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OBSID:
29100
 Title:
Tidal disruption events unveiled: understanding their long-term accretion with Chandra and HST
Investigator:
Nicholl
 Observer:
Nicholl, Matt
 Phone:
07858658304
 Email:
matt.nicholl@qub.ac.uk
Target Name:
AT2019qiz
 Sequence Number:
704709
 Instrument:
ACIS-S
 Grating:
NONE
 SI Mode:
TE_0057AB
 Raster Scan:
N
 Annotated DOT:
DEC0423a

Proposal Number:
24700299
 Right Ascension:
71.6578
 Declination:
-10.2264
 Status:
archived
 Start Date:
2023-12-10 14:49:06
Category:
ACTIVE GALAXIES AND QUASARS
 Type:
GO
 AO Cycle:
24
 Dither Flag:
Y
 Y Offset:
0
 Z Offset:
0
Est. Count Rate:
0.03
 Order-1 Count Rate:

 Exposure Time:
16
 Time Remaining:
16.283
 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:
Tidal disruption events (TDEs) provide a unique laboratory for studying supermassive black holes. Shortly after disruption, most TDEs are 'veiled': emitting mainly UV/optical while X-ray signs of accretion are obscured. However by >~3 years, the stellar debris should settle into a thin, unobscured disk, brightest in X-rays and UV. We propose to observe 3 very nearby and well-studied TDEs at late phases using Chandra and HST. Only previous 1 TDE (and no veiled TDEs) have high S/N X-ray data at late times. Covering the SED peak with X-ray+UV reveals (1) the evolution of the accretion rate, and whether embedded accretion powered the optical flare; (2) the dominant energy release mechanism in the disk; and (3) fundamental disk parameters such as masses and possibly spin.

Remarks:
Joint HST data requested if possible within 30 days of Chandra data, however this can be relaxed if it leads to complications in scheduling

psci Run:
104
 Processing Date:
Jan 3 2024
 psci Directory:
/nfs/maaxnew/r3/fl/acis126b/acis126.log
OBSID:
29100
 SIM Mode:
ACIS-S
 OTG Mode:
NONE
 Seq Number:
704709
 Target Name:
AT2019qiz
 AO:
24
Start VCDU:
125611:000
 Start Time (UTC):
344:54157.615
 Stop Time (UTC):
344:70451.553
 Kilosecs:
16.3
 % Frames:
100.0
 # CCDs:
S2
# Frames:
5358
 # Events:
164815
 Events/sec:
10
 PSCI errors:
0
 % drops:
0.0
 Bias Errs:
0
 FP Temp:
-111.3
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:
104

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