Prospects for Detecting Fast Transients with the Radio Telescopes of the Argentine Institute of Radio Astronomy

Abstract

Currently, 6 out of 30 known magnetars had pulsed radio emission detected. In this work, we evaluated the possibility of detecting radio transient events from magnetars with the telescopes of the Instituto Argentino de Radioastronomía (IAR). To this aim, we made daily observations of the magnetar XTE J1810−197 from 02-Sep-22 to 30-Nov-22. We analysed the observations by applying ephemeris folding and single pulse searches.We fitted a timing model to our observations and were able to detect the magnetar on 6 of the 36 observing sessions with signal-to-noise ratios at the limit of detectability, 3.3 ≤ S/N ≤ 4.1. We searched for individual pulses in one of these 6 days and found 7 individual pulses with 8.5 ≤ S/N ≤ 18.8. The dispersion measure changed slightly between pulses within a range of 178 ≤ DM [pc cm−3] ≤ 182. The pulse with S/N = 18.8 has an associated DM of 180 pc cm−3. We confirmed that we can detect pulsed radio emission in the band of 1400 − 1456 MHz from magnetars with a time resolution of 146 μs, being able to detect both integrated pulse profiles and individual pulses.

Actualmente, s´olo 6 de los 30 magnetares conocidos han tenido emisi´on en radio reportada. En este trabajo, evaluamos la posibilidad de detectar eventos transitorios en radio provenientes de magnetares, usando los telescopios del Instituto Argentino de Radio Astronom´ıa (IAR). Para ello, realizamos observaciones diarias del magnetar XTE J1810−197 desde el 02-Sep-22 al 30-Nov-22. Analizamos las observaciones empleando integraciones en fase y b´usqueda de pulsos individuales. Ajustamos un modelo de timing actualizado para nuestras observaciones y detectamos al magnetar en 6 de 36 d´ıas observados con una se˜nal a ruido de 3.3 ≤ S/N ≤ 4.1. Buscamos pulsos individuales en uno de estos 6 d´ıas y encontramos 7 pulsos con 8.5 ≤ S/N ≤ 18.8. La medida de dispersi´on vari´o ligeramente entre los pulsos dentro del rango 178 ≤ DM [pc cm−3 ] ≤ 182. El pulso con S/N = 18.8 tiene una DM asociada de 180 pc cm−3 . Demostramos que podemos detectar emisi´on pulsada en radio (1400 − 1456 MHz) de magnetares con una resoluci´on temporal de 146 µs, observando perfiles de pulsos integrados y pulsos individuales.