THE DEEP SYNOPTIC ARRAY

The Deep Synoptic Array (DSA, formerly DSA-2000) will be a world-leading radio survey telescope and multi-messenger discovery engine. The array will consist of of 1650 × 6.15m dishes instantaneously covering the 0.7 – 2 GHz frequency range, spanning an area of 19 km × 15 km in a radio-quiet valley in Nevada. It will have near complete sampling of the uv-plane allowing us to replace a traditional correlator digital backend with a “radio camera” that produces images in real-time.  In a five-year initial survey, the DSA will image the entire viewable sky (~31,000 deg²) repeatedly over sixteen epochs, with a spatial resolution of 3.0 arcseconds, detecting >1 billion radio sources in a combined full-Stokes sky map with 500 nJy/beam rms noise. As a radio survey instrument it will be unprecedented relative to any instrument existing or planned.

Image: C. Carter

A Multi-Messenger Radio Survey Camera 

The DSA will deliver a radio counterpart to the transformative astronomical surveys of the 2020s (e.g., Rubin Observatory, SPHEREx, SRG/eROSITA).

Radio Camera Products

  • 10 wideband continuum channels (I, 0.7 – 2.0 GHz)

  • 605 continuum channels (IQUV, 0.7 – 2.0 GHz @ 2.15 MHz resolution)

  • 5600 low-resolution channels (0.7 – 1.45 GHz @ 134 kHz resolution, HI: 56 km/s @ z = 1, 28 km/s @ z = 0)

  • Tuneable zoom band A: 4096 channels (I), 8 kHz (1.8 km/s) [extragalactic HI, D < 100 Mpc]

  • Tuneable zoom band B: 2048 channels (I), 1.05 kHz (0.22 km/s) [Galactic HI, Δv = 400 km/s]

  • Output: 1 image / cubes (16k images) / 16k × 16k pixels per primary beam

Pulsar Timing Beams

  • 1.3 GHz bandwidth (0.7 – 2.0 GHz)

  • 4 steerable, full polarization beams

  • Output: folded profiles with 2048 phase bins, 1 second integration time, and 605 coherently dedispersed channels

  • 200 pulsars monitored monthly

Chronoscope Products

  • 4000 targeted beams for pulsar searching and timing (0.1ms, 134kHz res)

  • 200,000 uniformly spaced beams for pulsar searching (0.1ms, 134kHz res)

  • 6,000,000 uniformly spaced beams FRB searching (1ms, 134kHz res)

  • Output: low-latency FRB alerts, pulsar folded profiles. 

Parameter Value
Antennas 1650 × 6.15-m dishes
Frequency coverage 0.7 – 2.0 GHz
Primary beam FWHM 3.1° at 1.35 GHz
Synthesized beam FWHM 3.0″ at 1.35 GHz
Continuum sensitivity 600 nJy in 1 hr
All-sky survey 31,000 deg2 @ 500 nJy/beam
Number of unique radio sources > 1 billion
HI: z < 1 (5600 × 130 kHz) 5 million galaxies
HI: < 100 Mpc (4192 × 8 kHz) 100,000 galaxies
HI: Galactic (960 × 1 kHz) 10″ resolution at 0.25 km/s
RM grid (625 × 2.1 MHz) 10 million sources
Fast radio bursts 50,000 localized to < 0.5″
Pulsar search 22,000 new pulsars
Millisecond pulsar timing TOA data for 200 pulsars

Unparalleled Survey Speed

Survey speed and sensitivity of the DSA and other current and planned radio telescopes that operate at 1.4 GHz.

 

The DSA is unique among current and planned large radio telescopes, in that it will operate as a dedicated survey telescope. This allows the array design to be highly optimized to maximize survey speed—a low cost antenna with an ambient temperature receiver will operate at a single frequency band, with all observations conducted in blocks of 15 minutes. The homogeneous nature of the resulting data is a key factor that enables the radio camera approach for the DSA, with data products that will  bypass the growing data deluge problem in radio astronomy, enabling broader community access to the radio sky.  This strategy will allow the DSA to survey the sky at a rate ~1000x the current state of the art in the US (the VLA), ~200x the state of the art worldwide (MeerKAT), and ~6x faster than any array in development.