The ngVLA Science Working Groups

The ngVLA Science Working Groups (SWGs), as given below, have been restructured to better align with the science priorities articulated by the Astro2020 Decadal Survey report. Anyone interested in joining an SWG is welcome to sign up by using the "Contact Us" link at the bottom of this page.

The science goals proposed by the original four are described in a series of white papers published in the ngVLA Memo Series.


SWG1: Stars, Planetary Systems, and their Origins

Co-Chairs: Brenda Matthews (NRC-Victoria) & David Wilner (Harvard CfA)

Past Chairs: Andrea Isella (Rice University), Arielle Moullet (SOFIA), Chat Hull (NRAO)

Topics:  (proto-)planetary systems and formation; cloud cores to stars; Solar System; SETI

The high resolution and sensitivity of the ngVLA in the 1.2 – 116 GHz frequency regime will pave the way for revolutionary new studies of stars, planets, and how they form. Major science drivers include: 1) protoplanetary disks, where the longer wavelengths and the unprecedented angular resolution will enable imaging of dust substructures in the terrestrial planet forming zones around young stars in nearby star-forming regions; 2) embedded protostars, where the longer wavelengths will penetrate dense envelopes and probe disks in formation and reveal binaries and multiplicity out to much larger distances in the Galaxy; 3) high-mass star formation, where the high sensitivity will allow us to resolve the density structure and dynamics of the youngest HII regions and high-mass protostellar jets; 4) planetary science, where the unprecedented sensitivity will allow deep mapping of planetary atmospheres on short timescales and the resolution and sensitivity will enable detection of exoplanets through astrometry; and 5) SETI (Search for Extraterrestrial Intelligence), where the vast frequency and sky coverage of the ngVLA coupled with improved targeting derived from missions such as Gaia and TESS will bring the search for technosignatures from beyond the Solar System into a new era.

 


SWG2: Astrochemistry and the Molecular Emergence of Life

Co-Chairs: Brett McGuire (MIT) & Jennifer Bergner (Chicago)

Past Chairs: of previous SWG1: Brenda Matthews (NRC-Victoria), Andrea Isella (Rice University), Arielle Moullet (SOFIA), Chat Hull (NRAO)

Topics: molecular astrochemistry; prebiotic molecules; star and planet-forming regions

The combination of broad instantaneous bandwidth, high sensitivity, and high spectral resolution across a large range in angular resolution will make the ngVLA an unparalleled tool for molecular astrochemistry.  Indeed, these capabilities are required to make meaningful progress in understanding the astrochemical production and inheritance of prebiotic molecules.  With its high angular resolution, the ngVLA will probe molecular compositions on smaller scales than ever before, unveiling the chemistry of the innermost regions of protostellar cores and the terrestrial planet zones of protoplanetary disks.  The spectral breadth of the ngVLA will enable the simultaneous detection and imaging of multitudes of spectral lines from both simple and complex organic molecules, providing comprehensive constraints on the organic compositions and emitting conditions in star- and planet-forming regions.  Key science drivers for astrochemistry include 1) the detection of new, complex, low-abundance species; 2) the characterization of rare isotopically-substituted species; and 3) the exploration of physical and chemical co-evolution on very small spatial scales.


SWG3: Galaxies and Galaxy Evolution

Co-Chairs: Fabian Walter (MPIA) & (TBD)

Past Chairs: Dominik Riechers (Cologne), Caitlin Casey (Texas), Mark Lacy (NRAO), Jackie Hodge (Leiden); of previous SWG2: Daniel Dale (Wyoming), Cornelia Lang, Eric Murphy (Caltech), Adam Leroy (Ohio State)

Topics: galaxies at all redshifts; cool gas and dust; dynamics; Active Galactic Nuclei (AGN)/SMBHs

