Results for "Micol Benetti"

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Primordial Non-Gaussianities of inflationary step-like modelsJul 07 2015Oct 02 2015We use Minkowski Functionals to explore the presence of non-Gaussian signatures in simulated cosmic microwave background (CMB) maps. Precisely, we analyse the non-Gaussianities produced from the angular power spectra emerging from a class of inflationary ... More
Swampland conjecture in $f(R)$ gravity by the Noether Symmetry ApproachMay 14 2019Swampland conjecture has been recently proposed to connect early time cosmological models with the string landscape, and then to understand if related scalar fields and potentials can come from some fundamental theory in the high energy regime. In this ... More
Warm inflation dissipative effects: predictions and constraints from the Planck dataOct 27 2016We explore the warm inflation scenario theoretical predictions looking at two different dissipative regimes for several representative primordial potentials. As it is well known, the warm inflation is able to decrease the tensor-to-scalar ratio value, ... More
Bayesian analysis of inflationary features in Planck and SDSS dataApr 27 2016Jul 13 2016We perform a Bayesian analysis to study possible features in the primordial inflationary power spectrum of scalar perturbations. In particular, we analyse the possibility of detecting the imprint of these primordial features in the anisotropy temperature ... More
Testing non-minimally coupled inflation with CMB data: a Bayesian analysisMay 24 2017Jul 20 2017We use the most recent cosmic microwave background (CMB) data to perform a Bayesian statistical analysis and discuss the observational viability of inflationary models with a non-minimal coupling,~$\xi$, between the inflaton field and the Ricci scalar. ... More
Constraining quantum collapse inflationary models with CMB dataOct 10 2016Dec 05 2016The hypothesis of the self-induced collapse of the inflaton wave function was proposed as responsible for the emergence of inhomogeneity and anisotropy at all scales. This proposal was studied within an almost de Sitter space-time approximation for the ... More
Featuring the primordial power spectrum: new constraints on interrupted slow-roll from CMB and LRG dataOct 12 2012Using the most recent data from the WMAP, ACT and SPT experiments, we update the constraints on models with oscillatory features in the primordial power spectrum of scalar perturbations. This kind of features can appear in models of inflation where slow-roll ... More
Constraining quantum collapse inflationary models with CMB dataOct 10 2016The hypothesis of the self-induced collapse of the inflaton wave function was proposed as responsible for the emergence of inhomogeneity and anisotropy at all scales. This proposal was studied within an almost de Sitter space-time approximation for the ... More
A Bayesian analysis of inflationary primordial spectrum models using Planck dataOct 04 2017The current available CMB data show an anomalously low value of the CMB temperature fluctuations at large angular scales (l < 40). This lack of power is not explained by the minimal LCDM model, and one of the possible mechanisms explored in the literature ... More
The $H_0$ and $σ_8$ tensions and the scale invariant spectrumDec 02 2017Jun 21 2018In a previous communication we showed that a joint analysis of Cosmic Microwave Background (CMB) data and the current measurement of the local expansion rate favours a model with a scale invariant spectrum (HZ) over the minimal $\Lambda$CDM scenario provided ... More
Do joint CMB and HST data support a scale invariant spectrum?Feb 21 2017We combine current measurements of the local expansion rate, $H_0$, and Big Bang Nucleosynthesis (BBN) estimates of helium abundance with the latest cosmic microwave background (CMB) data from the Planck Collaboration to discuss the observational viability ... More
Primordial gravitational waves and the H0-tension problemSep 12 2018Feb 16 2019We analyse the H0-tension problem in the context of models of the early universe that predict a blue tilted spectrum of primordial gravitational waves (GW's). By considering the GW's contribution, Neff^GW, to the effective number of relativistic degrees ... More
Features in the primordial spectrum: new constraints from WMAP7+ACT data and prospects for PlanckJul 25 2011Nov 16 2011We update the constraints on possible features in the primordial inflationary density perturbation spectrum by using the latest data from the WMAP7 and ACT Cosmic Microwave Background experiments. The inclusion of new data significantly improves the constraints ... More
Error estimate for a homogenization problem involving the Laplace-Beltrami operatorMay 11 2017Feb 20 2018In this paper we prove a concentration result and an error estimate for a model of heat conduction in composite materials having a microscopic structure arranged in a perodic array and thermally active membranes separating the heat conductive phases.
