Publications (62)
Searching for stable fullerenes in space with computational chemistry
Alessandra Candian, Marina Gomes Rachid, Heather MacIsaac +3
We report a computational study of the stability and infrared (IR) vibrational spectra of neutral and singly ionised fullerene cages containing between 44 and 70 carbon atoms. The…
The EDIBLES survey IV. Cosmic ray ionization rates in diffuse clouds from near-ultraviolet observations of interstellar OH
Xavier L. Bacalla, Harold Linnartz, Nick L. J. Cox +6
We report cosmic ray ionization rates towards ten reddened stars studied within the framework of the EDIBLES (ESO Diffuse Interstellar Bands Large Exploration Survey) program, usin…
Detection of C Combination Bands in the Near-IR Spectrum of Tc 1
Morgan M. Giese, Vincent J. Esposito, Simon Van Schuylenbergh +26
We report the detection of a set of new near-infrared emission features between 3.5 and 5.2 m in JWST/NIRSpec observations of Tc 1, the planetary nebula known for displaying th…
PDRs4All: XVIII. The evolution of the PAH ionisation and PAH size distribution across the Orion Bar
Alexandros Maragkoudakis, Christiaan Boersma, Els Peeters +25
We investigate the evolution of the PAH population's charge state and size across key physical zones in the Orion Bar, which include the HII region, the atomic PDR (APDR), and thre…
The formation of cosmic fullerenes from arophatic clusters
Elisabetta R. Micelotta, Anthony P. Jones, Jan Cami +3
Fullerenes have recently been identified in space and they may play a significant role in the gas and dust budget of various astrophysical objects including planetary nebulae (PNe)…
The messy death of a multiple star system and the resulting planetary nebula as observed by JWST
Orsola De Marco, Muhammad Akashi, Stavros Akras +66
Planetary nebulae (PNe), the ejected envelopes of red giant stars, provide us with a history of the last, mass-losing phases of 90 percent of stars initially more massive than the…
The ESO Diffuse Interstellar Bands Large Exploration Survey: EDIBLES I. Project description, survey sample and quality assessment
Nick Cox, Jan Cami, Amin Farhang +27
The carriers of the diffuse interstellar bands (DIBs) are largely unidentified molecules ubiquitously present in the interstellar medium (ISM). After decades of study, two strong a…
PDRs4All XIII. Empirical prescriptions for the interpretation of JWST imaging observations of star-forming regions
Ryan Chown, Yoko Okada, Els Peeters +17
(Abridged) JWST continues to deliver incredibly detailed infrared (IR) images of star forming regions in the Milky Way and beyond. IR emission from star-forming regions is very spe…
JWST observations of the Ring Nebula (NGC 6720): I. Imaging of the rings, globules, and arcs
R. Wesson, Mikako Matsuura, Albert A. Zijlstra +18
We present JWST images of the well-known planetary nebula NGC 6720 (the Ring Nebula), covering wavelengths from 1.6m to 25 m. The bright shell is strongly fragmented with s…
The Detailed Science Case for the Maunakea Spectroscopic Explorer, 2019 edition
The MSE Science Team, Carine Babusiaux, Maria Bergemann +258
(Abridged) The Maunakea Spectroscopic Explorer (MSE) is an end-to-end science platform for the design, execution and scientific exploitation of spectroscopic surveys. It will unvei…
Spectroscopic detection of Carbon Monoxide in the Young Supernova Remnant Cassiopeia A
Jeonghee Rho, Takashi Onaka, Jan Cami +1
We report the detection of carbon monoxide (CO) emission from the young supernova remnant Cassiopeia A (Cas A) at wavelengths corresponding to the fundamental vibrational mode at 4…
PDRs4All II: JWST's NIR and MIR imaging view of the Orion Nebula
Emilie Habart, Els Peeters, Olivier Berné +139
The JWST has captured the most detailed and sharpest infrared images ever taken of the inner region of the Orion Nebula, the nearest massive star formation region, and a prototypic…
