Publications (43)
Complexity reduction of astrochemical networks
T. Grassi, S. Bovino, F. A. Gianturco +2
We present a new computational scheme aimed at reducing the complexity of the chemical networks in astrophysical models, one which is shown to markedly improve their computational…
The formation of massive primordial stars in the presence of moderate UV backgrounds
M. A. Latif, D. R. G. Schleicher, S. Bovino +2
Radiative feedback from populations II stars played a vital role in early structure formation. Particularly, photons below the Lyman limit can escape the star forming regions and p…
Modelling thermochemical processes in protoplanetary disks I: numerical methods
T. Grassi, B. Ercolano, L. Szűcs +2
The dispersal phase of planet-forming disks via winds driven by irradiation from the central star and/or magnetic fields in the disk itself is likely to play an important role in t…
A UV flux constraint on the formation of direct collapse black holes
M. A. Latif, S. Bovino, C. Van Borm +3
The ability of metal free gas to cool by molecular hydrogen in primordial halos is strongly associated with the strength of ultraviolet (UV) flux produced by the stellar population…
Testing analytical methods to derive the cosmic-ray ionisation rate in cold regions via synthetic observations
E. Redaelli, S. Bovino, A. Lupi +4
Cosmic rays (CRs) heavily impact the chemistry and physics of cold and dense star-forming regions. However, characterising their ionisation rate is still challenging from an observ…
A detailed framework to incorporate dust in hydrodynamical simulations
T. Grassi, S. Bovino, T. Haugboelle +1
Dust plays a key role in the evolution of the ISM and its correct modelling in numerical simulations is therefore fundamental. We present a new and self-consistent model that treat…
New Estimate for the Cosmic Ray-Induced Photodissociation Rate in the Interstellar Medium
O. Sipilä, P. Caselli, M. Padovani +5
In the interstellar medium, cosmic rays (CRs) generate a field of ultraviolet (UV) photons via the excitation and subsequent radiative decay of molecules. This UV field i…
Modeling the role of electron attachment rates on column density ratios for CnH-/CnH (n=4,6,8) in dense molecular clouds
F. A. Gianturco, T. Grassi, R. Wester
(abridged) The fairly recent detection of a variety of anions in the Interstellar Molecular Clouds have underlined the importance of realistically modeling the processes governing…
CH+ depletion by atomic hydrogen: accuracy of new rates in photo-dominated and self-shielded environments
S. Bovino, T. Grassi, M. Tacconi +1
A detailed quantum analysis of a ionic reaction with a crucial role in the ISM is carried out to generate ab initio reactive cross sections with a quantum method. From them we obta…
Formation of carbon-enhanced metal-poor stars in the presence of far ultraviolet radiation
S. Bovino, T. Grassi, D. R. G. Schleicher +1
Recent discoveries of carbon-enhanced metal-poor stars like SMSS J031300.36-670839.3 provide increasing observational insights into the formation conditions of the first second-gen…
Formation and Evolution of the Dust in Galaxies. III. The Disk of the Milky Way
L. Piovan, C. Chiosi, E. Merlin +4
Models of chemical evolution of galaxies including the dust are nowadays required to decipher the high-z universe. In a series of three papers we have tackled the problem and set a…
Effects of turbulence and rotation on protostar formation as a precursor to seed black holes
C. Van Borm, S. Bovino, M. A. Latif +3
Context. The seeds of the first supermassive black holes may have resulted from the direct collapse of hot primordial gas in K haloes, forming a supermassive or quas…
Planet Formation and Disk Chemistry: Dust and Gas Evolution during Planet Formation
G. Perotti, L. Cacciapuoti, N. -D. Tung +3
Over the past decade, progress in observational capabilities, combined with theoretical advancements, have transformed our comprehension of the physics and chemistry during planet…
A novel framework to study the impact of binding energy distributions on the chemistry of dust grains
T. Grassi, S. Bovino, P. Caselli +3
The evaporation of molecules from dust grains is crucial to understand some key aspects of the star- and the planet-formation processes. During the warm-up phase the presence of yo…
Dark-matter halo mergers as a fertile environment for low-mass Population III star formation
S. Bovino, M. A. Latif, T. Grassi +1