Phase transitions of regular Schwarzschild-Anti-deSitter black holesFeb 04 2015We study a solution of the Einstein's equations generated by a self-gravitating, anisotropic, static, non-singular matter fluid. The resulting Schwarzschild like solution is regular and accounts for smearing effects of noncommutative fluctuations of the ... More
Constraining quantum collapse inflationary models with current data: The semiclassical approachSep 19 2017Feb 20 2019The hypothesis of the self-induced collapse of the inflaton wave function was introduced as a candidate for the physical process responsible for the emergence of inhomogeneity and anisotropy at all scales. In particular, we consider different proposal ... More
Measuring baryon acoustic oscillations with angular two-point correlation functionNov 25 2016The Baryon Acoustic Oscillations (BAO) imprinted a characteristic correlation length in the large-scale structure of the universe that can be used as a standard ruler for mapping out the cosmic expansion history. Here, we discuss the application of the ... More
Observational constraints on Gauss-Bonnet cosmologyMar 02 2018We analyze a fully geometric approach to dark energy in the framework of $F(R,{\cal G})$ theories of gravity, where $R$ is the Ricci curvature scalar and ${\cal G}$ is the Gauss-Bonnet topological invariant. The latter invariant naturally exhausts, together ... More
Photometric Redshifts based on standard SED fitting proceduresMar 24 2000Oct 04 2000In this paper we study the accuracy of photometric redshifts computed through a standard SED fitting procedure, where SEDs are obtained from broad-band photometry. We present our public code hyperz, which is presently available on the web. We introduce ... More
Asymptotic decay under nonlinear and noncoercive dissipative effects for electrical conduction in biological tissuesJul 22 2015We consider a nonlinear model for electrical conduction in biological tissues. The nonlinearity appears in the interface condition prescribed on the cell membrane. The purpose of this paper is proving asymptotic convergence for large times to a periodic ... More
Luminosity Functions beyond the spectroscopic limit. I. Method and near-infrared LFs in the HDF-N and HDF-SJul 23 2002Aug 27 2002We have developed a Monte Carlo method to compute the luminosity function of galaxies, based on photometric redshifts, which takes into account the non-gaussianity of the probability functions, and the presence of degenerate solutions in redshift. In ... More
Dynamical analysis on $f(R,\mathcal{G})$ cosmologyFeb 07 2018We use a dynamical system approach to study the cosmological viability of $f(R,\mathcal{G})$ gravity theories. The method consists of formulating the evolution equations as an autonomous system of ODEs, using suitable variables. The formalism is applied ... More
Cosmological data and indications for new physicsMar 18 2013Data from the Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT), combined with the nine-year data release from the WMAP satellite, provide very precise measurements of the cosmic microwave background (CMB) angular anisotropies down ... More
FETI-DP for the three-dimensional Virtual Element MethodDec 03 2018We deal with the Finite Element Tearing and Interconnecting Dual Primal (FETI-DP) preconditioner for elliptic problems discretized by the virtual element method (VEM). We extend the result of [16] to the three dimensional case. We prove polylogarithmic ... More
BDDC and FETI-DP for the Virtual Element MethodAug 11 2017Nov 08 2017We build and analyze Balancing Domain Decomposition by Constraint (BDDC) and Finite Element Tearing and Interconnecting Dual Primal (FETI-DP) preconditioners for elliptic problems discretized by the virtual element method (VEM). We prove polylogarithmic ... More
On the Finsler metrics obtained as limits of chessboard structuresApr 28 2008We study the geodesics in a planar chessboard structure with two values 1 and $\beta>1$. The results for a fixed structure allow us to infer the properties of the Finsler metrics obtained, with an homogenization procedure, as limit of oscillating chessboard ... More
