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O B S E R V A T I O N   C A T A L O G

OBSID:
28929
 Title:
Chandra-NuSTAR synergy in the NuSTAR serendipitous survey    
Investigator:
Alexander
 Observer:
Alexander, David
 Phone:
44 191 3343594
 Email:
d.m.alexander@dur.ac.uk
Target Name:
Ark120
 Sequence Number:
705127
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_0057AB
 Raster Scan:
N
 Annotated DOT:
SEP2523a

Proposal Number:
20701059
 Right Ascension:
79.1107
 Declination:
-0.204688
 Status:
archived
 Start Date:
2023-09-29 08:44:44
Category:
ACTIVE GALAXIES AND QUASARS
 Type:
CCT
 AO Cycle:
20
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.1
 Order-1 Count Rate:

 Exposure Time:
10
 Time Remaining:
10.08
 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:
A great breakthrough in resolving the peak of the cosmic X-ray background (CXB) is NuSTAR. The NuSTAR extragalactic survey has resolved ~35% of the CXB at the >10 keV peak, provided the first measurements of the >10 keV AGN luminosity function at z>0.1, and identified extreme heavily obscured AGNs. The NuSTAR serendipitous survey is the largest component of the extragalactic survey program and provides the majority of the (~75-80%) NuSTAR-detected sources. Through a combination of deep and shallow wide-area coverage it fills out the X-ray luminosity-redshift plane of AGN and detects intrinsically rare source populations. However, the NuSTAR data alone are insufficient to fully understand the physical properties of the NuSTAR sources and Chandra CATS observations are required to (i) provide reliable sub-arcsec optical counterpart identification for spectroscopic observations to obtain redshifts and identify Galactic sources and (ii) broad-band X-ray spectral to characterize the X-ray emission of the NuSTAR sources down to ~0.5-3 keV, where NuSTAR has no sensitivity. The Chandra CATS observations will allow for (i) the robust identification of optical counterparts, (ii) the characterization of the 0.5-24 keV spectra, (iii) the detection of multiple Chandra counterparts in spatially complex systems and crowded fields, (iv) a broad suite of analyses to constrain the properties and evolution of AGN at >10 keV, and (v) long-term (>1 year timescale) X-ray variability analyses for the NuSTAR sources with existing X-ray coverage. The Chandra CATS target list includes all of the NuSTAR sources that lie within 40 degrees of the ecliptic within the serendipitous survey to date.

Remarks:
N/A

psci Run:
273
 Processing Date:
Oct 24 2023
 psci Directory:
/nfs/maaxnew/r3/fk/acis125d/acis125.log
OBSID:
28929
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
705127
 Target Name:
Ark120_s3
 AO:
20
Start VCDU:
66361:104
 Start Time (UTC):
272:32422.778
 Stop Time (UTC):
272:42516.007
 Kilosecs:
10.1
 % Frames:
100.0
 # CCDs:
S2
# Frames:
3319
 # Events:
121793
 Events/sec:
12
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-109.1
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:
273

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