10 research outputs found
The Third Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
We present 294 pulsars found in GeV data from the Large Area Telescope (LAT)
on the Fermi Gamma-ray Space Telescope. Another 33 millisecond pulsars (MSPs)
discovered in deep radio searches of LAT sources will likely reveal pulsations
once phase-connected rotation ephemerides are achieved. A further dozen optical
and/or X-ray binary systems co-located with LAT sources also likely harbor
gamma-ray MSPs. This catalog thus reports roughly 340 gamma-ray pulsars and
candidates, 10% of all known pulsars, compared to known before Fermi.
Half of the gamma-ray pulsars are young. Of these, the half that are undetected
in radio have a broader Galactic latitude distribution than the young
radio-loud pulsars. The others are MSPs, with 6 undetected in radio. Overall,
>235 are bright enough above 50 MeV to fit the pulse profile, the energy
spectrum, or both. For the common two-peaked profiles, the gamma-ray peak
closest to the magnetic pole crossing generally has a softer spectrum. The
spectral energy distributions tend to narrow as the spindown power
decreases to its observed minimum near erg s, approaching the
shape for synchrotron radiation from monoenergetic electrons. We calculate
gamma-ray luminosities when distances are available. Our all-sky gamma-ray
sensitivity map is useful for population syntheses. The electronic catalog
version provides gamma-ray pulsar ephemerides, properties and fit results to
guide and be compared with modeling results.Comment: 142 pages. Accepted by the Astrophysical Journal Supplemen
Incremental Fermi Large Area Telescope Fourth Source Catalog
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog of gamma-ray sources. Based on the first twelve years of science data in the energy range from 50 MeV to 1 TeV, it contains 6658 sources. The analysis improves on that used for the 4FGL catalog over eight years of data: more sources are fit with curved spectra, we introduce a more robust spectral parameterization for pulsars, and we extend the spectral points to 1 TeV. The spectral parameters, spectral energy distributions, and associations are updated for all sources. Light curves are rebuilt for all sources with 1 yr intervals (not 2 month intervals). Among the 5064 original 4FGL sources, 16 were deleted, 112 are formally below the detection threshold over 12 yr (but are kept in the list), while 74 are newly associated, 10 have an improved association, and seven associations were withdrawn. Pulsars are split explicitly between young and millisecond pulsars. Pulsars and binaries newly detected in LAT sources, as well as more than 100 newly classified blazars, are reported. We add three extended sources and 1607 new point sources, mostly just above the detection threshold, among which eight are considered identified, and 699 have a plausible counterpart at other wavelengths. We discuss degree-scale residuals to the global sky model and clusters of soft unassociated point sources close to the Galactic plane, which are possibly related to limitations of the interstellar emission model and missing extended sources
Incremental Fermi Large Area Telescope Fourth Source Catalog
We present an incremental version (4FGL-DR3, for Data Release 3) of the
fourth Fermi-LAT catalog of gamma-ray sources. Based on the first twelve years
of science data in the energy range from 50 MeV to 1 TeV, it contains 6658
sources. The analysis improves on that used for the 4FGL catalog over eight
years of data: more sources are fit with curved spectra, we introduce a more
robust spectral parameterization for pulsars, and we extend the spectral points
to 1 TeV. The spectral parameters, spectral energy distributions, and
associations are updated for all sources. Light curves are rebuilt for all
sources with 1 yr intervals (not 2 month intervals). Among the 5064 original
4FGL sources, 16 were deleted, 112 are formally below the detection threshold
over 12 yr (but are kept in the list), while 74 are newly associated, 10 have
an improved association, and seven associations were withdrawn. Pulsars are
split explicitly between young and millisecond pulsars. Pulsars and binaries
newly detected in LAT sources, as well as more than 100 newly classified
blazars, are reported. We add three extended sources and 1607 new point
sources, mostly just above the detection threshold, among which eight are
considered identified, and 699 have a plausible counterpart at other
wavelengths. We discuss degree-scale residuals to the global sky model and
clusters of soft unassociated point sources close to the Galactic plane, which
are possibly related to limitations of the interstellar emission model and
missing extended sources.Comment: accepted in ApJS; follow-up paper to 1902.1004
Incremental Fermi Large Area Telescope Fourth Source Catalog
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi Large Area Telescope (LAT) catalog of γ-ray sources. Based on the first 12 years of science data in the energy range from 50 MeV to 1 TeV, it contains 6658 sources. The analysis improves on that used for the 4FGL catalog over eight years of data: more sources are fit with curved spectra, we introduce a more robust spectral parameterization for pulsars, and we extend the spectral points to 1 TeV. The spectral parameters, spectral energy distributions, and associations are updated for all sources. Light curves are rebuilt for all sources with 1 yr intervals (not 2 month intervals). Among the 5064 original 4FGL sources, 16 were deleted, 112 are formally below the detection threshold over 12 yr (but are kept in the list), while 74 are newly associated, 10 have an improved association, and seven associations were withdrawn. Pulsars are split explicitly between young and millisecond pulsars. Pulsars and binaries newly detected in LAT sources, as well as more than 100 newly classified blazars, are reported. We add three extended sources and 1607 new point sources, mostly just above the detection threshold, among which eight are considered identified, and 699 have a plausible counterpart at other wavelengths. We discuss the degree-scale residuals to the global sky model and clusters of soft unassociated point sources close to the Galactic plane, which are possibly related to limitations of the interstellar emission model and missing extended sources