Induced Hausdorff metrics on quotient spacesApr 25 2016Sep 27 2016Let $G$ be a group, $(M,d)$ be a metric space, $X$ be a compact subspace of $M$ and $\varphi:G\times M \rightarrow M$ be a left action by homeomorphisms of $G$ on $M$. Denote $gp=f(g,p)$. The isotropy subgroup of $G$ with respect to $X$ is defined by ... More
Accuracy of photometric redshifts for future weak lensing surveys from spaceJan 17 2012Mar 21 2012Photometric redshifts are a key tool to extract as much information as possible from planned cosmic shear experiments. In this work we aim to test the performances that can be achieved with observations in the near-infrared from space and in the optical ... More
Cluster galaxies: contribution to the arc statisticsAug 30 2000We present the results of a set of numerical simulations aiming at evaluating the effects of cluster galaxies on the arc statistics. At this goal we use nine different galaxy clusters obtained from N-body simulations. We mimic the presence of a population ... More
Star Formation History of a Young Super-Star Cluster in NGC 4038/39: Direct Detection of Low Mass Pre-Main Sequence StarsJan 12 2010We present an analysis of the near-infrared spectrum of a young massive star cluster in the overlap region of the interacting galaxies NGC 4038/39 using population synthesis models. Our goal is to model the cluster population as well as provide rough ... More
Effects of cluster galaxies on arc statisticsJul 23 1999Jan 11 2000We present the results of a set of numerical simulations evaluating the effect of cluster galaxies on arc statistics. We perform a first set of gravitational lensing simulations using three independent projections for each of nine different galaxy clusters ... More
Photometric Redshifts in lensing clusters: Identification and Calibration of faint high-z galaxiesJul 05 1999We discuss a method aiming to use photometric redshifts in lensing clusters to access the population of distant background sources. The amplification provided by gravitational lensing allows to calibrate photometric redshifts 1 to 3 magnitudes deeper ... More
FETI-DP preconditioners for the Virtual Element Method on general 2D meshesApr 26 2018We analyze the performance of a state-of-the-art domain decomposition approach, the Finite Element Tearing and Interconnecting Dual Primal (FETI-DP) method, for the efficient solution of very large linear systems arising from elliptic problems discretized ... More
Preparing a public database of radio sourcesJul 22 1996We have collected the largest existing set of radio source lists in machine-readable form: 320 tables with 1.75 million records. Only a minor fraction of these is accessible via public databases. We describe our plans to make this huge amount of heterogeneous ... More
Supernova Classes and SubclassesJun 08 2007The discovery of many objects with unprecedented, amazing observational characteristics caused the last decade to be the most prolific period for the supernova research. Many of these new supernovae are transitional objects between existing classes, others ... More
Exploring the spectroscopic diversity of Type Ia SupernovaeApr 21 2006Jul 06 2006The velocities and equivalent widths (EWs) of a set of absorption features are measured for a sample of 28 well-observed Type Ia supernovae (SN Ia) covering a wide range of properties. The values of these quantities at maximum are obtained through interpolation/extrapolation ... More
Collisional relaxation in the inhomogeneous Hamiltonian-Mean-Field model: diffusion coefficientsOct 21 2016Systems of particles with long range interactions present two important processes: first, the formation of out-of-equilibrium quasi-stationary states (QSS), and the collisional relaxation towards Maxwell-Boltzmann equilibrium in a much longer timescale. ... More
Gravitational free energy in topological AdS/CFTApr 23 2018Sep 20 2018We define and study a holographic dual to the topological twist of $\mathcal{N}=4$ gauge theories on Riemannian three-manifolds. The gravity duals are solutions to four-dimensional $\mathcal{N}=4$ gauged supergravity, where the three-manifold arises as ... More
Collisional relaxation in the inhomogeneous Hamiltonian-Mean-Field model: diffusion coefficientsOct 21 2016Feb 06 2017Systems of particles with long range interactions present two important processes: first, the formation of out-of-equilibrium quasi-stationary states (QSS), and the collisional relaxation towards Maxwell-Boltzmann equilibrium in a much longer timescale. ... More