Families and Clusters of Diffuse Interstellar Bands: a Data-Driven Correlation Analysis
Haoyu Fan, Madison Schwartz, Amin Farhang +9
More than 500 diffuse interstellar bands (DIBs) have been observed in astronomical spectra, and their signatures and correlations in different environments have been studied over t…
Detection of CO ice in the planetary nebula NGC 6302
Charmi Bhatt, Simon W. Cao, Jan Cami +20
Using JWST/MIRI observations, we report the detection of CO ice in the dusty torus of the planetary nebula NGC 6302, an environment generally considered hostile to fragile mole…
LRP2020: Astrostatistics in Canada
Gwendolyn Eadie, Arash Bahramian, Pauline Barmby +16
(Abridged from Executive Summary) This white paper focuses on the interdisciplinary fields of astrostatistics and astroinformatics, in which modern statistical and computational me…
The molecular and dusty composition of Betelgeuse's inner circumstellar environment
Guy Perrin, Tijl Verhoelst, Stephen T. Ridgway +6
The study of the atmosphere of red supergiant stars in general and of Betelgeuse (alpha Orionis) in particular is of prime importance to understand dust formation and how mass is l…
Observation of an Accreting Planetary-Mass Companion with Signs of Disk-Disk Interaction in Orion
Emilie Vila, Paul Amiot, Olivier Berné +11
Young ( Myr) planetary-mass companions (PMCs) provide valuable insights into the formation and early evolution of planetary systems. To date, only a dozen such objects…
Formation of the Methyl Cation by Photochemistry in a Protoplanetary Disk
Olivier Berné, Marie-Aline Martin-Drumel, Ilane Schroetter +53
Forty years ago it was proposed that gas phase organic chemistry in the interstellar medium was initiated by the methyl cation CH3+, but hitherto it has not been observed outside t…
A Principal Component Analysis of polycyclic aromatic hydrocarbon emission in NGC 2023
Ameek Sidhu, Els Peeters, Jan Cami +1
We use the measured fluxes of polycyclic aromatic hydrocarbon (PAH) emission features at 6.2, 7.7, 8.6, 11.0 and 11.2 m in the reflection nebula NGC 2023 to carry out a princip…
Detection of CH3+ in the O-rich planetary nebula NGC 6302
Charmi Bhatt, Jan Cami, Els Peeters +33
Planetary nebulae are sites where ejected stellar material evolves into complex molecules, but the precise physical conditions and chemical routes that govern these processes are u…
OH as a probe of the warm water cycle in planet-forming disks
Marion Zannese, Benoît Tabone, Emilie Habart +52
Water is a key ingredient for the emergence of life as we know it. Yet, its destruction and reformation in space remains unprobed in warm gas. Here, we detect the hydroxyl radical…
Perspectives on Astrophysics Based on Atomic, Molecular, and Optical (AMO) Techniques
Daniel Wolf Savin, James F. Babb, Paul M. Bellan +35
About two generations ago, a large part of AMO science was dominated by experimental high energy collision studies and perturbative theoretical methods. Since then, AMO science has…
PDRs4All IV. An embarrassment of riches: Aromatic infrared bands in the Orion Bar
Ryan Chown, Ameek Sidhu, Els Peeters +136
(Abridged) Mid-infrared observations of photodissociation regions (PDRs) are dominated by strong emission features called aromatic infrared bands (AIBs). The most prominent AIBs ar…
ISO Mid-Infrared Spectroscopy of Galactic Bulge AGB Stars
Joris A. D. L. Blommaert, Martin A. T. Groenewegen, Koryo Okumura +8
To study the nature of Bulge AGB stars and in particular their circumstellar dust, we have analysed mid-infrared spectra obtained with the ISOCAM CVF spectrometer in three Bulge fi…
A far-ultraviolet-driven photoevaporation flow observed in a protoplanetary disk
Olivier Berné, Emilie Habart, Els Peeters +143
