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## Full-Text Articles in Physics

Search For Subsolar-Mass Ultracompact Binaries In Advanced Ligo's First Observing Run, B. P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

#### Search For Subsolar-Mass Ultracompact Binaries In Advanced Ligo's First Observing Run, B. P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

*Physics Faculty Research & Creative Works*

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2 M_{⊙}-1.0 M_{⊙} using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning (0.2 M_{⊙}, 0.2 M_{⊙}) ultracompact binaries to be less than 1.0 x 10^{6} Gpc^{-3} yr^{-1} and the coalescence rate of a similar distribution of (1.0 M_{⊙}, 1.0 M_{⊙}) ultracompact binaries to be less than 1.9 ...

Gw170817: Measurements Of Neutron Star Radii And Equation Of State, B. P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

#### Gw170817: Measurements Of Neutron Star Radii And Equation Of State, B. P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

*Physics Faculty Research & Creative Works*

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were ...

Search For Tensor, Vector, And Scalar Polarizations In The Stochastic Gravitational-Wave Background, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

#### Search For Tensor, Vector, And Scalar Polarizations In The Stochastic Gravitational-Wave Background, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

*Physics Faculty Research & Creative Works*

The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically polarized gravitational waves. We find ...

Gw170817: Implications For The Stochastic Gravitational-Wave Background From Compact Binary Coalescences, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

#### Gw170817: Implications For The Stochastic Gravitational-Wave Background From Compact Binary Coalescences, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

*Physics Faculty Research & Creative Works*

The LIGO Scientific and Virgo Collaborations have announced the event GW170817, the first detection of gravitational waves from the coalescence of two neutron stars. The merger rate of binary neutron stars estimated from this event suggests that distant, unresolvable binary neutron stars create a significant astrophysical stochastic gravitational-wave background. The binary neutron star component will add to the contribution from binary black holes, increasing the amplitude of the total astrophysical background relative to previous expectations. In the Advanced LIGO-Virgo frequency band most sensitive to stochastic backgrounds (near 25 Hz), we predict a total astrophysical background with amplitude Ω_{GW}(*f ...*

First Search For Nontensorial Gravitational Waves From Known Pulsars, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

#### First Search For Nontensorial Gravitational Waves From Known Pulsars, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

*Physics Faculty Research & Creative Works*

We present results from the first directed search for nontensorial gravitational waves. While general relativity allows for tensorial (plus and cross) modes only, a generic metric theory may, in principle, predict waves with up to six different polarizations. This analysis is sensitive to continuous signals of scalar, vector, or tensor polarizations, and does not rely on any specific theory of gravity. After searching data from the first observation run of the advanced LIGO detectors for signals at twice the rotational frequency of 200 known pulsars, we find no evidence of gravitational waves of any polarization. We report the first upper ...