Apertif is a phased-array feed system for the Westerbork Synthesis
Radio Telescope (WSRT), providing forty instantaneous beams over 300
MHz of bandwidth. This first data release includes observations in the
first year of survey operations, from 1 July 2019 through 30 June
2020. The data release includes all raw observational data for a total
of 221 observations of 160 independent target fields, covering
approximately one thousand square degrees of sky. A subset of
processed data products, meeting specified quality assessment criteria
as outlined in Adams et al. (2022), are also released. Images and
cubes are released on a per beam basis, and 3374 beams (of 7640
considered) are included in this data release. The processed data
products are only available for the upper 150 MHz of the band over the
range 1280–1430 MHz. The first 12.5 MHz of data are flagged due to
persistent RFI resulting in a nominal bandwidth of 137.5 MHz and
central frequency of 1361.25 MHz. The data products are not
primary-beam corrected, however the primary-beam images are provided
separately that may be used for mosaicking or for correction of
individual images. This service queries the polarization cubes from
the first data release of Apertif. In order to prevent bandwidth
depolarization and enable rotation measure synthesis studies, Stokes Q
and U cubes with a frequency resolution of 6.25 MHz are produced. The
cubes have a smaller spatial extent of 2.7 deg × 2.7 deg (2049 × 2049
pixels, with 4''/pixel ) than the continuum or Stokes V images but
still extend well beyond the primary beam.
This service queries the continuum catalogue based on the first data
release of Apertif continuum images at a central frequency 1355 MHz,
with a bandwidth of ~150 MHz and angular resolution of up to 10''. The
catalogue contains 249672 radio sources, many of which have been
detected for the first time at these frequencies. Source extraction
methods are described in Kutkin et al. 2022. A companion VO table
contains the continuum images corresponding to this catalogue (see
https://vo.astron.nl/apertif_dr1/q/apertif_dr1_continuum_images/form).
Apertif Time Domain FRB detection cone search (DR2)
Short Name:
Detected FRB
Date:
31 Jul 2024 11:50:27
Publisher:
ASTRON
Description:
This is the final, full data release from the Apertif Radio Transient
System (ARTS), a supercomputing radio-telescope instrument that
performed real-time FRB detection and localisation on the Westerbork
Synthesis Radio Telescope (WSRT) interferometer. It reached
coherent-addition sensitivity over the entire field of the view of the
primary- dish beam. The Apertif FRB survey (ALERT) detected 24 new
FRBs, and interferometrically localised each of these to 0.4−10 sq.
arcmin. All detections are broad band and very narrow, of order 1 ms
duration, with high dispersion measures. Please note that the ARTS DR2
collection includes all data from the DR1 collection.
Apertif Time Domain FRB detection cone search (DR1)
Short Name:
Detected FRB
Date:
31 Jul 2024 11:50:09
Publisher:
ASTRON
Description:
This is the first release of data from the Apertif Radio Transient
System (ARTS), a supercomputing radio-telescope instrument that
performs real-time FRB detection and localisation on the Westerbork
Synthesis Radio Telescope (WSRT) interferometer. It reaches
coherent-addition sensitivity over the entire field of the view of the
primary- dish beam. After commissioning results verified the system
performed as planned, we initiated the Apertif FRB survey (ALERT).
Over the first 5 weeks we observed at design sensitivity in 2019, we
detected 5 new FRBs, and interferometrically localised each of these
to 0.4−10 sq. arcmin. All detections are broad band and very narrow,
of order 1 ms duration, and unscattered. Dispersion measures are
generally high. Please note that the ARTS DR1 collection available
from this end-point is superseded by the ARTS DR2 collection. DR2
includes all data from the DR1 collection that can be queried here.
The ARTS DR2 FRB detection cone search can be reached at
https://vo.astron.nl/arts_dr2/q/det_cone/form.
Apertif Time Domain FRB observation cone search (DR2)
Short Name:
Observed FRBs
Date:
31 Jul 2024 11:50:27
Publisher:
ASTRON
Description:
This is the final, full data release from the Apertif Radio Transient
System (ARTS), a supercomputing radio-telescope instrument that
performed real-time FRB detection and localisation on the Westerbork
Synthesis Radio Telescope (WSRT) interferometer. It reached
coherent-addition sensitivity over the entire field of the view of the
primary- dish beam. The Apertif FRB survey (ALERT) detected 24 new
FRBs, and interferometrically localised each of these to 0.4−10 sq.
arcmin. All detections are broad band and very narrow, of order 1 ms
duration, with high dispersion measures. Please note that the ARTS DR2
collection includes all data from the DR1 collection.
Apertif Time Domain FRB observation cone search (DR1)
Short Name:
Observed FRBs
Date:
31 Jul 2024 11:50:09
Publisher:
ASTRON
Description:
This is the first release of data from the Apertif Radio Transient
System (ARTS), a supercomputing radio-telescope instrument that
performs real-time FRB detection and localisation on the Westerbork
Synthesis Radio Telescope (WSRT) interferometer. It reaches
coherent-addition sensitivity over the entire field of the view of the
primary- dish beam. After commissioning results verified the system
performed as planned, we initiated the Apertif FRB survey (ALERT).
Over the first 5 weeks we observed at design sensitivity in 2019, we
detected 5 new FRBs, and interferometrically localised each of these
to 0.4−10 sq. arcmin. All detections are broad band and very narrow,
of order 1 ms duration, and unscattered. Dispersion measures are
generally high. Please note that the ARTS DR1 collection available
from this end-point is superseded by the ARTS DR2 collection. DR2
includes all data from the DR1 collection that can be queried here.
The ARTS DR2 FRB observation cone search can be reached at
https://vo.astron.nl/arts_dr2/q/obs_cone/form.