Incremental Fermi Large Area Telescope Fourth Source Catalog
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog of gamma-ray sources. Based on the first twelve years of science data in the energy range from 50 MeV to 1 TeV, it contains 6658 sources. The analysis improves on that used for the 4FGL catalog over eight years of data: more sources are fit with curved spectra, we introduce a more robust spectral parameterization for pulsars, and we extend the spectral points to 1 TeV. The spectral parameters, spectral energy distributions, and associations are updated for all sources. Light curves are rebuilt for all sources with 1 yr intervals (not 2 month intervals). Among the 5064 original 4FGL sources, 16 were deleted, 112 are formally below the detection threshold over 12 yr (but are kept in the list), while 74 are newly associated, 10 have an improved association, and seven associations were withdrawn. Pulsars are split explicitly between young and millisecond pulsars. Pulsars and binaries newly detected in LAT sources, as well as more than 100 newly classified blazars, are reported. We add three extended sources and 1607 new point sources, mostly just above the detection threshold, among which eight are considered identified, and 699 have a plausible counterpart at other wavelengths. We discuss degree-scale residuals to the global sky model and clusters of soft unassociated point sources close to the Galactic plane, which are possibly related to limitations of the interstellar emission model and missing extended sources
Incremental Fermi Large Area Telescope Fourth Source Catalog
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi Large Area Telescope (LAT) catalog of γ-ray sources. Based on the first 12 years of science data in the energy range from 50 MeV to 1 TeV, it contains 6658 sources. The analysis improves on that used for the 4FGL catalog over eight years of data: more sources are fit with curved spectra, we introduce a more robust spectral parameterization for pulsars, and we extend the spectral points to 1 TeV. The spectral parameters, spectral energy distributions, and associations are updated for all sources. Light curves are rebuilt for all sources with 1 yr intervals (not 2 month intervals). Among the 5064 original 4FGL sources, 16 were deleted, 112 are formally below the detection threshold over 12 yr (but are kept in the list), while 74 are newly associated, 10 have an improved association, and seven associations were withdrawn. Pulsars are split explicitly between young and millisecond pulsars. Pulsars and binaries newly detected in LAT sources, as well as more than 100 newly classified blazars, are reported. We add three extended sources and 1607 new point sources, mostly just above the detection threshold, among which eight are considered identified, and 699 have a plausible counterpart at other wavelengths. We discuss the degree-scale residuals to the global sky model and clusters of soft unassociated point sources close to the Galactic plane, which are possibly related to limitations of the interstellar emission model and missing extended sources
Incremental Fermi Large Area Telescope Fourth Source Catalog
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog of gamma-ray sources. Based on the first twelve years of science data in the energy range from 50 MeV to 1 TeV, it contains 6658 sources. The analysis improves on that used for the 4FGL catalog over eight years of data: more sources are fit with curved spectra, we introduce a more robust spectral parameterization for pulsars, and we extend the spectral points to 1 TeV. The spectral parameters, spectral energy distributions, and associations are updated for all sources. Light curves are rebuilt for all sources with 1 yr intervals (not 2 month intervals). Among the 5064 original 4FGL sources, 16 were deleted, 112 are formally below the detection threshold over 12 yr (but are kept in the list), while 74 are newly associated, 10 have an improved association, and seven associations were withdrawn. Pulsars are split explicitly between young and millisecond pulsars. Pulsars and binaries newly detected in LAT sources, as well as more than 100 newly classified blazars, are reported. We add three extended sources and 1607 new point sources, mostly just above the detection threshold, among which eight are considered identified, and 699 have a plausible counterpart at other wavelengths. We discuss degree-scale residuals to the global sky model and clusters of soft unassociated point sources close to the Galactic plane, which are possibly related to limitations of the interstellar emission model and missing extended sources
Incremental Fermi Large Area Telescope Fourth Source Catalog
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog of gamma-ray sources. Based on the first twelve years of science data in the energy range from 50 MeV to 1 TeV, it contains 6658 sources. The analysis improves on that used for the 4FGL catalog over eight years of data: more sources are fit with curved spectra, we introduce a more robust spectral parametrization for pulsars, and we extend the spectral points to 1 TeV. The spectral parameters, spectral energy distributions and associations are updated for all sources. Light curves are rebuilt for all sources with 1-year intervals (not 2-month intervals). Among the 5064 original 4FGL sources, 16 were deleted, 112 are formally below the detection threshold over 12 years (but are kept in the list), while 74 are newly associated, 10 have an improved association and seven associations were withdrawn. Pulsars are split explicitly between young and millisecond pulsars. Pulsars and binaries newly detected in LAT sources, as well as more than 100 newly classified blazars, are reported. We add three extended sources and 1607 new point sources, mostly just above the detection threshold, among which eight are considered identified and 699 have a plausible counterpart at other wavelengths. We discuss degree-scale residuals to the global sky model and clusters of soft unassociated point sources close to the Galactic plane, which are possibly related to limitations of the interstellar emission model and missing extended sources