Variety in SupernovaeNov 11 2002Detailed observations of a growing number of supernovae have determined a bloom of new peculiar events. In this paper we take a short tour through the SN diversity and discuss some important, physical issues related to it. Because of the role of SN Ia ... More
Topological AdS/CFTJul 26 2017Apr 25 2018We define a holographic dual to the Donaldson-Witten topological twist of $\mathcal{N}=2$ gauge theories on a Riemannian four-manifold. This is described by a class of asymptotically locally hyperbolic solutions to $\mathcal{N}=4$ gauged supergravity ... More
Hybrid Subspace Learning for High-Dimensional DataAug 05 2018The high-dimensional data setting, in which p >> n, is a challenging statistical paradigm that appears in many real-world problems. In this setting, learning a compact, low-dimensional representation of the data can substantially help distinguish signal ... More
A Population of Compact Elliptical Galaxies Detected with the Virtual ObservatoryOct 01 2009Compact elliptical galaxies are characterized by small sizes and high stellar densities. They are thought to form through tidal stripping of massive progenitors. However, only a handful of them were known, preventing us from understanding the role played ... More
IVOA Recommendation: Data Model for Astronomical DataSet CharacterisationNov 09 2011This document defines the high level metadata necessary to describe the physical parameter space of observed or simulated astronomical data sets, such as 2D-images, data cubes, X-ray event lists, IFU data, etc.. The Characterisation data model is an abstraction ... More
Nonequilibrium phase transitions in systems with long-range interactionsNov 07 2012Apr 10 2013We introduce a generalized Hamiltonian Mean Field Model (gHMF)-XY model with both linear and quadratic coupling between spins and explicit Hamiltonian dynamics. In addition to the usual paramagnetic and ferromagnetic phases, this model also possesses ... More
Abundance stratification in Type Ia supernovae - I. The case of SN 2002boSep 14 2004Aug 12 2005The abundance stratification in the ejecta of the normal Type Ia supernova 2002bo is derived by fitting a series of spectra obtained at close time intervals. A Monte Carlo code, modified to include abundance stratification, is used to compute synthetic ... More
The 3-D ionization structure and evolution of NGC 7009 (Saturn Nebula)Dec 10 2003Tomographic and 3-D analyses for extended, emission-line objects are applied to long-slit ESO NTT + EMMI high-resolution spectra of the intriguing planetary nebula NGC 7009, covered at twelve position angles. We derive the gas expansion law, the diagnostics ... More
The tetra-lobed planetary nebula NGC 1501Jul 04 2000Direct imagery and long-slit, spatially resolved echellograms of the high excitation planetary nebula NGC 1501 allowed us to study in detail the expansion velocity field, the physical conditions (electron temperature, electron density, ionization) and ... More
3-D ionization structure (in stereoscopic view) of Planetary Nebulae: the case of NGC 1501Feb 21 2001Long-slit echellograms of the high excitation planetary nebula NGC1501, reduced according to the methodology developed by Sabbadin et al. (2000a, b), allowed us to obtain the ``true'' distribution of the ionized gas in the eight nebular slices covered ... More
The gas turbulence in planetary nebulae: quantification and multi-D maps from long-slit, wide-spectral range echellogramJun 30 2008This methodological paper is part of a short series dedicated to the long-standing astronomical problem of de-projecting the bi-dimensional, apparent morphology of a three-dimensional distribution of gas. We focus on the quantification and spatial recovery ... More
The holographic supersymmetric Casimir energyJun 08 2016We consider a general class of asymptotically locally AdS_5 solutions of minimal gauged supergravity, that are dual to superconformal field theories on curved backgrounds S^1 x M_3 preserving two supercharges. We demonstrate that standard holographic ... More
