Target of Opportunity Observations of Gravitational Wave Events with Vera C. Rubin Observatory

Abstract

The discovery of the electromagnetic counterpart to the binary neutron star merger GW170817 has opened the era of gravitational-wave multi-messenger astronomy. Rapid identification of the optical/infrared kilonova enabled a precise localization of the source, which paved the way to deep multiwavelength follow-up and its myriad of related science results. Fully exploiting this new territory of exploration requires the acquisition of electromagnetic data from samples of neutron star mergers and other gravitational wave sources. After GW170817, the frontier is now to map the diversity of kilonova properties and provide more stringent constraints on the Hubble constant, and enable new tests of fundamental physics. The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) can play a key role in this field in the 2020s, when an improved network of gravitational-wave detectors is expected to reach a sensitivity that will enable the discovery of a high rate of merger events involving neutron stars (∼tens per year) out to distances of several hundred Mpc. We design comprehensive target-of-opportunity observing strategies for follow-up of gravitational-wave triggers that will make the Rubin Observatory the premier instrument for discovery and early characterization of neutron star and other compact object mergers, and yet unknown classes of gravitational wave events. * Gehrels Fellow † NASA Einstein Fellow vides numerous benefits to GW analysis, including: improved localization leading to host-galaxy identification (e.g., Coulter et al. 2017); determination of the source's distance and energy scales; characterization of the progenitor's local environment (e.g.,

Discovering gravitationally lensed gravitational waves: predicted rates, candidate selection, and localization with the Vera Rubin Observatory

“…Observations will therefore need to be triggered in response to such a detection. In the context of the Vera Rubin Observatory, this would take the form of a target of opportunity (ToO) observations along similar lines to those discussed by Andreoni et al (2021), albeit in response to detections in the mass gap and tuned to a lensed NS-NS interpretation. With a required sensitivity of 26th magnitude, such observations will be more time consuming than envisaged for GW detections that are not lensed, with the lightcurves in Figure 10 indicating that up to 20 minutes per epoch per filter may be required, depending on the expected magnification of the source.…”

Neutron Stars with Baryon Number Violation, Probing Dark Sectors

“…• BNV processes with final states involving photons, mesons, and charged leptons (e.g., n → e ∓ π ± ) can be expected to dump all of their energy back into the NS, raising the temperature of the NS to a potentially detectable level, given upcoming observational possibilities [474]. Put more pithily, old neutron stars should be if they are not, then this would really be quite a coup.…”

Prospects for multi-messenger detection of binary neutron star mergers in the fourth LIGO-Virgo-KAGRA observing run

“…the brightness can depend on the line of sight; Kasen et al 2017). Recently, Andreoni et al (2021) highlighted that realistic predictions on joint GW-kilonova detection should conservatively built around the capability to detect the red kilonova component. In their work, the authors show that a firm detection of red kilonovae during O4 can be obtained only within ∼ 100 Mpc, while for joint GW-kilonova detection beyond such horizon we will have to wait for O5, when the Vera Rubin Observatory will be operational.…”