The ngVLA will be a unique tool for studying the detailed astrophysics of star formation in galaxies, all the way from the Local Group to distant galaxies at cosmic dawn. With its unprecedented combination of high angular resolution and both line and continuum sensitivity, the ngVLA will provide new insight on the fundamental physics behind radio emission; allow detailed spectroscopic characterization of the interstellar medium in galaxies; directly measure the ionizing photon rate of newly formed massive stars; and study the role of magnetic fields in the star formation process. The combination of sensitivity and astrometric accuracy promised by the ngVLA will further allow studies of the motions around black holes and at the base of their jets, measurements of proper motions in Local Group galaxies, and refinements to our knowledge of galactic structure. Pushing to higher redshifts, the ngVLA will enable unprecedented advances in studies of galaxy formation over cosmic time. Its sensitivity and frequency coverage will allow the detection of cool gas and dust in relatively "normal" distant galaxies, including molecular gas tracers such as low-J CO, H20, HCN, and HCO+; synchrotron and free-free continuum emission; and even the exciting possibility of thermal emission at the highest (z ~ 7) redshifts. The ultra-wide bandwidths will allow a complete sampling of radio/submillimeter SEDs, as well as the simultaneous detection of multiple emission lines. Finally, the superb angular resolution will enable spatially resolved mapping and allow detailed studies of the morphologies and dynamics of these systems, such as dynamical modeling of disks/mergers, determining the properties of outflows, measuring black hole masses from gas disks, and resolving multiple AGN nuclei. 


SWG4: Pulsars, Cosmology, and Fundamental Physics

Co-Chairs: Megan DeCesar (George Mason) & (TBD)

Past Chairs: Joe Lazio (Caltech/JPL), Geoff Bower (ASIAA), Paul Demorest (NRAO)

Topics: tests of gravity; relativity and stellar evolution; dark matter; cosmological phase transitions

The high sensitivity of the ngVLA will allow unprecedented studies of pulsars–especially distant pulsars that are heavily scattered at ~1-2 GHz and too faint to be detected with current telescopes above ~3 GHz–with ramifications for cosmology and fundamental physics. Among  the primary targets are pulsars in the Galactic Center, which represent clocks moving in the space-time potential of a supermassive black hole. Identifying, imaging, and timing such pulsars with the ngVLA will enable qualitatively new tests of theories of gravity. More generally, this will offer the opportunity to constrain the history of star formation, stellar dynamics, stellar evolution, and the magneto-ionic medium in the Galactic Center. The ngVLA’s combination of sensitivity and frequency range will allow it to probe much deeper into the likely Galactic Center pulsar population to discover rare systems, like pulsar-black hole binaries, and to address fundamental questions in relativity and stellar evolution. Galactic Center pulsars may also provide a means to probe the distribution and clumpiness of dark matter in the Galaxy, and the presence or absence of Galactic Center millisecond pulsars in particular will strongly constrain the origin of the diffuse GeV excess to either magnetospheric gamma-ray emission from millisecond pulsars or to dark matter annihilation. In addition, detection and characterization of a stochastic gravitational wave background with pulsar timing arrays has the potential to probe inflation-era cosmological phase transitions. The ngVLA will allow an expansion of existing pulsar timing arrays through its unmatched sensitivity, allowing higher-precision timing of current array pulsars as well as the addition of many more pulsars to these arrays.


SWG5: Exploring the Dynamic Universe

Co-Chairs: Rachel Osten (STScI) & (TBD)

Past Chairs: of previous SWG4: Joe Lazio (Caltech/JPL), Geoff Bower (ASIAA), Paul Demorest (NRAO)

Topics: transient and variable sources; astrophysics enabled by multi-messenger detections; astrophysical plasmas; black holes

The ngVLA will provide powerful probes of the transient and high energy universe, revealing new physics in the new era of multi-messenger astronomy. Electromagnetic counterparts to gravitational wave events provide a window into the extreme physics of neutron star mergers. Tidal disruption of stars around massive black holes provides a unique laboratory for studying accretion-jet physics and exploring the growth of black holes in galactic centers. The physics of plasmas, from the Sun to flaring stars to galaxy clusters, will also be uniquely probed by this instrument. The ngVLA will be the ultimate black hole hunting machine, surveying everything from the remnants of massive stars to the supermassive black holes that lurk in the centers of galaxies. High-resolution imaging abilities will separate low-luminosity black holes in our local Universe from background sources, thereby providing critical constraints on their formation and growth for all sizes and mergers of black hole–black hole binaries, with complementarity to next-generation gravitational wave facilities. The ngVLA will also identify the radio counterparts to transient sources discovered by gravitational wave, neutrino, optical and high-energy observatories. Its high-resolution, fast-mapping capabilities will make it the preferred instrument for pinpointing transients associated with violent phenomena such as supermassive black hole mergers and blast waves.