Optical variability and polarization of the Crab pulsar

Supervisor: Werner W. Zeilinger

Contact information: werner.zeilinger@univie.ac.atkieran.leschinski@univie.ac.at

Expected duration: 9 months

Project description & Goals: 

The Crab pulsar and its pulsar wind nebula are two of the most intensively studied objects in the sky. The compact remnant of SN1054, a cornerstone of high-energy astrophysics, is one of the youngest and the most energetic pulsar on the sky. Its pulsed emission has been detected throughout the electromagnetic spectrum. The pulsar and its nebula are predominantly sources of non-thermal radiation. The outstanding brightness of the Crab across the electromagnetic spectrum makes it the ideal target to investigate polarization. Time-resolved polarisation measurements offer an unique insight into the geometry of the emission regions around the pulsar. The 1.5m telescope of the Leopold-Figl Observatorium is equipped with two instruments capable of performing such observations: PICO is a combined "Lucky" imager, polarimeter and coronagraph from Onsala Space Observatory and OPTIMA a high-time resolution and high sensitivity photon counting photometer from MPE Garching. The candidate is expected to perform time series observations of the Crab pulsar with both instruments in the period November 2022 to February 2023. Depending on weather conditions, ideally 3-5 observing nights per instrument should be sufficient for the scope of the project. Data analysis will be performed with Python scripts. Most of the code is available, some adaptions of the software need to be done. One additional aspect of the observations is the calculation of the instrumental polarization for the observing setup. During the data analysis phase, light curves and polarization maps will be extracted from the observational data. The results are compared with the literature and discussed in the context of current pulsar models.

Working plan & Milestones (including final thesis):

  1. Literature review and planning of observations
  2. Observations with the instruments PICO and OPTIMA
  3. Data reduction and analysis (determination of the level of instrumental polarization)
  4. Extraction of light curves and polarization maps
  5. Comparing the results of the two instruments
  6. Discuss the results in the context of pulsar models
  7. Write the thesis

Requirements / special skills:

Basic understanding of photometric observations Understanding Python code

References:

[1] Slowikowska et al. 2009, MNRAS 397, 103 Moran et al. 2013, MNRAS 433, 256