The 3--D ionization structure of NGC 6818: a Planetary Nebula threatened by recombinationNov 21 2002Long-slit NTT+EMMI echellograms of NGC 6818 (the Little Gem) at nine equally spaced position angles, reduced according to the 3-D methodology introduced by Sabbadin et al. (2000a,b), allowed us to derive: the expansion law, the diagnostics and ionic radial ... More
The 3-D ionization structure of the planetary nebula NGC6565Jan 24 2002A detailed study of the planetary nebula NGC6565 has been carried out on long-slit echellograms at six, equally spaced position angles. The expansion velocity field, the c(Hbeta) distribution and the radial profile of the physical conditions (electron ... More
Spectroscopic and Photometric Observations of SN IIn 1995NApr 05 2005We present the results of a long-term program of monitoring of the famous SN 1995N, observed both in photometry (UBVRIJHK bands) and optical spectroscopy. The observations span a period of about 9 years. These new data, together with others available ... More
Holographic renormalization and supersymmetryDec 20 2016Jan 16 2017Holographic renormalization is a systematic procedure for regulating divergences in observables in asymptotically locally AdS spacetimes. For dual boundary field theories which are supersymmetric it is natural to ask whether this defines a supersymmetric ... More
A Common Explosion Mechanism for Type Ia SupernovaeFeb 13 2007Type Ia supernovae, the thermonuclear explosions of white dwarf stars composed of carbon and oxygen, were instrumental as distance indicators in establishing the acceleration of the universe's expansion. However, the physics of the explosion are debated. ... More
Mean-field model for the density of states of jammed soft spheresApr 08 2018Jun 29 2018We propose a class of mean-field models for the isostatic transition of systems of soft spheres, in which the contact network is modeled as a random graph and each contact is associated to $d$ degrees of freedom. We study such models in the hypostatic, ... More
The Hubble Legacy Archive NICMOS Grism DataSep 15 2008The Hubble Legacy Archive (HLA) aims to create calibrated science data from the Hubble Space Telescope archive and make them accessible via user-friendly and Virtual Observatory (VO) compatible interfaces. It is a collaboration between the Space Telescope ... More
Reflections on Reflexions: II. Effects of Light Echoes on the luminosity and spectra of Type Ia SupernovaeDec 22 2005In this paper we present and discuss the effects of scattered light echoes (LE) on the luminosity and spectral appearance of Type Ia Supernovae (SNe). After introducing the basic concepts of LE spectral synthesis, by means of LE models and real observations ... More
Tomography of the low excitation planetary nebula NGC 40Dec 02 1999Spatially resolved, long-slit echellograms at different position angles of the bright, low excitation planetary nebula NGC 40 indicate that, the higher is the gas excitation, the faster is the radial motion, thus confirming the overturn of the Wilson ... More
The structure of Planetary Nebulae: theory vs. practiceJan 13 2006This paper - the first of a short series dedicated to the long-stan ding astronomical problem of de-projecting the bi-dimensional apparent morpholog y of a three-dimensional mass of gas - focuses on the density distribution in real Planetary Nebulae (and ... More
The 3-D shaping of NGC 6741: a massive, fast-evolving Planetary Nebula at the recombination--reionization edgeFeb 04 2005We infer the gas kinematics, diagnostics and ionic radial profiles, distance and central star parameters, nebular photo- ionization model, spatial structure and evolutionary phase of the PN NGC 6741 by means of long-slit high-resolution spectra at nine ... More
The holographic supersymmetric Casimir energyJun 08 2016Dec 30 2016We consider a general class of asymptotically locally AdS_5 solutions of minimal gauged supergravity, that are dual to superconformal field theories on curved backgrounds S^1 x M_3 preserving two supercharges. We demonstrate that standard holographic ... More
The Disappearance of the Red Supergiant Progenitor of Supernova 2008bkNov 24 2010Oct 08 2013Massive stars end their lives in spectacular supernova explosions. Identifying the progenitor star is a test of stellar evolution and explosion models. Here we show that the progenitor star of the supernova SN 2008bk has now disappeared, which provides ... More