Most low-mass stars form in stellar clusters that also contain massive stars, which are sources of far-ultraviolet (FUV) radiation. Theoretical models predict that this FUV radiati…
Fullerenes in circumstellar and interstellar environments
Jan Cami
In recent years, the fullerene species C60 (and to a lesser extent also C70) has been reported in the mid-IR spectra of various astronomical objects. Cosmic fullerenes form in the…
Polycyclic Aromatic Hydrocarbon emission model in photodissociation regions I: Application to the 3.3, 6.2, and 11.2 m bands
Ameek Sidhu, A. G. G. M. Tielens, Els Peeters +1
We present a charge distribution based model that computes the infrared spectrum of polycyclic aromatic hydrocarbon (PAH) molecules using recent measurements or quantum chemical ca…
The Gas-Rich Circumbinary Disk of HR 4049. II: A Detailed Study of the Near-Infrared Spectrum
Sarah E. Malek, Jan Cami
HR 4049 is a peculiar evolved binary which is surrounded by a circumbinary disk. Mid-infrared observations show that the disk is rich in molecular gas and radially extended. To stu…
Solar C/O ratio in planet-forming gas at 1 au in a highly irradiated disk
Ilane Schroetter, Olivier Berné, Emeric Bron +18
The chemical composition of exoplanets is thought to be influenced by the composition of the disks in which they form. JWST observations have unveiled a variety of species in numer…
Searching for Corannulene with ALMA: Observations of the Red Rectangle Nebula
Elise Koo, Alessandra Candian, Michiel Hogerheijde +6
Polycyclic Aromatic Hydrocarbons (PAHs) are organic molecules responsible for the Aromatic Infrared Bands (AIBs), observed across a multitude of astrophysical environments. Despite…
PDRs4All XXII. Near-Infrared continuum in the Orion Bar
Takashi Onaka, Emmanuel Dartois, Els Peeters +13
Conspicuous excess emission is present in the near-infrared (NIR) region in various objects, including reflection nebulae, planetary nebulae, and nearby galaxies. However, the spat…
Extended Dust Emission from Nearby Evolved Stars
Thavisha E. Dharmawardena, Francisca Kemper, Peter Scicluna +6
We present JCMT SCUBA-2 m and m observations of 14 Asymptotic Giant Branch (AGB) stars (9 O--rich, 4 C-rich and 1 S--type) and one Red Supergiant (RSG) in the Solar N…
The EDIBLES survey VI. Searching for time variations of interstellar absorption features
Amin Farhang, Jonathan Smoker, Nick L. J. Cox +10
Interstellar lines observed toward stellar targets change slowly over long timescales, mainly due to the proper motion of the background target relative to the intervening clouds.…
Polycyclic aromatic hydrocarbon emission toward the Galactic bulge
Matthew J. Shannon, Els Peeters, Jan Cami +1
We examine polycyclic aromatic hydrocarbon (PAH), dust and atomic/molecular emission toward the Galactic bulge using Spitzer Space Telescope observations of four fields: C32, C35,…
PDRs4All XIX. The 6 to 9 m region as a probe of PAH charge and size in the Orion Bar
Baria Khan, Samuel A. Daza Rodriguez, Els Peeters +24
Infrared emission from polycyclic aromatic hydrocarbons (PAHs) play a major role in determining the charge balance of their host environments that include photo-dissociation region…
A Study of Polycyclic Aromatic Hydrocarbon Emission in 30 Dor as seen by JWST
Congcong Zhang, Joelene Hales, Els Peeters +3
Polycyclic aromatic hydrocarbons (PAHs) are responsible for strong mid-IR emission features near star-forming regions. It is well known that low-metallicity environments exhibit we…
Stellar Astrophysics and Exoplanet Science with the Maunakea Spectroscopic Explorer (MSE)
Maria Bergemann, Daniel Huber, Vardan Adibekyan +70
The Maunakea Spectroscopic Explorer (MSE) is a planned 11.25-m aperture facility with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. A…
PDRs4All: A JWST Early Release Science Program on radiative feedback from massive stars
