Fast Radio Bursts (1904.07947v1)

Abstract: The discovery of radio pulsars over a half century ago was a seminal moment in astronomy. It demonstrated the existence of neutron stars, gave a powerful observational tool to study them, and has allowed us to probe strong gravity, dense matter, and the interstellar medium. More recently, pulsar surveys have led to the serendipitous discovery of fast radio bursts (FRBs). While FRBs appear similar to the individual pulses from pulsars, their large dispersive delays suggest that they originate from far outside the Milky Way and hence are many orders-of-magnitude more luminous. While most FRBs appear to be one-off, perhaps cataclysmic events, two sources are now known to repeat and thus clearly have a longer-lived central engine. Beyond understanding how they are created, there is also the prospect of using FRBs -- as with pulsars -- to probe the extremes of the Universe as well as the otherwise invisible intervening medium. Such studies will be aided by the high implied all-sky event rate: there is a detectable FRB roughly once every minute occurring somewhere on the sky. The fact that less than a hundred FRB sources have been discovered in the last decade is largely due to the small fields-of-view of current radio telescopes. A new generation of wide-field instruments is now coming online, however, and these will be capable of detecting multiple FRBs per day. We are thus on the brink of further breakthroughs in the short-duration radio transient phase space, which will be critical for differentiating between the many proposed theories for the origin of FRBs. In this review, we give an observational and theoretical introduction at a level that is accessible to astronomers entering the field.

• The paper provides a comprehensive review of Fast Radio Bursts, detailing their observed properties, potential origins, and significance as cosmological probes.
• FRBs are ultrafast, bright radio pulses characterized by high dispersion measures indicating extragalactic origin, with observations revealing both repeating and apparently isolated events.
• Future advancements in wide-field radio telescopes and multi-messenger approaches are crucial for increasing FRB detection rates, identifying host galaxies, and distinguishing between diverse origin models.

Overview of Fast Radio Bursts Paper

The academic paper "Fast Radio Bursts" by E. Petroff, J.W.T. Hessels, and D.R. Lorimer provides a comprehensive examination of Fast Radio Bursts (FRBs), a significant topic in contemporary astronomy. The paper explores the origins, properties, and implications of FRBs, contributing extensively to understanding this relatively new astronomical phenomenon.

Originally detected via pulsar surveys, FRBs are recognized for their ultrafast, bright radio pulse characteristics, exhibiting significant dispersive delays indicative of an extragalactic origin. The paper discusses the detection of two distinct subsets of FRBs: those that appear to be isolated, possibly cataclysmic events, and those that repeat, suggesting a persistent central engine. The distribution of these bursts across the sky and their high event rates imply a substantial, yet relatively unexplored, celestial population.

A significant focus of the paper is the potential application of FRBs in probing cosmic extremes, as with pulsars. Despite their currently low detection numbers relative to their expected frequency, advancements in wide-field radio telescope instrumentation are set to improve the detection rate, offering opportunities to differentiate among the diverse theoretical models accounting for FRB origins.

From a technical standpoint, FRBs are characterized by their high dispersion measures (DM), which often exceed the Galactic electron content along the line-of-sight, suggesting an extragalactic path length. The paper highlights the technological and methodological advances in observing techniques and instrument sensitivity which have led to the FRBs' discovery and ongoing investigation.

The theoretical implications discussed involve two significant angles: the nature of FRBs themselves and their utility as cosmological probes. FRBs potentially offer a new observational window into extreme astrophysical environments and the intergalactic medium. Such endeavors are underpinned by large-scale collaborations and cutting-edge technology, from pulsar-like surveys to real-time detection capabilities and cross-frequency observational campaigns, enhancing our view of these transient phenomena.

The authors stress the importance of multi-wavelength and multi-messenger approaches to uncover the nature of the radio waves emitted via these bursts. Moreover, the determination of FRB redshifts and host galaxy associations is crucial, particularly for repeaters, whose paper has so far suggested affiliations with faint dwarf galaxies - an aspect echoing certain types of supernovae and gamma-ray bursters, but distinctively enigmatic due to the paucity of optical counterparts.

Despite FRBs' short observational history, the paper suggests that upcoming broad-band, real-time detection capabilities will yield a higher number of FRBs, facilitating definitive identification of their origins and the conditions of their environments. The event localization and characterization, as outlined, are vital to advancing the scientific community’s understanding of the cosmological backdrop these bursts illuminate.

In conclusion, the paper predicts breakthroughs in FRB origins and characteristics through continued technological advancements in telescopic arrays and data analysis methodologies. We anticipate significant contributions to astrophysics and cosmology from the paper of FRBs, potentially unraveling mysteries of both local galactic and extragalactic phenomena. The implications for improving our understanding of the universe's structure are substantial, highlighting the relevance of this nascent field.