While Population III stars are typically thought to be massive, pathways towards lower-mass Pop III stars may exist when the cooling of the gas is particularly enhanced. A possible…
Formation and Evolution of the Dust in Galaxies. I. The Condensation Efficiencies
L. Piovan, C. Chiosi, E. Merlin +4
The growing interest in the high-z universe, where strongly obscured objects are present, has determined an effort to improve the simulations of dust formation and evolution in gal…
Mapping Synthetic Observations to Prestellar Core Models: An Interpretable Machine Learning Approach
T. Grassi, M. Padovani, D. Galli +6
Observations of molecular lines are a key tool to determine the main physical properties of prestellar cores. However, not all the information is retained in the observational proc…
Chemical complexity in astrophysical simulations: optimization and reduction techniques
T. Grassi, S. Bovino, D. Schleicher +1
Chemistry has a key role in the evolution of the interstellar medium (ISM), so it is highly desirable to follow its evolution in numerical simulations. However, it may easily domin…
KROME - a package to embed chemistry in astrophysical simulations
T. Grassi, S. Bovino, D. R. G. Schleicher +4
Chemistry plays a key role in many astrophysical situations regulating the cooling and the thermal properties of the gas, which are relevant during gravitational collapse, the evol…
How realistic UV spectra and X-rays suppress the abundance of direct collapse black holes
M. A. Latif, S. Bovino, T. Grassi +2
Observations of high redshift quasars at indicate that they harbor supermassive black holes (SMBHs) of a billion solar masses. The direct collapse scenario has emerged as the…
A 3D physico-chemical model of a pre-stellar core. I. Environmental and structural impact on the distribution of CHOH and -CH
S. S. Jensen, S. Spezzano, P. Caselli +2
Pre-stellar cores represent the earliest stage of the star- and planet-formation process. By characterizing the physical and chemical structure of these cores we can establish the…
MaNN: Multiple Artificial Neural Networks for modelling the Interstellar Medium
T. Grassi, E. Merlin, L. Piovan +2
Modelling the complex physics of the Interstellar Medium (ISM) in the context of large-scale numerical simulations is a challenging task. A number of methods have been proposed to…
Performance of the CMS Zero Degree Calorimeters in pPb collisions at the LHC
O. Surányi, A. Al-Bataineh, J. Bowen +19
The two Zero Degree Calorimeters (ZDCs) of the CMS experiment are located at m from the collision point and detect neutral particles in the pseudorapidity re…
Formation and Evolution of the Dust in Galaxies. II. The Solar Neighbourhood
L. Piovan, C. Chiosi, E. Merlin +4
Over the past decade a new generation of chemical models have included the dust in the treatment of the ISM. This major accomplishment has been spurred by the growing amounts of da…
A differentiable and optimizable 3D model for interpretation of observed spectral data cubes
T. Grassi, J. E. Pineda, S. Spezzano +6
Molecular spectral cubes of prestellar cores encode the information on the physical and chemical properties of these objects along the line of sight. To retrieve this information,…
Interpreting molecular hydrogen and atomic oxygen line emission of T Tauri disks with photoevaporative disk-wind models
Ch. Rab, M. Weber, T. Grassi +6
Winds in protoplanetary disks play an important role in their evolution and dispersal. However, what physical process is driving the winds is still unclear (i.e. magnetically vs th…
Broadband spectroscopy of astrophysical ice analogues: II. Optical constants of CO and CO ices in the terahertz and infrared ranges
A. A. Gavdush, F. Kruczkiewicz, B. M. Giuliano +7
Context: Broadband optical constants of astrophysical ice analogues in the infrared (IR) and terahertz (THz) ranges are required for modeling the dust continuum emission and radiat…
Optical constants of Ih, Ic, and amorphous HO ices in the THz and IR ranges
A. A. Gavdush, F. Ribeiro, M. K. Matveishina +9
Direct measurements of optical constants in the THz spectral region for astrophysically relevant HO ice samples are scarce. Extrapolation of optical properties in the THz spect…
Carbon Cations and Silicon Atoms in the ISM: modeling their charge exchange reaction
M. Satta, T. Grassi, F. A. Gianturco
The time-dependent rate coefficients for the charge exchange reaction C+ + Si -> C + Si+ for doublet and quartet states have been determined with ab initio quantum calculations cou…
ROBO: a Model and a Code for the Study of the Interstellar Medium
