A Cyclic Spectroscopy Scintillation Study of PSR B1937+21 I. Demonstration of Improved Scintillometry

Abstract

We use cyclic spectroscopy to perform high frequency-resolution analyses of multi-hour baseband Arecibo observations of the millisecond pulsar PSR B1937+21. This technique allows for the examination of scintillation features in far greater detail than is otherwise possible under most pulsar timing array observing setups. We measure scintillation bandwidths and timescales in each of eight subbands across a 200 MHz observing band in each observation. Through these measurements we obtain intra-epoch estimates of the frequency scalings for scintillation bandwidth and timescale.Thanks to our high frequency resolution and the narrow scintles of this pulsar, we resolve scintillation arcs in the secondary spectra due to the increased Nyquist limit, which would not have been resolved at the same observing frequency with a traditional filterbank spectrum using NANOGrav's current time and frequency resolutions, and the frequency-dependent evolution of scintillation arc features within individual observations. We observe the dimming of prominent arc features at higher frequencies, possibly due to a combination of decreasing flux density and the frequency dependence of the plasma refractive index of the interstellar medium. We also find agreement with arc curvature frequency dependence predicted by Stinebring et al. (2001) in some epochs. Thanks to the frequency resolution improvement provided by cyclic spectroscopy, these results show strong promise for future such analyses with millisecond pulsars, particularly for pulsar timing arrays, where such techniques can allow for detailed studies of the interstellar medium in highly scattered pulsars without sacrificing the timing resolution that is crucial to their gravitational wave detection efforts.

Accepted to ApJ

References in corpus (15)

• The NumPy array: a structure for efficient numerical computation
• The NANOGrav 15-year Data Set: Observations and Timing of 68 Millisecond Pulsars
• The NANOGrav 15-Year Data Set: Detector Characterization and Noise Budget
• The second data release from the European Pulsar Timing Array II. Customised pulsar noise models for spatially correlated gravitational waves
• A Scintillation Arc Survey of 22 Pulsars with Low to Moderate Dispersion Measures
• Double-lens Scintillometry: The variable scintillation of pulsar B1508+55
• Scattering study of Pulsars below 100 MHz using LWA1
• Long-term scintillation studies of EPTA pulsars. I. Observations and basic results
• Millisecond Pulsar Scintillation Studies with LOFAR: Initial Results
• Multi-frequency scatter broadening evolution of pulsars - II. Scatter broadening of nearby pulsars
• Variable Scintillation Arcs of Millisecond Pulsars observed with the Large European Array for Pulsars
• Pulsar Double-lensing Sheds Light on the Origin of Extreme Scattering Events
• Analysis of Multi-Hour Continuous Observations of Seven Millisecond Pulsars
• Scattering Delay Mitigation in High Accuracy Pulsar Timing: Cyclic Spectroscopy Techniques
• A Simultaneous Dual-Frequency Scintillation Arc Survey of Six Bright Canonical Pulsars Using the Upgraded Giant Metrewave Radio Telescope

Cited by in corpus (4)

• Exploring pulsar timing precision: A comparative study of polarization calibration methods for NANOGrav data from the Green Bank Telescope
• Pulsar Cyclic Spectroscopy in the Partial-Deconvolution Regime: Benefits & Limitations
• The NANOGrav 15 yr Data Set: Customized Chromatic Noise Models
• Constraining Scattering Medium Geometry with Cyclic Spectroscopy