|The Supernova group at NYU
Our group studies explosive transients such as Supernovae and Gamma-Ray Bursts, which are among the most powerful explosions in the universe, and more generally, transients of various types, including exotic ones. We do this observationally with explosion data, host galaxy, and environmental data and theoretically with radiative transfer codes such as the open-source code TARDIS. We use modern machine learning and statistical methods to extract as much information as possible from our data and from our models.
Our group studies cosmic rays, magnetic fields, dark matter, and other experimental and theoretical astroparticle topics.
|Computational Astrophysics Lab
Our group uses our parallel supercomputer to investigate astrophysical phenomena by way of numerical simulations. We are currently interested in relativistic fluid and plasma dynamics relevant for the collapse and explosion of massive stars and the formation and growth of black holes.
The Pierre Auger Observatory is the world’s largest Cosmic Ray detector, located in Malargue, Argentina. It is used to study the extremely rare ultrahigh energy cosmic rays, whose energies are 106 – 108 times larger than the highest energies achieved in human accelerators.
The SDSS performs spectroscopic observations from the Apache Point Observatory and Las Campanas Observatory, studying the Milky Way, nearby galaxies, and the distant universe. Members of the CCPP have helped to plan, perform, and analyze these observations since 1999.
We operate an “astrometry engine” to create correct, standards-based astrometric headers for every useful astronomical image ever taken, past and future, in any state of archival disarray.
The Dark Energy Spectroscopic Instrument Survey (DESI) is a five-year program aimed at mapping the distribution of galaxies and neutral gas over the redshift range 0 < z < 3. The goal of the program is to make measurements of the growth and expansion histories of the universe. Observations are taken on the 4-meter Mayall Telescope at Kitt Peak National Observatory. A single field yields 5000 fiber-optic spectra, which are set using robotic fiber positioners. This system allows rapid cadence of observations, enabling the survey to cover 14,000 square degrees every year in dark time. The dark time program will target luminous red galaxies at z ~ 0.8, emission-line galaxies at z ~ 1.3, QSOs at z ~ 2, and Lyman-alpha forest quasars up to z ~ 3. In all, the dark time program will yield 20 million galaxy and quasar redshifts.
The full survey is described in this document. For more information about the collaboration, see the DESI public web page. NYU has two faculty members in the DESI collaboration.
Anthony Pullen: Professor Pullen’s interests in the DESI program include the ELG and quasar surveys, expressed in a few projects. One is to improve automated redshift estimates for the ELG survey. Another is to test Einstein’s gravitational theory of general relativity using measurements of growth of structure including gravitational lensing and redshift-space distortions A third project is to measure the intensity of diffuse galaxy emission by correlating maps of DESI galaxies and quasars with large-scale line intensity mapping surveys, such as EXCLAIM. These measurements will probe star formation and galaxy evolution in the Universe.
Jeremy Tinker: Professor Tinker is focused on the DESI program during bright time, called the Bright Galaxy Survey (BGS). The BGS is a magnitude limited survey that will yield 20 million galaxy redshifts at z < 0.4. The magnitude limit is r=20, making it more than 2 magnitudes fainter than the SDSS main galaxy sample. Thus, BGS will yield a sample with a cosmologically-relevant volume, but with a high density sampling of the galaxy distribution. This sample is ideal for studying the galaxy-halo connection, both for the purpose of constraining cosmology at non-linear scales, and understanding the physics of galaxy formation.
The Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx) is a NASA Medium Explorer mission designed to 1) constrain the physics of inflation by measuring its imprints on the three-dimensional large-scale distribution of matter, 2) trace the history of galactic light production through a deep multi-band measurement of large-scale clustering, and 3) investigate the abundance and composition of water and biogenic ices in the early phases of star and planetary disk formation. SPHEREx will obtain near-infrared 0.75 – 5.0 um spectra every 6″ over the entire sky. It implements a simple instrument design with a single observing mode to map the entire sky four times during its nominal 25-month mission. SPHEREx will also have strong scientific synergies with other missions and observatories, resulting in a rich legacy archive of spectra that will bear on numerous scientific investigations.
Anthony Pullen: Professor Pullen’s interests in the SPHEREx program involve using the cosmic infrared background and line intensity maps from the survey to probe star formation and galaxy evolution. In addition, he will seek to cross-correlate SPHEREx’s galaxy survey with various intensity maps such as from EXCLAIM to better connect galaxy evolution with large-scale structure.
The EXperiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) is a balloon-borne mission to measure the late cosmic star formation history up to redshifts z=3.5. This mission will use the line intensity mapping technique to detect the ladder of emission lines from carbon monoxide (CO) (0 < z < 0.9) and ionized carbon [C+] emission (2.5 < z < 3.5), global tracers of star formation. These sources of extragalactic emission will be mapped over 400 deg2 away from the Galactic Plane. The mission will also map [CI] emission from the Milky Way Galaxy over 90 deg2 in order to help connect CO and H2 emission in order to better trace star formation. Observations will be performed by a telescope cooled to 1.5 K on a balloon floating at 120,000 ft (36 km), which each survey lasting one night (9 hours). The full survey is described in this document. NYU has one faculty member in the collaboration.
Anthony Pullen: Professor Pullen is the Science Lead for the EXCLAIM mission. His role is focused on constructing the science pipeline for the survey. The first item is to construct the model relating the emission of the various lines to properties of star formation and galaxy evolution. The second is to build the machinery to convert line intensity maps to measurements of these properties. The third is to mitigate the effect of foreground emission for the galaxy to necessary requirements.