Astrophysics with Compact Objects: An Indian Perspective, Present Status and Future Vision

TL;DR

This paper reviews India's current and future efforts in astrophysics involving compact objects, highlighting observational advances, upcoming missions, and the potential for multi-messenger astronomy to deepen understanding of extreme physical phenomena.

Contribution

It provides a comprehensive overview of Indian astrophysics research on compact objects, emphasizing recent achievements, ongoing projects, and future prospects within the context of global multi-messenger astronomy.

Findings

Significant breakthroughs in pulsar studies using uGMRT and OORT.

Revolutionized spectro-temporal observations with AstroSat.

Upcoming XPoSat mission to enable polarization measurements in X-ray band.

Abstract

Astrophysical compact objects, viz., white dwarfs, neutron stars, and black holes, are the remnants of stellar deaths at the end of their life cycles. They are ideal testbeds for various fundamental physical processes under extreme conditions that are unique in nature. Observational radio astronomy with uGMRT and OORT facilities has led to several important breakthroughs in studies of different kinds of pulsars and their emission mechanisms. On the other hand, accretion processes around compact objects are at the core of Indian astronomy research. In this context, AstroSat mission revolutionized spectro-temporal observations and measurements of accretion phenomena, quasi-periodic oscillations, and jet behaviour in binary systems hosting compact objects. Moreover, recently launched XPoSat mission is set to provide an impetus to these high-energy phenomena around compact objects by enabling us to conduct polarization measurements in the X-ray band. Further, during the past decade, numerous gravitational wave signals have been observed from coalescing black holes and neutron stars in binary systems. Recent simultaneous observation of the GW170817 event in both gravitational waves and electromagnetic channels has ushered in the era of multi-messenger astronomy. In the future, synergistic efforts among several world-class observational facilities, e.g., LIGO-India, SKA, TMT, etc., within the Indian astrophysics community will provide a significant boost to achieve several key science goals that have been delineated here. In general, this article plans to highlight scientific projects being pursued across Indian institutions in this field, the scientific challenges that this community would be focusing on, and the opportunities in the coming decade. Finally, we have also mentioned the required resources, both in the form of infrastructural and human resources.