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OBSID:
26355
 Title:
X-ray Window into Internal Structure of the Cold Gas in Dense Molecular Clouds 
Investigator:
Kraft
 Observer:
Vikhlinin, Alexey
 Phone:
857-928-6401
 Email:
avikhlinin@cfa.harvard.edu
Target Name:
CMZ Molecular Cloud
 Sequence Number:
901824
 Instrument:
ACIS-I
 Grating:
NONE
 SI Mode:
TE_006E6B
 Raster Scan:
N
 Annotated DOT:
MAR1122a

Proposal Number:
22910683
 Right Ascension:
266.543
 Declination:
-28.8853
 Status:
archived
 Start Date:
2022-03-12 06:45:41
Category:
GALACTIC DIFFUSE EMISSION AND SURVEYS
 Type:
GTO
 AO Cycle:
22
 Dither Flag:
Y
 Y Offset:
2
 Z Offset:
2
Est. Count Rate:
1
 Order-1 Count Rate:

 Exposure Time:
17
 Time Remaining:
16.898
 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:
Dense clouds in the Central Molecular Zone are subject to the most extreme and dynamic environment in the Milky Way. They are ideal laboratories to study, in action, all the key processes that operate in a typical molecular cloud and determine its fragmentation and star formation. We are extremely fortunate to have an independent and exquisite tool for their studies - the X-ray reflection of the past SgrA* outbursts. A deep Chandra observation can be used to measure the 3D structure of the clouds down to ~ the pre-Solar nebula size scales (<~ 0.1 pc). This will provide a crucial observational input to models of cloud evolution and fragmentation and will link these processes to the natural scale of proto-star and proto-planetary nebula formation.

psci Run:
137
 Processing Date:
Mar 21 2022
 psci Directory:
/nfs/maaxnew/r3/fe/acis119b/acis119.log
OBSID:
26355
 SIM Mode:
ACIS-I
 OTG Mode:
NONE
 Seq Number:
901824
 Target Name:
CMZ_Molecular_C
 AO:
22
Start VCDU:
22998:120
 Start Time (UTC):
071:25562.852
 Stop Time (UTC):
071:42474.087
 Kilosecs:
16.9
 % Frames:
100.0
 # CCDs:
I4
# Frames:
5384
 # Events:
546442
 Events/sec:
32
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
1
 FP Temp:
-112.9
Parameter Block:
0x006e6034
 Window Block:
-
 # Windows:
0
 FEP Mode:
Te5x5
 BEP Mode:
F
 Start Row:
0
 # Rows:
1024
Primary Exposure:
31
 Secondary Exposure:
0
 Duty Cycle:
0
 Summing?:
No
 Bias?:
Yes
 Trickle?:
Yes
 Bias Run:
137

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