pinta: The uGMRT data processing pipeline for the Indian Pulsar Timing Array

Abstract

We introduce pinta, a pipeline for reducing the upgraded Giant Metre-wave Radio Telescope (uGMRT) raw pulsar timing data, developed for the Indian Pulsar Timing Array experiment. We provide a detailed description of the workflow and usage of pinta, as well as its computational performance and RFI mitigation characteristics. We also discuss a novel and independent determination of the relative time offsets between the different back-end modes of uGMRT and the interpretation of the uGMRT observation frequency settings and their agreement with results obtained from engineering tests. Further, we demonstrate the capability of pinta to generate data products which can produce high-precision TOAs using PSR J1909 $-$ 3744 as an example. These results are crucial for performing precision pulsar timing with the uGMRT.

Multiband Detection of Repeating FRB 20180916B

“…We took 40 minute scans of the source followed by observation of 3C48 in between for phase adjusments; this can be seen as gaps between scans in Figure 1. The high-time-resolution filterbank data products for each scan were rid of any bright narrowband and broadband (zero DM) interference using gptool (Susobhanan et al 2021) before converting them to SIGPROC (Lorimer 2011) formatted standard filterbank files.…”

Pulsar-timing measurement of the circular polarization of the stochastic gravitational-wave background

“…Over the last decade, PTA consortia have been gathering increasingly precise timing data and are beginning to dip into an astrophysically interesting region of the SGWB parameter space. The prospect of detection in the near future and the expansion of both telescope-centered programs [36,37] and new PTAs [38] motivates us to consider what are the next targets after an isotropic background is measured.…”

The Indian Pulsar Timing Array: First data release

“…The channelised time series data generated by the uGMRT were recorded using the GMRT Wideband Backend (GWB: Reddy et al 2017) in a binary raw data format, along with the timestamp at the start of the observation in a separate ASCII file. We used a pipeline named pinta (Susobhanan et al 2021) to convert these raw data files into partially folded PSRFITS archives, which can be further analyszed using popular pulsar softwares such as PSRCHIVE (Hotan, Van Straten, & Manchester 2004). The time series data were folded using pulsar ephemerides derived from the IPTA DR2 (Perera et al 2019).…”

“…Precise ToA and DM estimations at low frequencies using the traditional narrowband technique are restricted by the following factors: (1) the estimated DM and frequency-dependent profile shape evolution are covariant with each other, (2) frequencycollapsing the data to improve the signal-to-noise ratio (S/N) can introduce smear if uncorrected DM variations are present, and (3) interstellar scatter broadening can introduce systematic biases in the estimated DMs. To minimise the systematic errors introduced by factors (1) and (2), we adopt an iterative strategy that is c See Susobhanan et al (2021) for discussion on the frequency labels for uGMRT data implemented in pinta. For uGMRT observations carried out between 2019 October 18 and 2021 July 29 using the TGC control system, the frequency labels require an additional +10 kHz correction.…”