Consistent estimates of (56)Ni yields for type Ia supernovaeSep 08 2006Sep 17 2006We present (56)Ni mass estimates for seventeen well-observed type Ia supernovae determined by two independent methods. Estimates of the (56)Ni mass for each type Ia supernova are determined from (1) modeling of the late-time nebular spectrum and (2) through ... More
Recent results and perspectives on cosmology and fundamental physics from microwave surveysApr 13 2016Recent cosmic microwave background data in temperature and polarization have reached high precision in estimating all the parameters that describe the current so-called standard cosmological model. Recent results about the integrated Sachs-Wolfe effect ... More
The Hubble Legacy Archive ACS Grism DataMar 24 2011A public release of slitless spectra, obtained with ACS/WFC and the G800L grism, is presented. Spectra were automatically extracted in a uniform way from 153 archival fields (or "associations") distributed across the two Galactic caps, covering all observations ... More
IVOA Recommendation: Observation Data Model Core Components and its Implementation in the Table Access Protocol Version 1.0Nov 07 2011Nov 14 2011This document defines the core components of the Observation data model that are necessary to perform data discovery when querying data centers for observations of interest. It exposes use-cases to be carried out, explains the model and provides guidelines ... More
High order VEM on curved domainsNov 12 2018We deal with the virtual element method (VEM) for solving the Poisson equation on a domain $\Omega$ with curved boundaries. Given a polygonal approximation $\Omega_h$ of the domain $\Omega$, the standard order $m$ VEM [6], for $m$ increasing, leads to ... More
Nonlinear characterisation of a silicon integrated Bragg waveguide filterFeb 15 2018Bragg waveguides are promising optical filters for pump suppression in spontaneous Four-Wave Mixing (FWM) photon sources. In this work, we investigate the generation of unwanted photon pairs in the filter itself. We do this by taking advantage of the ... More
The Rate of Supernovae. II. the Selection Effects and the Frequencies Per Unit Blue LuminosityFeb 25 1993We present new estimates of the observed rates of SNe determined with the {\em control time} method applied to the files of observations of two long term, photographic SN searches carried out at the Asiago and Sternberg Observatories. Our calculations ... More
Simultaneous XMM-Newton and ESO VLT observations of SN 1995N: probing the wind/ejecta interactionOct 03 2005We present the results of the first {\it XMM-Newton} observation of the interacting type IIn supernova 1995N, performed in July 2003. We find that the 0.2--10.0 keV unabsorbed flux dropped at a value of $\simeq 1.8 \times 10^{-13}$ erg cm$^{-2}$ s$^{-1}$, ... More
Mass limits for the progenitor star of supernova 2001du and other type II-P supernovaeJan 16 2003Apr 29 2003The supernova SN2001du in the galaxy NGC1365 (19+/-2Mpc), is a core-collapse event of type II-P. Images of this galaxy, have been taken with HST approximately 6.6 years before discovery and include the supernova position on the WFPC2 field of view. We ... More
Ergodicity Breaking and Parametric Resonances in Systems with Long-Range InteractionsFeb 08 2012Feb 10 2012We explore the mechanism responsible for the ergodicity breaking in systems with long-range forces. In thermodynamic limit such systems do not evolve to the Boltzmann-Gibbs equilibrium, but become trapped in an out-of-equilibrium quasi-stationary-state. ... More
VLT Spectropolarimetry of the optical transient in NGC300. Evidence for asymmetry in the circumstellar dustAug 07 2009Dec 18 2009AIMS: The main goal of this work is to study possible signs of asymmetry in the bright optical transient in NGC300, with the aim of getting independent information on the explosion mechanism, the progenitor star and its circumstellar environment. METHODS: ... More
