Dragonfly Pulsar analysis CristianPozo
Contents
- 1 General information
- 2 People involved in this analysis (LST-1 and new Fermi-LAT analysis)
- 3 Run selection
- 4 DL1 data
- 5 DL2 data
- 6 DL3 data
- 7 DL3 pulsar data
- 8 High-level analysis
- 9 Results
General information
- Name of the source: Dragonfly Pulsar (PSRJ2021+3651)
- Brief description of the source:
- - Object type : Pulsar
- - RA, Dec in deg (ICRS): 305.27252, 36.85126
People involved in this analysis (LST-1 and new Fermi-LAT analysis)
- Cristian Pozo González
- Alvaro Mas-Aguilar
- Ruben Lopez-Coto
- Daniel Morcuende
Run selection
- Run selection with the use of the notebook from Abelardo Moralejo [1]
- Atmospheric transmission extracted from ELOG
- In total 48 runs selected, obstime 13.51 hours
- Summary of selection cuts:
- - Zenith < 70 deg and Zenith < 20 deg
- - elapsed_time > 2 min
- - transmission_cut > 0.60
- - pedestal charge std dev < 1.9 p.e.
- - Cosmic rate > 3000 ev/s
- - Cosmic rate( > 10 p.e.) > 25-15 ev/s (depends on zd)
- - Cosmic rate( > 30 p.e.) > 3-4 ev/s (depends on zd)
- Number of runs with zenith < 70 deg (% is w.r.t. those in Sky region & zenith range):
+ In the requested Sky region and range of dates: 132 + zenith in requested range: 132 + NSB in requested range: 131 (99.2%) + FF and pedestal interleaved events are present: 130 (98.5%) + Stable pointing: 129 (97.7%) + dR/dI fit P-value ok: 128 (97.0%) + dR/dI LS periodogram ok: 127 (96.2%) + dR/dI index ok: 121 (91.7%) + dR/dI rate ok: 48 (36.4%) + intensity threshold ok: 48 (36.4%)
Note: about 64% of all *dark-night* observations within ZD<80 deg fulfill all quality cuts. (in the stable, good-quality period 2022-11-18 - 2023-02-14, 92% of *dark-night* observations within ZD<80 deg do).
- List of selected runs (Zenith < 70 deg):
1 : 2022-06-28 : [8948 8949 8950 8951 8952 8953 8954 8955 8956 8957 8958 8959] 2 : 2022-06-29 : [8980 8982 8983 8985 8986 8987] 3 : 2023-05-16 : [13062 13063 13064 13066 13067] 4 : 2023-05-18 : [13096 13097 13098 13099] 5 : 2023-06-22 : [13519 13520 13521 13522] 6 : 2023-06-25 : [13588 13589 13590 13591] 7 : 2023-10-05 : [14910] 8 : 2023-10-06 : [14918 14919 14920 14921 14922 14923 14924] 9 : 2023-11-13 : [15489 15490 15491 15495 15497]
- Number of runs with zenith < 20 deg (% is w.r.t. those in Sky region & zenith range):
+ In the requested Sky region and range of dates: 132 + zenith in requested range: 77 + NSB in requested range: 76 (98.7%) + FF and pedestal interleaved events are present: 75 (97.4%) + Stable pointing: 74 (96.1%) + dR/dI fit P-value ok: 73 (94.8%) + dR/dI LS periodogram ok: 73 (94.8%) + dR/dI index ok: 72 (93.5%) + dR/dI rate ok: 31 (40.3%) + intensity threshold ok: 31 (40.3%)
Note: about 64% of all *dark-night* observations within ZD<80 deg fulfill all quality cuts. (in the stable, good-quality period 2022-11-18 - 2023-02-14, 92% of *dark-night* observations within ZD<80 deg do).
