Dragonfly Pulsar analysis CristianPozo

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

- /fefs/aswg/workspace/cristian.pozo/data/PSRJ2021_3651/DL2

IRFs

- Point-like

- IRFs for each MC node and for each intensity cut

- /fefs/aswg/workspace/cristian.pozo/data/PSRJ2021_3651/IRF

DL3 data

- /fefs/aswg/workspace/cristian.pozo/data/PSRJ2021_3651/DL3

DL3 pulsar data

- Add phases using PINT-pulsar tools for LST-1 (https://github.com/alvmas/PulsarTimingAnalysis)

- Ephemeris file: /fefs/aswg/workspace/cristian.pozo/data/PSRJ2021+3651/J2021+3651_58685_60244_cube.par

- DL3 pulsar data: /fefs/aswg/workspace/cristian.pozo/data/PSRJ2021_3651/DL3_pulsar

High-level analysis

1D Spectral analysis

• Performed with gammapy-v0.20.1

energy_geometry: #Geometry on true energy and reco energy for gammapy. True energy should be larger
 real:
   emin: 0.003
   emax: 1
   units: 'TeV'
   nbinning: 40
 reco:
   emin: 0.01
   emax: 0.5
   units: 'TeV'
   nbinning: 20

spectral_points_binning 
   e_min, e_max = 0.02, 0.7
   nbins = 8 
   logspace
   sqrt_ts>1.5

• Phase Regions:

 Bkg: [0.73,1]
 P1: [0.105,0.13]
 P2: [0.57,0.615]
 P1+P2: [0.105,0.13,0.57,0.615]
 P3: None

• 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<20

• Phaseogram in different energy bins (without zd cut):

• Phaseogram in different energy bins (zd<20):

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

• Evolution of the signal in time (zd<20):

P1 LST-1 + Fermi-LAT joint fit

• • Using a PowerLaw model (without zd cut):

• • Using a PowerLaw model (zd<20):