Nebular velocities in type Ia Supernovae and their relationship to light curvesMar 19 1998Recently gathered observational data on a sample of Type Ia Supernovae (SNe Ia) reveal a wide distribution of expansion velocities of the Fe cores, measured from the width of the nebular lines. Moreover, the velocity appears to correlate with the luminosity ... More
Supersymmetric gauge theories on five-manifoldsMar 31 2015Aug 24 2015We construct rigid supersymmetric gauge theories on Riemannian five-manifolds. We follow a holographic approach, realizing the manifold as the conformal boundary of a six-dimensional bulk supergravity solution. This leads to a systematic classification ... More
Nonequilibrium stationary states of 3D self-gravitating systemsSep 06 2014Three dimensional self-gravitating systems do not evolve to thermodynamic equilibrium, but become trapped in nonequilibrium quasistationary states. In this Letter we present a theory which allows us to a priori predict the particle distribution in a final ... More
Photoacoustic Sensing of Trapped Fluids in Nanoporous Thin Films: Device Engineering and Sensing SchemeAug 14 2018Accessing fluid infiltration in nanogranular coatings is an outstanding challenge, of relevance for applications ranging from nanomedicine to catalysis. A sensing platform, allowing to quantify the amount of fluid infiltrated in a nanogranular ultrathin ... More
Refined 3d-3d CorrespondenceFeb 16 2017Mar 08 2017We explore aspects of the correspondence between Seifert 3-manifolds and 3d $\mathcal{N}=2$ supersymmetric theories with a distinguished abelian flavour symmetry. We give a prescription for computing the squashed three-sphere partition functions of such ... More
IVOA Recommendation: Simple Spectral Access Protocol Version 1.1Mar 26 2012The Simple Spectral Access (SSA) Protocol (SSAP) defines a uniform interface to remotely discover and access one dimensional spectra. SSA is a member of an integrated family of data access interfaces altogether comprising the Data Access Layer (DAL) of ... More
Peculiar, Low Luminosity Type II Supernovae: Low Energy Explosions in Massive Progenitors?Oct 08 2002A number of supernovae, classified as Type II, show remarkably peculiar properties such as an extremely low expansion velocity and an extraordinarily small amount of $^{56}$Ni in the ejecta. We present a joint analysis of the available observations for ... More
SN 1995ah-the first supernova observed in a Blue Compact Dwarf galaxyJul 28 1997We present the properties of the supernova SN 1995ah discovered in a Blue Compact Dwarf galaxy (BCD) around 10 days after the maximum. This is the first supernova event observed in a BCD. The photometric and spectroscopic data suggest that SN 1995ah is ... More
Supernova 1996L: evidence of a strong wind episode before the explosionJan 25 1999Observations of the type II SN 1996L reveal the presence of a slowly expanding (V~700$ km/s) shell at ~ 10^(16) cm from the exploding star. Narrow emission features are visible in the early spectra superposed on the normal SN spectrum. Within about two ... More
Nonequilibrium Statistical Mechanics of Systems with Long-Range Interactions: Ubiquity of Core-Halo DistributionsOct 03 2013Systems with long-range (LR) forces, for which the interaction potential decays with the interparticle distance with an exponent smaller than the dimensionality of the embedding space, remain an outstanding challenge to statistical physics. The internal ... More
Measuring the transverse baryonic acoustic scale from the SDSS DR11 galaxiesSep 01 2017We report five measurements of the transverse baryonic acoustic scale, $\theta_{BAO}$, obtained from the angular two-point correlation function calculation for Luminous Red Galaxies of the eleventh data release of the Sloan Digital Sky Survey (SDSS). ... More
Spectral luminosity indicators in SNe Ia - Understanding the R(SiII) line strength ratio and beyondJun 25 2008SNe Ia are good distance indicators because the shape of their light curves, which can be measured independently of distance, varies smoothly with luminosity. This suggests that SNe Ia are a single family of events. Similar correlations are observed between ... More
Supernova 1994aj: a probe for pre-supernova evolution and mass loss from the progenitorJun 18 1997Extensive photometric and spectroscopic observations of SN1994aj until 540d after maximum light have been obtained. The photometry around maximum suggests that the SN belongs to the Type II Linear class, with a peak absolute magnitude of Mv ~ -17.8 (assuming ... More