- List of selected runs (Zenith < 20 deg):
1 : 2022-06-28 : [8951 8952 8953 8954 8955 8956 8957 8958 8959] 2 : 2022-06-29 : [8980 8982 8983 8985 8986 8987] 3 : 2023-05-16 : [13066 13067] 4 : 2023-05-18 : [13098 13099] 5 : 2023-06-22 : [13520 13521 13522] 6 : 2023-06-25 : [13588 13589 13590 13591] 7 : 2023-10-05 : [14910] 8 : 2023-10-06 : [14918 14919 14920 14921]
DL1 data
- - DL1a files produced by LSTOSA (lstchain v0.9.9)
- - lstchain v0.9 tailcut8-4
- - /fefs/aswg/data/real/DL1/{date}/v0.9/tailcut84/
DL2 data
- -
IRFs
- - Point-like
- - IRFs for each MC node and for each intensity cut
- -
DL3 data
- -
DL3 pulsar data
- - Add phases using PINT-pulsar tools for LST-1 (https://github.com/alvmas/PulsarTimingAnalysis)
- - Ephemeris file:
- - DL3 pulsar data:
High-level analysis
1D Spectral analysis
- Performed with gammapy-v0.20.1
energy_axis = MapAxis.from_energy_bounds( 0.01, 10, nbin=40, per_decade=False, unit="TeV", name="energy" ) energy_axis_true = MapAxis.from_energy_bounds( 0.05, 100, nbin=100, per_decade=False, unit="TeV", name="energy_true" )
spectral_points_binning e_min, e_max = 0.02, 0.7 nbins = 8 logspace sqrt_ts>1.5
- Phase Regions:
Bkg: [0.52,0.87] P1: [0,0.026,0.983,1] P2: [0.377,0.422] P1+P2: [0,0.026,0.377,0.422, 0.983,1] P3: [0.08,0.24]
- Spectral fitting of stacked LST dataset
- Performed for point-like assumption
- Stacked analysis
- LST-1 data alone: Power-law spectral model
- Fermi + LST-1 data: Power-Law Spectral Model, ExponentialCutOff, LogParabola
Results
Phaseogram
- Phaseogram with all data
- Phaseogram with zd<35
- Phaseogram with zd>35
- Phaseogram in different energy bins:
- Evolution of the signal in time (without zd cut):
- Fitting results
- P1/P2 differential ratio (with Fermi-LAT). Until 200 GeV due to large uncertainties
- P1/P2 integral ratio (with Fermi-LAT).
LST-1 only fit and SED (zd<50)
- P1
- P2
P1 LST-1 + Fermi-LAT joint fit
- Using a SubExponentialCutOffPL model:
Total stat: -2logL = 32.56
- Using a SmoothBrokenPowerLaw model
Total stat: -2logL = 24.44
- P1 for E>10 GeV:
- Using a LogParabola model
Total stat: -2logL = 7.34
- Using a PowerLaw model
Total stat: -2logL = 7.83
P2 LST-1 + Fermi-LAT joint fit
- Using a SubExponentialCutOffPL model:
Total stat: -2logL = 51.40
- Using a SmoothBrokenPowerLaw model
Total stat: -2logL = 34.74
- P2 for E>10 GeV:
- Using a LogParabola model
Total stat: -2logL = 17.85
- Using a PowerLaw model
Total stat: -2logL = 19.35
LST-1+ Fermi-LAT energy calibration
- P1 in left and P2 in right (Using SmoothBrokenPowerLaw model in all energy range)
- P1 in left and P2 in right (Using PowerLaw model at E>10 GeV)
In all the cases the energy factor that minimize the chi2 value is below 5%
Lightcurve
Systematics tests
Phaseogram and SED for different samples
- Phaseogram Before August 2021
sign(P1)/sqrt(Tobs) = 0.856 h^(-1/2)
sign(P2)/sqrt(Tobs) = 1.059 h^(-1/2)
- Phaseogram After August 2021
sign(P1)/sqrt(Tobs) = 1.063 h^(-1/2)
sign(P2)/sqrt(Tobs) = 1.183 h^(-1/2)
- SED for P1:
Difference in spectral index of ~10% and flux 60% (lacking some statistics for first sample)
- SED for P2:
Difference in spectral index of ~2% and flux of 15%
Phaseogram and SED with different efficiencies
- P1 SED:
Relative maximum error of 3.07% in spectral index and 35.4% in flux.
- P1 SED:
Relative maximum error of 7.36% in spectral index and 29.2% in flux.
Effect on SED due to shift on MC true energy =
- P1:
Relative maximum error of 1.01% in spectral index and 24.9% in flux.
- P2:
Relative maximum error of 0.45% in spectral index and 16.4% in flux.
Final uncertainties
- P1:
- P2: