Dragonfly Pulsar analysis CristianPozo

From my_wiki
Jump to: navigation, search

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 all 0.7.png

  • Phaseogram with zd<35

Phaseogram low50.png

  • Phaseogram with zd>35

Phaseogram above50.png

  • Phaseogram in different energy bins:

Phaseogram bin1 1.png Phaseogram bin2 1.png Phaseogram bin3 1.png Phaseogram bin4 1.png Phaseogram bin5 1.png Phaseogram bin6 1.png Phaseogram bin7 1.png

  • Evolution of the signal in time (without zd cut):

Time evolution lst.png

  • Fitting results
  • P1/P2 differential ratio (with Fermi-LAT). Until 200 GeV due to large uncertainties

P1p2 differential 2.png

  • P1/P2 integral ratio (with Fermi-LAT).

P1p2 ratio integral 2.png

LST-1 only fit and SED (zd<50)

  • P1

SED P1 1.png LST fit only P1 fine bin fermi.png LST fit only P1 fine wide fermi.png

Fitting sed p1.png


  • P2

SED p2 1.png LST fit only P2 fine bin fermi.png LST fit only P2 wide bin fermi.png

Fitting sed p2.png

P1 LST-1 + Fermi-LAT joint fit

    • Using a SubExponentialCutOffPL model:

P1 exponential model 3.png Exponential result fit P1.png

Total stat: -2logL = 32.56

    • Using a SmoothBrokenPowerLaw model

SmoothBrokenPL P1 2.png SmoothBPL results fit P1.png

Total stat: -2logL = 24.44

  • P1 for E>10 GeV:
    • Using a LogParabola model

P1 logParabolaModel 2.png LogParabola results fit P1.png

Total stat: -2logL = 7.34

    • Using a PowerLaw model

P1 PLmodel 2.png PL results fit P1.png

Total stat: -2logL = 7.83

P2 LST-1 + Fermi-LAT joint fit

    • Using a SubExponentialCutOffPL model:

P2 Exponential model.png Exponential results fit P2.png

Total stat: -2logL = 51.40

    • Using a SmoothBrokenPowerLaw model

SmoothBrokenPL P2.png SmoothBPL results fit P2.png

Total stat: -2logL = 34.74


  • P2 for E>10 GeV:
    • Using a LogParabola model

P2 logParabolaModel.png LogParabola results fit P2.png

Total stat: -2logL = 17.85

    • Using a PowerLaw model

P2 PLmodel.png PL results fit P2.png

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)

Energy factor fermi LST P1 3.png Energy factor LST fermi P2 3.png

  • P1 in left and P2 in right (Using PowerLaw model at E>10 GeV)

Energy factor fermi LST P1 PL 3.png Energy factor LST fermi P2 PL 3.png

In all the cases the energy factor that minimize the chi2 value is below 5%

Lightcurve

Lightcurve.png Lightcurve together.png

Systematics tests

Phaseogram and SED for different samples

  • Phaseogram Before August 2021

Histo preAug.png


sign(P1)/sqrt(Tobs) = 0.856 h^(-1/2)

sign(P2)/sqrt(Tobs) = 1.059 h^(-1/2)


  • Phaseogram After August 2021

Histo posAug.png

sign(P1)/sqrt(Tobs) = 1.063 h^(-1/2)

sign(P2)/sqrt(Tobs) = 1.183 h^(-1/2)

  • SED for P1:

Spectra P1 bothsamples.png

Difference in spectral index of ~10% and flux 60% (lacking some statistics for first sample)


  • SED for P2:

Spectra P2 bothsamples.png

Difference in spectral index of ~2% and flux of 15%

Phaseogram and SED with different efficiencies

Phaseogram different efficiencies.png

  • P1 SED:

SED different efficiencies.png Relative maximum error of 3.07% in spectral index and 35.4% in flux.

  • P1 SED:

SED different efficiencies P2.png 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:

P1 energy factor SED 2.png

Relative maximum error of 1.01% in spectral index and 24.9% in flux.

    • P2:

Energy factor LST P2.png

Relative maximum error of 0.45% in spectral index and 16.4% in flux.

Final uncertainties

    • P1:

Relative error index P1.png Relative error flux P1.png Total uncertainty P1.png

    • P2:

Relative error index P2.png Relative error flux P2.png Total uncertainty P2.png