
GO
 AO Cycle:
23
 Dither Flag:
Y
 Y Offset:

 Z Offset:
Est. Count Rate:
3
 Order-1 Count Rate:

 Exposure Time:
10.00
 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 tracking coronal activity cycles of late-type stars via high-contrast soft X-rays, jointly with HST to capture UV tracers. Objective is to provide fundamental observational constraints for contemporary and future studies of the underlying magnetic dynamo, whose inner workings remain elusive. The Sun's high-energy modulations play an important "Space Weather" role in our heliosphere, as do stellar counterparts for their exoplanets. 3-year time-domain campaign (joint with HST) is proposed for iconic Alpha Centauri, already followed by HRC-I since 2006. The Alpha Cen field also is rich in serendipitous sources, including flaring red dwarfs and several possibly cycling F-K stars.

Remarks:
Clarification: the spacing indicated in the Observing Time tab is meant to indicate two observations per year, about six months apart.

psci Run:
208
 Processing Date:
Jul 18 2024
 psci Directory:
/nfs/maaxnew/r3/fm/acis127b/acis127.log
OBSID:
25499
 SIM Mode:
HRC-I
 OTG Mode:
NONE
 Seq Number:
APR2024a
 Target Name:
Eventless
 AO:
0
Start VCDU:
98278:072
 Start Time (UTC):
118:45111.127
 Stop Time (UTC):
118:56727.823
 Kilosecs:
11.6
 % Frames:
100.0
 # CCDs:
I2
# Frames:
3477
 # Events:
0
 Events/sec:
0
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-118.8
Parameter Block:
0x00daa014
 Window Block:
0x00138014
 # Windows:
10
 FEP Mode:
Te3x3
 BEP Mode:
F
 Start Row:
0
 # Rows:
1024
Primary Exposure:
33
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
No
 Bias Run:
208

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