Olivier Berné, Ãmilie Habart, Els Peeters +134
Massive stars disrupt their natal molecular cloud material through radiative and mechanical feedback processes. These processes have profound effects on the evolution of interstell…
The Astropy Problem
Demitri Muna, Michael Alexander, Alice Allen +151
The Astropy Project (http://astropy.org) is, in its own words, "a community effort to develop a single core package for Astronomy in Python and foster interoperability between Pyth…
The close circumstellar environment of Betelgeuse - Adaptive optics spectro-imaging in the near-IR with VLT/NACO
Pierre Kervella, Tijl Verhoelst, Stephen T. Ridgway +4
Context: Betelgeuse is one the largest stars in the sky in terms of angular diameter. Structures on the stellar photosphere have been detected in the visible and near-infrared as w…
PDRs4All XVI. Tracing aromatic infrared band characteristics in photodissociation region spectra with PAHFIT in the JWST era
Dries Van De Putte, Els Peeters, Karl D. Gordon +13
Photodissociation regions (PDRs) exhibit emission between 3-20 um known as the Aromatic Infrared Bands (AIBs), originating from small carbonaceous species such as polycyclic aromat…
The close circumstellar environment of Betelgeuse - II. Diffraction-limited spectro-imaging from 7.76 to 19.50 microns with VLT/VISIR
Pierre Kervella, Guy Perrin, Andrea Chiavassa +4
Context: Mass-loss occurring in red supergiants (RSGs) is a major contributor to the enrichment of the interstellar medium in dust and molecules. The physical mechanism of this mas…
PDRs4All III: JWST's NIR spectroscopic view of the Orion Bar
Els Peeters, Emilie Habart, Olivier Berne +135
(Abridged) We investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the HII region to the atomic PDR (crossing the i…
The Gas-Rich Circumbinary Disk of HR 4049 I: A Detailed Study of the Mid-Infrared Spectrum
Sarah E. Malek, Jan Cami
We present a detailed analysis of the mid-infrared spectrum of the peculiar evolved object HR 4049. The full Spitzer-IRS high-resolution spectrum shows a wealth of emission with pr…
JWST observations of the Ring Nebula (NGC 6720): III. A dusty disk around its Central Star
Raghvendra Sahai, Griet Van de Steene, Peter van Hoof +16
The planetary nebula NGC 6720, also known as the ``Ring Nebula", is one of the most iconic examples of nearby planetary nebulae whose morphologies present a challenge to our theore…
The EDIBLES survey V: Line profile variations in the 5797, 6379, and 6614 diffuse interstellar bands as a tool to constrain carrier sizes
Heather MacIsaac, Jan Cami, Nick L. J. Cox +13
Several diffuse interstellar bands (DIBs) have profiles with resolved sub-peaks that resemble rotational bands of large molecules. Analysis of these profiles can constrain the size…
A sensitive spectral survey of interstellar features in the near-UV [3050-3700Ã ]
Neil Hemant Bhatt, Jan Cami
We present a comprehensive and sensitive unbiased survey of interstellar features in the near-UV range (3050-3700 Ã ). We combined a large number of VLT/UVES archival observations…
PDRs4All VIII: Mid-IR emission line inventory of the Orion Bar
Dries Van De Putte, Raphael Meshaka, Boris Trahin +135
Mid-infrared emission features probe the properties of ionized gas, and hot or warm molecular gas. The Orion Bar is a frequently studied photodissociation region (PDR) containing l…
The Rich Circumstellar Chemistry of SMP LMC 11
Sarah E. Malek, Jan Cami, Jeronimo Bernard-Salas
Carbon-rich evolved stars from the asymptotic giant branch to the planetary nebula phase are characterized by a rich and complex carbon chemistry in their circumstellar envelopes.…
Fullerenes in circumstellar and interstellar environments
Jan Cami, Jeronimo Bernard-Salas, Els Peeters +1