Abundance stratification in Type Ia Supernovae - II: The rapidly declining, spectroscopically normal SN 2004eoMar 10 2008The variation of properties of Type Ia supernovae, the thermonuclear explosions of Chandrasekhar-mass carbon-oxygen white dwarfs, is caused by different nucleosynthetic outcomes of these explosions, which can be traced from the distribution of abundances ... More
Supernova 2002ic: the collapse of a stripped-envelope, massive star in a dense medium ?Nov 03 2006We revisit the case of SN2002ic that recently revived the debate about the progenitors of SNeIa after the claim of the unprecedented presence of hydrogen lines over a diluted SNIa spectrum. As an alternative to the previous interpretation, we suggest ... More
A new faint Type Ia Supernova: SN 1997cn in NGC 5490Aug 03 1998Observations of the recent SN 1991bg in the elliptical galaxy NGC 5490 show that this objects closely resembles, both photometrically and spectroscopically, the faint SNIa 1991bg. The two objects have similar light curves, which do not show secondary ... More
Abundance stratification in Type Ia Supernovae - IV: the luminous, peculiar SN 1991TAug 30 2014The abundance distribution of the elements in the ejecta of the peculiar, luminous Type Ia supernova (SN Ia) 1991T is obtained modelling spectra from before maximum light until a year after the explosion, with the method of "Abundance Tomography". SN ... More
The nebular spectrum of the type Ia supernova 2003hv: evidence for a non-standard eventMay 06 2011The optical and near-infrared late-time spectrum of the under-luminous Type Ia supernova 2003hv is analysed with a code that computes nebular emission from a supernova nebula. Synthetic spectra based on the classical explosion model W7 are unable to reproduce ... More
A new photopolymer based VPHG for astronomy: The case of SN 2013fjJan 31 2014The spectroscopic studies of near infrared emission arising from supernovae allow to derive crucial quantities that could better characterise physical conditions of the expanding gas, such as the CaII IR HVF spectral feature. For this reason is mandatory ... More
Cosmic shear from STIS Pure Parallels: I DataFeb 20 2001Jun 15 2001Following the second HST servicing mission in 1997 when the STIS instrument was installed and the capability for parallel observations was enhanced, a substantial archive of non-proprietary parallel data has been accumulating. In this paper, we discuss ... More
Exceptionally Bright Type Ib Supernova 1991DMay 27 2002Photometric and spectroscopic observations of the peculiar Type Ib Supernova 1991D are presented. SN 1991D was exceptionally bright for a Type Ib supernova. The He I lines were rather weak and the velocity at the photosphere as a function of time was ... More
Polarimetric evolution of V838 MonOct 03 2003We present the results of our polarimetric and spectropolarimetric monitoring of V838 Monocerotis, performed at Asiago and Crimean observatories during and after the multiple outbursts that occurred in January-March 2002. The polarization of the object ... More
Constraining the physical properties of Type II-P supernovae using nebular phase spectraNov 30 2011We present a study of the nebular phase spectra of a sample of Type II-Plateau supernovae with identified progenitors or restrictive limits. The evolution of line fluxes, shapes, and velocities are compared within the sample, and interpreted by the use ... More
GMASS ultradeep spectroscopy of galaxies at z~2 - VII. Sample selection and spectroscopySep 07 2012The populations of both quiescent and actively star-forming galaxies at 1<z<2 are still under-represented in our spectroscopic census of galaxies throughout the history of the Universe. In the light of galaxy formation models, however, the evolution of ... More
Detection of a light echo from SN1998buJan 19 2001About 500d after explosion the light curve of the Type Ia SN1998bu suddenly flattened and at the same time the spectrum changed from the typical nebular emission to a blue continuum with broad absorption and emission features reminiscent of the SN spectrum ... More