T. Grassi, P. Krstic, E. Merlin +3
We present ROBO, a model and its companion code for the study of the interstellar medium (ISM). The aim is to provide an accurate description of the physical evolution of the ISM a…
Primordial star formation: relative impact of H2 three-body rates and initial conditions
S. Bovino, D. R. G. Schleicher, T. Grassi
Population III stars are the first stars in the Universe to form at z=20-30 out of a pure hydrogen and helium gas in minihalos of 10^5-10^6 M . Cooling and fragmentation is…
Broadband spectroscopy of astrophysical ice analogs. I. Direct measurement of complex refractive index of CO ice using terahertz time-domain spectroscopy
B. M. Giuliano, A. A. Gavdush, B. Müller +9
Context: Reliable, directly measured optical properties of astrophysical ice analogs in the infrared (IR) and terahertz (THz) range are missing. These parameters are of great impor…
Electron attachment rates for PAH anions in the ISM and dark molecular clouds: dependence on their chemical properties
F. Carelli, T. Grassi, F. A. Gianturco
CONTEXT: The attachment of free electrons to polycondensed aromatic ring molecules (PAHs) is studied for the variety of these molecules with different numbers of condensed rings an…
End-to-end differentiable retrieval of molecular spectra using hydrodynamics, chemistry, and radiative transfer
T. Grassi, G. Vermariën, J. E. Pineda +3
We aim to reproduce observed molecular line emission using a pipeline that couples hydrodynamics, chemistry, and radiative transfer, capable of simultaneously optimizing all releva…
Establishing the evolutionary timescales of the massive star formation process through chemistry
G. Sabatini, S. Bovino, A. Giannetti +6
(Abridged) Understanding the details of the formation process of massive (i.e. M<8-10M) stars is a long-standing problem in astrophysics. [...] We present a method to deriv…
Reducing the complexity of chemical networks via interpretable autoencoders
T. Grassi, F. Nauman, J. P. Ramsey +3
In many astrophysical applications, the cost of solving a chemical network represented by a system of ordinary differential equations (ODEs) grows significantly with the size of th…
Impact of cosmic-ray propagation on the chemistry and ionisation fraction of dark clouds
G. Latrille, A. Lupi, S. Bovino +3
A proper modelling of the cosmic-ray ionisation rate within gas clouds is crucial to describe their chemical evolution accurately. However, this modelling is computationally demand…
The formation of the primitive star SDSS J102915+172927: effect of the dust mass and the grain-size distribution
S. Bovino, T. Grassi, D. R. G. Schleicher +1
Understanding the formation of the extremely metal poor star SDSS-J102915+172927 is of fundamental importance to improve our knowledge on the transition between the first and secon…
The challenges of modelling microphysics: ambipolar diffusion, chemistry, and cosmic rays in MHD shocks
T. Grassi, M. Padovani, J. P. Ramsey +4
From molecular clouds to protoplanetary disks, non-ideal magnetic effects are important in many astrophysical environments. Indeed, in star and disk formation processes, it has bec…
A 3D physico-chemical model of a pre-stellar core. II. Dynamic chemical evolution in a pre-stellar core model using tracer particles
S. S. Jensen, S. Spezzano, P. Caselli +3
This work explores the differences between static and dynamically evolving physico-chemical models of pre-stellar cores. A 3D MHD model of a pre-stellar core embedded in a dynamic…
Impact of an accurate modeling of primordial chemistry in high resolution studies
S. Bovino, T. Grassi, M. A. Latif +1
The formation of the first stars in the Universe is regulated by a sensitive interplay of chemistry and cooling with the dynamics of a self-gravitating system. As the outcome of th…
Electron-attachment rates for carbon-rich molecules in protoplanetary atmospheres: the role of chemical differences
F. Carelli, T. Grassi, F. Sebastianelli +1
The formation of anionic species in the interstellar medium from interaction of linear molecules containing carbon, nitrogen and hydrogen as atomic components (polyynes) with free…
Broadband spectroscopy of astrophysical ice analogues: IV. Optical constants of N ice in the terahertz and mid-infrared ranges
F. Kruczkiewicz, A. A. Gavdush, F. Ribeiro +9
Context. Understanding the optical properties of astrophysical ices is crucial for modeling dust continuum emission and radiative transfer in cold, dense interstellar environments.…