We recently identified several emission bands in the Spitzer-IRS spectrum of the unusual planetary nebula Tc 1 with the infrared active vibrational modes of the neutral fullerene s…
Application of the emission model to PAHs and C II.Polycyclic Aromatic Hydrocarbon emission model in photodissociation regions
Ameek Sidhu, A. G. G. M. Tielens, Els Peeters +1
We present a charge distribution-based emission model that calculates the infrared spectrum of fullerenes (C). Analysis of the modelled spectrum of C in various charg…
The Submillimetre Universe
Douglas Scott, Pauline Barmby, Pierre Bastien +19
Submillimetre continuum radiation allows us to probe cold objects, particularly the earliest, dusty phases of star formation, high-redshift galaxies and circumstellar disks. The su…
The JWST/MIRI view of the planetary nebula NGC 6302 I.: a UV irradiated torus and a hot bubble triggering PAH formation
Mikako Matsuura, Kevin Volk, Patrick Kavanagh +34
NGC 6302 is a spectacular bipolar planetary nebula (PN) whose spectrum exhibits fast outflows and highly ionized emission lines, indicating the presence of a very hot central star…
Are the Carriers of Diffuse Interstellar Bands and Extended Red Emission the same?
Thomas S. -Y. Lai, Adolf N. Witt, Carlos Alvarez +1
We report the first spectroscopic observations of a background star seen through the region between the ionization front and the dissociation front of the nebula IC 63. This photod…
A Principal component analysis of the diffuse interstellar bands
Tiffany Ensor, Jan Cami, Neil H. Bhatt +1
We present a principal component analysis of 23 line of sight parameters (including the strengths of 16 diffuse interstellar bands, DIBs) for a well-chosen sample of single-cloud s…
Characterisation of the Planetary Nebula Tc 1 Based on VLT X-Shooter Observations
Isabel Aleman, Marcelo L. Leal-Ferreira, Jan Cami +11
We present a detailed analysis of deep VLT/X-Shooter observations of the planetary nebula Tc 1. We calculate gas temperature, density, extinction, and abundances for several specie…
JWST observations of the Ring Nebula (NGC 6720) -- II. PAH emission
Nicholas Clark, Els Peeters, Nick L. J. Cox +16
Polycyclic aromatic hydrocarbons (PAHs) and carbonaceous dust have been observed in clumpy circumstellar environments, yet their formation and evolutionary pathways in such environ…
C diffuse interstellar band correlations and environmental variations
Leander Schlarmann, Bernard Foing, Jan Cami +1
The Diffuse Interstellar Bands (DIBs) are absorption features seen in the spectra of astronomical objects, that arise in the interstellar medium. Today more than 500 DIBs have been…
The Nearby Evolved Stars Survey: I. JCMT/SCUBA-2 Sub-millimetre detection of the detached shell of U Antliae
Thavisha E. Dharmawardena, Francisca Kemper, Sundar Srinivasan +24
We present the highest resolution single-dish submillimetre observations of the detached shell source U Antliae to date. The observations were obtained at $450~\micron$ and $850~\m…
A Principal Component Analysis of polycyclic aromatic hydrocarbon emission in NGC 7023
Ameek Sidhu, Josh Bazely, Els Peeters +1
We carried out a principal component analysis (PCA) of the fluxes of five polycyclic aromatic hydrocarbon (PAH) bands at 6.2, 7.7, 8.6, 11.0, and 11.2 m in the reflection nebul…
Canadian Investigations of the Interstellar Medium
Alex S. Hill, Jan Cami, Laura Fissel +10
The interstellar medium mediates galactic evolution as the reservoir of material for future star formation and the repository of energy and matter output by stellar processes. Cana…
The EDIBLES Survey. VII. A survey of C2 and C3 in interstellar clouds
Haoyu Fan, Carlos M. R. Rocha, Martin Cordiner +14
We carried out a sensitive survey of C and C using the EDIBLES data set. We also expanded our searches to C, C, and CC isotopologue in the most molecu…