Glossary
- BBH
- Binary black hole system, a binary system composed of two black holes.
- BNS
- Binary neutron star, a binary system composed of two neutron stars.
- BNS range
- A figure of merit to describe the sensitivity of a gravitational-wave
detector to BNS mergers, defined as the average luminosity
distance at which the merger of two \(1.4~M_\odot\) objects would
be detectable with a signal to noise ratio of 8. See also Burst
range.
- Burst range
- A figure of merit to describe the sensitivity of a gravitational-wave
detector to unmodeled bursts, defined with reference to optimistic
models of gravitational wave emissions from stellar collapse as the
average luminosity distance at which a monochromatic burst at 150 Hz
with a fluence of \(E_\mathrm{GW} = 10^{-2} M_\odot c^2\) would be
detectable with a signal to noise ratio of 8. See also BNS
range.
- CBC
- Compact binary coalescence.
- FITS
- Flexible Image Transport System, a format for astronomical tables,
images, and multidimensional data sets.
- GCN
- The Gamma-ray Coordinates Network (https://gcn.gsfc.nasa.gov), a portal
for discoveries and observations of astronomical transients.
Historically, GCN has served high-energy satellites but now also other
electromagnetic wavelengths and also gravitational-wave, cosmic ray,
and neutrino facilities.
- GCN Circular
- A human-readable astronomical bulletin distributed through GCN.
- GCN Notice
- A machine-readable alert distributed through GCN.
- GraceDB
- Gravitational Wave Candidate Event Database (https://gracedb.ligo.org),
the official public marshal portal for LIGO/Virgo candidates.
- GRB
- Gamma-ray burst.
- HEALPix
- Hierarchical Equal Area isoLatitude Pixelation, a scheme for indexing
positions on the unit sphere. See https://healpix.sourceforge.io.
- HEN
- High Energy Neutrino, particularly in the context of multi-messenger
GW+HEN follow-up.
- KAGRA
- Kamioka Gravitational Wave Detector, an underground gravitational-wave
detector in the Kamioka mine in Japan.
- LHO
- LIGO Hanford Observatory (see LHO observatory home page), site of a 4 km gravitational-wave
detector in Hanford, Washington, USA.
- LLO
- LIGO Livingston Observatory (see LLO observatory home page), site of a 4 km gravitational-wave
detector in Livingston, Louisiana, USA.
- MassGap
- Compact binary systems with at least one compact object whose mass is
in the hypothetical “mass gap” between neutron stars and black holes,
defined here as 3-5 solar masses.
- MOC
- Multi-Order Coverage map, a format to describe the coverage of an
arbitrary region on the unit sphere. A MOC consists of a list of
HEALPix cells at different depths. For the specification, see
the HiPS IVOA Recommendation.
- NSBH
- Neutron star black hole, a binary system composed of one neutron star
and one black hole.
- primary
- When referring to the two component compact objects or the masses of
the two component compact objects in a binary, the primary is the
more massive one, i.e., \(m_1 \geq m_2\). See secondary.
- secondary
- When referring to the two component compact objects or the masses of
the two component compact objects in a binary, the secondary is the
less massive one, i.e., \(m_2 \leq m_1\). See primary.
- SN
- Supernova.
- SNR
- Signal-to-noise ratio, here applied to gravitational-wave signals. It
is defined the square root of the integral over frequency of the power
spectral density of the gravitational-wave signal over the integral
over frequency of the average power spectral density of the noise.
- Terrestrial
- Classification for signals in gravitational-wave detectors that are of
instrumental or environmental origin. Terrestrial signals are not
astrophysical and not due to gravitational waves. Some examples of
sources of terrestrial signals are statistical noise fluctuations,
detector glitches, and ground motion.
- Virgo
- Virgo Observatory (see Virgo observatory home page), site of a 3 km gravitational-wave detector
in Cascina, Italy.
- VOEvent
- An XML format for describing astronomical transients. For the
specification, see the official VOEvent IVOA Recommendation.
- VTP
- VOEvent Transport Protocol, a simple TCP-based protocol for sending and
receiving VOEvents, used by GCN. For the specification, see the
official VTP IVOA recommendation.