| Name: Debabrata Deb |
| Affiliation: Centre for Space Research, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa |
| Conference ID: ASI2026_600 |
| Title: Frequency-Resolved Template Generation and Optimal Subbanding for Precision Pulsar Timing |
| Abstract Type: Poster |
| Abstract Category: High Energy Phenomena, Fundamental Physics and Astronomy |
| Author(s) and Co-Author(s) with Affiliation: Debabrata Deb(Centre for Space Research, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa) |
| Abstract: We present a robust methodology for constructing high-fidelity, frequency-resolved pulsar templates and optimally determining the number of sub-bands required for precision timing at uGMRT frequencies. This methodology is developed and rigorously tested on realistic simulated data generated using our comprehensive pulsar signal simulation framework. Low-frequency timing is challenged by strong frequency-dependent profile evolution and epoch-varying dispersion measure (DM) fluctuations, both of which bias template alignment and DM estimation. Our procedure first identifies a suitable high-S/N template epoch, applies bandshape equalisation to remove instrumental amplitude distortions while preserving intrinsic spectral structure, and then generates noise-suppressed frequency-resolved templates using optimally selected wavelet smoothing. These templates are consistently aligned using a fiducial DM obtained through an iterative timing procedure, and the optimal frequency resolution is determined statistically by evaluating the residuals of adjacent subband profiles and testing their Gaussianity across representative epochs. While most existing PTA collaborations currently employ frequency-averaged templates and subsequently introduce ad-hoc frequency-dependent (FD) parameters to account for chromatic profile evolution during timing analysis, the InPTA consortium uniquely implements frequency-resolved sub-banded templates, thereby modelling the intrinsic evolution at the template level itself. Validation using realistic simulations confirms that our methodology minimises chromatic timing biases and enhances DM stability, enabling reproducible and high-precision frequency-resolved pulsar timing.
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