Search Publications
Expanded Sample of Small Magellanic Cloud Ultraviolet Dust Extinction Curves: Correlations between the 2175 Å Bump, q PAH, Ultraviolet Extinction Shape, and N(H I)/A(V)
Murray, Claire E.; Gordon, Karl D.; Fitzpatrick, E. L. +7 more
The Small Magellanic Cloud (SMC) shows a large variation in ultraviolet (UV) dust extinction curves, ranging from Milky Way (MW) like to significantly steeper curves with no detectable 2175 Å bump. This result is based on a sample of only nine sight lines. From Hubble Space Telescope Space Telescope Imaging Spectrograph and IUE spectra of OB stars…
Black Hole Spin Measurements in LMC X-1 and Cyg X-1 Are Highly Model Dependent
Zdziarski, Andrzej A.; Szanecki, Michał; Dewangan, Gulab +4 more
The black hole spin parameter, a *, was measured to be close to its maximum value of 1 in many accreting X-ray binaries. In particular, a * ≳ 0.9 was found in a number of studies of LMC X-1. These measurements were claimed to take into account both statistical and systematic uncertainties. We perform new measurements using a …
SMILES: A Prototype JWST Multiband Mid-infrared Survey
Shivaei, Irene; Lyu, Jianwei; Alberts, Stacey +4 more
The Mid-Infrared Instrument (MIRI) for JWST is supplied with a suite of imaging band-pass filters optimized for full spectral coverage in eight intermediate-width bands from 5 to 26 µm and a narrower one at 11.3 µm. This contrasts with previous infrared space telescopes, which generally have provided only two broad bands, one near 10 &…
Molecular Outflow in the Reionization-epoch Quasar J2054-0005 Revealed by OH 119 µm Observations
Fujimoto, Seiji; Inoue, Akio K.; Hashimoto, Takuya +8 more
Molecular outflows are expected to play a key role in galaxy evolution at high redshift. To study the impact of outflows on star formation at the epoch of reionization, we performed sensitive Atacama Large Millimeter/submillimeter Array observations of OH 119 µm toward J2054-0005, a luminous quasar at z = 6.04. The OH line is detected and ex…
Detection of X-Ray Polarization from the Blazar 1ES 1959+650 with the Imaging X-Ray Polarimetry Explorer
Ingram, Adam; Kaaret, Philip; Wu, Kinwah +142 more
Observations of linear polarization in the 2–8 keV energy range with the Imaging X-ray Polarimetry Explorer (IXPE) explore the magnetic field geometry and dynamics of the regions generating nonthermal radiation in relativistic jets of blazars. These jets, particularly in blazars whose spectral energy distribution peaks at X-ray energies, emit X-ra…
A Comprehensive Investigation of Metals in the Circumgalactic Medium of Nearby Dwarf Galaxies
McQuinn, Kristen B. W.; Burchett, Joseph N.; Putman, Mary E. +7 more
Dwarf galaxies are found to have lost most of their metals via feedback processes; however, there still lacks consistent assessment on the retention rate of metals in their circumgalactic medium (CGM). Here we investigate the metal content in the CGM of 45 isolated dwarf galaxies with M * = 106.5-9.5 M ⊙ (M 20…
Properties of an Interplanetary Shock Observed at 0.07 and 0.7 au by Parker Solar Probe and Solar Orbiter
Zank, Gary P.; Zhao, Lingling; Karlsson, Tomas +23 more
The Parker Solar Probe (PSP) and Solar Orbiter (SolO) missions opened a new observational window in the inner heliosphere, which is finally accessible to direct measurements. On 2022 September 5, a coronal mass ejection (CME)-driven interplanetary (IP) shock was observed as close as 0.07 au by PSP. The CME then reached SolO, which was radially wel…
High-redshift, Small-scale Tests of Ultralight Axion Dark Matter Using Hubble and Webb Galaxy UV Luminosities
Hložek, Renée; Marsh, David J. E.; Winch, Harrison +1 more
We calculate the abundance of UV-bright galaxies in the presence of ultralight axion (ULA) dark matter (DM), finding that axions suppress their formation with a non-trivial dependence on redshift and luminosity. We set limits on axion DM using UV luminosity function (UVLF) data, excluding a single axion as all the DM for m ax < 10
IPA: Class 0 Protostars Viewed in CO Emission Using JWST
Manoj, P.; Narang, Mayank; Bourke, Tyler L. +24 more
We investigate the bright CO fundamental emission in the central regions of five protostars in their primary mass assembly phase using new observations from JWST's Near-Infrared Spectrograph and Mid-Infrared Instrument. CO line emission images and fluxes are extracted for a forest of ∼150 rovibrational transitions from two vibrational bands, v = 1…
Dynamical Stellar Mass-to-light Ratio Gradients: Evidence for Very Centrally Concentrated IMF Variations in ETGs?
Bender, Ralf; Thomas, Jens; Erwin, Peter +4 more
Evidence from different probes of the stellar initial mass function (IMF) of massive early-type galaxies (ETGs) has repeatedly converged on IMFs more bottom heavy than in the Milky Way (MW). This consensus has come under scrutiny due to often contradictory results from different methods on the level of individual galaxies. In particular, a number …