Strategies to identify strongly lensed type Ia supernovae in Rubin LSST
PRJ 502 MS Thesis Presentation
April 15, 2024
Prajakta Mane
MS19054
Supervisors:
Prof. Surhud More, Dr. Anupreeta More
IUCAA, Pune
Local Supervisor:
Prof. Jasjeet Singh Bagla
Why strongly lensed: Time delay cosmography
accurate time delays, surface mass distribution and redshift of lens
Hubble constant with strong lensing time delays
well-constrained Hubble Constant
Hubble constant constraints from 6 lensed quasars, Wong et al., 2019
Time delay cosmography:
accurate time delays, surface mass distribution and redshift of lens
Hubble constant with strong lensing time delays
well-constrained Hubble Constant
Why SNe Ia
well-studied light curves -> more accurate time delay measurements
transient source -> improved constraints on the lens galaxy model
standard candle nature -> help overcome degeneracies
Current lensed supernova sample
PRJ 501: Recap
Quimby et al., 2014
PRJ 502
DIA Results
Template Image
Science Image
Difference Image
Template Image
Science Image
Yellow circles of radius 1": injected lensed SNe
DIA Results
Template Image
Science Image
Difference Image
Yellow circles of radius 1": injected lensed SNe
Red circles of radius 2": diaSources
DIA Results
Template Image
Science Image
Difference Image
Yellow circles of radius 1": injected lensed SNe
Red circles of radius 2": diaSources
DIA Results
Quad system
Template Image
Science Image
Difference Image
Yellow circles of radius 1": injected lensed SNe
Red circles of radius 2": diaSources
DIA Results
double system
Injected | Detected | % recovery | |
---|---|---|---|
Total | 74k | 51.5k | 70 |
Doubles | 70k | 48.3k | 70 |
Quads | 4.1k | 3.2k | 78 |
g | 310 | 260 | 83 |
r | 5.4k | 4.7k | 86 |
i | 14k | 11k | 80 |
z | 21k | 16k | 76 |
y | 34k | 20k | 58 |
Lens system level analysis:
Is there a diaSource within the radius of 3" from each lens center in each epoch?
Analysis of DIA results
Difference imaging analysis
Recovery fraction variation with injected unresolved magnitude for each band
Lens system level analysis
band | g | r | i | z | y |
single-epoch depth | 26.4 | 26.3 | 26.0 | 25.6 | 24.6 |
Yasuda et al., 2019
Difference imaging analysis
Total EUR | Total ER | |
---|---|---|
Total DUR | 99.42 | 93.40 |
Total DR | 0.56 | 6.60 |
Individual image level analysis:
How many unique diaSources were found corresponding to each lens system?
A single diaSource for entire system: Pipeline could not resolve the system (DUR): ~49k
Two or more diaSources for a system: Pipeline could resolve the system (DR): 1285
band | median seeing(") |
---|---|
g | 0.74 |
r | 0.62 |
i | 0.64 |
z | 0.59 |
y | 0.74 |
< median seeing: expected to be unresolved (EUR)
> median seeing: expected to be resolved (ER)
Aihara et al., 2017
Difference imaging analysis
Resolved fraction with respect to median seeing of each band
Individual image level analysis:
Doubles
Quads
vertical dashed line: median seeing
Summary
Color-magnitude analysis
Quimby et al. 2014
: Unlensed SNIa
: Unlensed core collapse
: Lensed SNIa
: Lensed core collapse
The redder supernovae for given i-band magnitude are more likely to be lensed SNeIa when studied for unresolved photometry on rising phase of light curve.
The black bold curve separates the lensed SNeIa from unlensed both on the rising and the falling edge of light curve for z < 2.4
Contamination from unlensed SNe is neglegible.
Contamination from CC SNe
Color-magnitude analysis
Contamination from unlensed SNe is neglegible.
Contamination from CC SNe
Color-magnitude analysis
Primary contaminants are lensed SNe Ib and Ic.
Summary of results
Ongoing work
Extra slides
Extra slides
Extra slides
The criteria hold well for the observed unlensed and lensed SNeIa.
Extra slides
Extra slides
Difference imaging analysis
Resolved fraction with respect to median seeing of each band
Individual image level analysis:
Difference imaging analysis
Resolved fraction with respect to median seeing of each band
some trend
Individual image level analysis
Difference imaging analysis
Resolved fraction with respect to median seeing of each band
no trend
Individual image level analysis
Comaparison of unlensed CC SNe CMDs from low and high redshift
PRJ 501: Recap
Quimby et al. 2014
PRJ 502