Search Publications
Rapid mid-infrared spectral timing with JWST: GRS 1915+105 during an MIR-bright and X-ray-obscured state
Maccarone, T. J.; Altamirano, D.; Knigge, C. +45 more
We present mid-infrared (MIR) spectral-timing measurements of the prototypical Galactic microquasar GRS 1915+105. The source was observed with the Mid-Infrared Instrument (MIRI) onboard JWST in June 2023 at an MIR luminosity
Cosmic star-formation history and black hole accretion history inferred from the JWST mid-infrared source counts
Kilerci, Ece; Hashimoto, Tetsuya; Goto, Tomotsugu +7 more
With the advent of the JWST, extragalactic source count studies were conducted down to sub-µJy in the mid-infrared (MIR), which is several tens of times fainter than what the previous-generation infrared (IR) telescopes achieved in the MIR. In this work, we aim to interpret the JWST source counts and constrain cosmic star-formation history (…
Oxygen abundance of γ Vel from [O III] 88 µm Herschel/PACS spectroscopy
Hillier, D. J.; Morris, P. W.; Barlow, M. J. +4 more
We present Herschel PACS spectroscopy of the [O III] 88.4 µm fine-structure line in the nearby WC8+O binary system γ Vel to determine its oxygen abundance. The critical density of this line corresponds to several 105R* such that it is spatially extended in PACS observations at the 336 pc distance to γ Vel. Two approache…
Modelling JWST mid-infrared counts: excellent consistency with models derived for IRAS, ISO, and Spitzer
Rowan-Robinson, Michael
Models derived in 2009 to fit mid-infrared (8-24 micron) source counts from the IRAS, ISO, and Spitzer missions, provide an excellent fit to deep counts with JWST, demonstrating that the evolution of dusty star-forming galaxies is well understood. The evolution of dust in galaxies at high redshifts is discussed and a simple prescription is propose…
Source counts at 7.7-21 µm in CEERS field with JWST
Kilerci, Ece; Hashimoto, Tetsuya; Goto, Tomotsugu +8 more
Source counts - the number density of sources as a function of flux density - represent one of the fundamental metrics in observational cosmology due to their straightforward and simple nature. It is an important tool that provides information on galaxy formation and evolution. Source counting is a direct measurement. Compared to advanced analyses…
Evolution of grain size distribution with enhanced abundance of small carbonaceous grains in galactic environments
Hirashita, Hiroyuki
We propose an updated dust evolution model that focuses on the grain size distribution in a galaxy. We treat the galaxy as a one-zone object and include five main processes (stellar dust production, dust destruction in supernova shocks, grain growth by accretion and coagulation, and grain disruption by shattering). In this paper, we improve the pr…
Multiple gas phases in supernova remnant IC 443: mapping shocked H2 with VLT/KMOS
Fang, Min; Chen, Zhiwei; Bian, Fuyan +8 more
Supernovae and their remnants provide energetic feedback to the ambient interstellar medium (ISM), which is often distributed in multiple gas phases. Among them, warm molecular hydrogen (H2) often dominates the cooling of the shocked molecular ISM, which has been observed with the H2 emission lines at near-infrared wavelength…
Carbonates and ices in the z = 0.89 galaxy-absorber towards PKS 1830-211 and within star-forming regions of the Milky Way
Bowey, Janet E.
A pair of 6.0 and 6.9 µm absorption features are frequently observed in Milky Way (MW) molecular-clouds and YSOs; they also occur in the z = 0.886 rest-frame of a molecule-rich spiral galaxy obscuring blazar PKS 1830-211. I calibrate χ2-fitting methods, which match observations with two or three laboratory spectra. The 6.0-µ…
Light and colour of cirrus, translucent, and opaque dust in the high-latitude area of LDN 1642
Haas, M.; Väisänen, P.; Lehtinen, K. +2 more
We have performed a 5-colour surface photometric study of the high-galactic-latitude area of dark nebula LDN 1642. Scattered light properties are presented of diffuse, translucent, and opaque dust over the range of 3500-5500 Å . Far infrared absolute photometry at 200 µm improves the precision of and provides a zero point to the extinction. The in…
A photodissociation region (PDR) model grid in planetary nebula paradigm: dependency of C and O fine structure line emission and PDR thermal structure on central star radiation and nebular dust composition
Das, Ramkrishna; Bandyopadhyay, Rahul
We compute a grid of photodissociation region (PDR) models. The varying parameters of the grid include effective temperature (Teff) and luminosity (L) of the radiation source, density (nH) of the nebula, PDR depth from the nebular ionization front (ΔrPDR), and densities of polycyclic aromatic hydrocarbon (PAH) mole…