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OBSID:
23771
 Title:
A CHANDRA LOOK AT VARIABILITY-SELECTED LOW-MASS AGN CANDIDATES   
Investigator:
Baldassare
 Observer:
Baldassare, Vivienne
 Phone:
6313387403
 Email:
vivienne.baldassare@wsu.edu
Target Name:
NSA 67333
 Sequence Number:
704183
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_0065AB
 Raster Scan:
N
 Annotated DOT:
MAR0921a

Proposal Number:
22700333
 Right Ascension:
186.7
 Declination:
7.67154
 Status:
archived
 Start Date:
2021-03-14 18:13:37
Category:
ACTIVE GALAXIES AND QUASARS
 Type:
GO
 AO Cycle:
22
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.02478
 Order-1 Count Rate:

 Exposure Time:
1
 Time Remaining:
1.066
 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
 Dropped Chip Count:
0
 Optional Chips:
I3 S2 S4
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:
The population of massive black holes (BHs) in present day low-mass galaxies is an important constraint for models of black hole formation and growth. However, these systems are generally difficult to find. We have recently identified a population of low-mass galaxies (Mstar=5x10^7 - 5x10^9 Msun) with long-term optical photometric variability consistent with an active galactic nucleus (AGN). These systems tend to lack optical spectroscopic AGN signatures, indicating they may be AGN missed by standard selection techniques. We propose joint Chandra and HST observations of 9 nearby (z<0.02) low-mass galaxies with AGN-like variability to validate this selection technique, study accretion properties, and characterize host galaxies.

psci Run:
5
 Processing Date:
Apr 1 2021
 psci Directory:
/nfs/maaxnew/r3/fa/acis115a/acis115.log
OBSID:
23771
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
704183
 Target Name:
NSA_67333
 AO:
22
Start VCDU:
116634:104
 Start Time (UTC):
073:66738.213
 Stop Time (UTC):
073:67815.583
 Kilosecs:
1.1
 % Frames:
100.0
 # CCDs:
I4
# Frames:
343
 # Events:
36067
 Events/sec:
33
 PSCI errors:
0
 % drops:
0.3
 Bias Errs:
0
 FP Temp:
-118.1
Parameter Block:
0x0065a034
 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:
5

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