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OBSID:
27454
 Title:
Calibration of the quasar Hubble diagram with z <~ 0.7 quasars as CATs  
Investigator:
Civano
 Observer:
Civano, Francesca
 Phone:
617-496-1887
 Email:
francesca.m.civano@nasa.gov
Target Name:
SDSSJ114804.00+453428.2
 Sequence Number:
704866
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_0057A
 Raster Scan:
N
 Annotated DOT:
SEP2622b

Proposal Number:
20701058
 Right Ascension:
177.017
 Declination:
45.5745
 Status:
archived
 Start Date:
2022-09-29 07:36:25
Category:
ACTIVE GALAXIES AND QUASARS
 Type:
CCT
 AO Cycle:
20
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.035052
 Order-1 Count Rate:

 Exposure Time:
15
 Time Remaining:
14.943
 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:
Quasars are among the most luminous sources in the sky and as such can be detected up to very high redshifts (z=7.54). For these reasons, scientists have long chased the possibility of using quasars to constrain cosmological models in a completely unexplored redshift range (z>1.4, beyond which Supernovae (SN) are rarely detected). Despite several attempts, most of the proposed methods are affected by a high dispersion in the observational relations used, preventing high precision distance measurements. A new method, recently proposed by Risaliti and Lusso 2015, overcomes this difficulty by taking advantage of the very large statistic provided by the quasar surveys currently available. Building upon this result and the latest improvements about it, the goal of this CAT project is to increase the sample of low-z (z<0.7) quasars with good quality X-ray data from pointed observations to decrease the dispersion in the quasar Hubble diagram and calibrate a zero-point for it.

Remarks:
N/A

psci Run:
307
 Processing Date:
Oct 17 2022
 psci Directory:
/nfs/maaxnew/r3/fg/acis121e/acis121.log
OBSID:
27454
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
704866
 Target Name:
SDSSJ114804.00+
 AO:
20
Start VCDU:
106834:040
 Start Time (UTC):
272:28778.056
 Stop Time (UTC):
272:43733.762
 Kilosecs:
15.0
 % Frames:
100.0
 # CCDs:
S2
# Frames:
4918
 # Events:
201632
 Events/sec:
13
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-112.3
Parameter Block:
0x0057b034
 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?:
No
 Trickle?:
Yes
 Bias Run:
305

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