A5066906042- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- High-Energy Particle Collisions Research
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Cosmology and Gravitation Theories
- Astrophysical Phenomena and Observations
- Medical Imaging Techniques and Applications
- Geophysics and Gravity Measurements
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Calibration and Measurement Techniques
- Spectroscopy and Laser Applications
- Protein Tyrosine Phosphatases
- Crystal Structures and Properties
- Inorganic Fluorides and Related Compounds
- Scientific Research and Discoveries
- Neutrino Physics Research
- History and Developments in Astronomy
- Metalloenzymes and iron-sulfur proteins
- Adaptive optics and wavefront sensing
Ludwig-Maximilians-Universität München
2015-2019
Excellence Cluster Universe
2016-2019
University of Bonn
2011-2015
Délégation Paris 7
2014
Université Paris Cité
2014
AlbaNova
2009
Stockholm University
2009
Michigan State University
2006-2007
Goethe University Frankfurt
2000-2005
The nearby supernova SN 2011fe can be observed in unprecedented detail. Therefore, it is an important test case for Type Ia (SN Ia) models, which may bring us closer to understanding the physical nature of these objects. Here, we explore how available and expected future observations used constrain explosion scenarios. We base our discussion on three-dimensional simulations a delayed detonation Chandrasekhar-mass white dwarf violent merger two dwarfs-realizations models appropriate most...
We present 32 epochs of optical (3300-9700 \AA) spectrophotometric observations the nearby quintessential "normal" type Ia supernova (SN Ia) SN 2011fe in galaxy M101, extending from -15 to +97 d with respect B-band maximum, obtained by Nearby Supernova Factory collaboration. is closest (\mu = 29.04) and brightest (Bmax 9.94 mag) observed since advent modern large scale programs for intensive periodic followup supernovae. Both synthetic light curve measurements spectral feature analysis...
We examine the relationship between Type Ia supernova (SN Ia) Hubble residuals and properties of their host galaxies using a sample 115 SNe from Nearby Supernova Factory. use galaxy stellar masses specific star formation rates fitted photometry for all hosts, as well gas-phase metallicities subset 69 star-forming (non-active galactic nucleus) to show that SN correlate with each these properties. With data we find new evidence correlation intrinsic color metallicity. When combine our those...
We present a sample of normal Type Ia supernovae (SNe Ia) from the Nearby Supernova Factory data set with spectrophotometry at sufficiently late phases to estimate ejected mass using bolometric light curve. measure 56Ni masses peak luminosity, then compare luminosity in 56Co-decay tail expected rate radioactive energy release ejecta given mass. infer Bayesian context semi-analytic model ejecta, incorporating constraints contemporary numerical models as priors on density structure and...
The Dark Energy Survey (DES) is a five-year optical imaging campaign with the goal of understanding origin cosmic acceleration. DES performs 5000 square degree survey southern sky in five bands (g,r,i,z,Y) to depth ~24th magnitude. Contemporaneously, deep, time-domain four (g,r,i,z) over 27 degrees. exposures are processed nightly an evolving data reduction pipeline and evaluated for image quality determine if they need be retaken. Difference transient source detection also performed time...
A variety of physical phenomena can lead to viscous effects. Several sources shear and bulk viscosity are reviewed with an emphasis on the associated chiral restoration chemical nonequilibrium. We show that in linear response approximation a mean field treatment limiting case second-order phase transition, peaks singularity at critical point.
We employ 76 type Ia supernovae with optical spectrophotometry within 2.5 days of B-band maximum light obtained by the Nearby Supernova Factory to derive impact Si and Ca features on intrinsic luminosity determine a dust reddening law. use equivalent width II {\lambda}4131 in place curve stretch account for first-order variability. The resultant empirical spectral law exhibits strong associated {\lambda}6355. After applying correction based H&K we find consistent Cardelli extinction Using...
We present a new atmospheric extinction curve for Mauna Kea spanning 3200--9700 \AA. It is the most comprehensive to date, being based on some 4285 standard star spectra obtained 478 nights spread over period of 7 years by Nearby SuperNova Factory using Integral Field Spectrograph. This mean and its dispersion can be used as an aid in calibrating spectroscopic or imaging data from Kea, estimating calibration uncertainty associated with use curve. Our method decomposing into physical...
We present optical photometry and spectroscopy of five Type Ia supernovae discovered by the Nearby Supernova Factory selected to be spectroscopic analogs candidate super-Chandrasekhar-mass events SN 2003fg 2007if. Their spectra are characterized hot, highly ionized photospheres near maximum light, for which 1991T supplies best phase coverage among available close spectral templates. Like 2007if, these overluminous (−19.5 < MV −20) velocity Si ii λ6355 absorption minimum is consistent with...
Context. Our Local Group of galaxies appears to be moving relative the cosmic microwave background with source peculiar motion still uncertain. While in past this has been studied mostly using as distance indicators, weight type Ia supernovae (SNe Ia) increased recently continuously improving statistics available low-redshift supernovae. Aims. We measured bulk flow nearby universe ($0.015 < z 0.1$) 117 SNe observed by Nearby Supernova Factory, well Union2 compilation SN data already...
We present convincing evidence of unburned carbon at photospheric velocities in new observations 5 Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified examining 346 spectra from 124 before +2.5 d relative to maximum. Detections based on presence relatively strong C II 6580 absorption "notches" multiple each SN, aided automated fitting with SYNAPPS code. Four question otherwise spectroscopically unremarkable, ions and ejection typical Ia, but fifth...
We present an analysis of anomaly detection for machine learning redshift estimation. Anomaly allows the removal poor training examples, which can adversely influence estimates. Anomalous examples may be photometric galaxies with incorrect spectroscopic redshifts, or one more poorly measured quantity. select 2.5 million 'clean' SDSS DR12 reliable and 6730 'anomalous' measurements are flagged as unreliable. contaminate clean base galaxy sample unreliable redshifts attempt to recover...
Abstract Luminous tracers of large-scale structure are not entirely representative the distribution mass in our Universe. As they arise from highest peaks matter density field, spatial luminous objects is biased towards those peaks. On large scales, where fluctuations mild, this bias simply amounts to a constant offset clustering amplitude tracer, known as linear bias. In work we focus on relative between galaxies and galaxy clusters that located inside vicinity cosmic voids, extended...
We introduce a model for the real-time evolution of relativistic fluid quarks coupled to non-equilibrium dynamics long wavelength (classical) modes chiral condensate. solve equations motion numerically in 3+1 space-time dimensions. Starting at high temperature symmetric phase, we study dynamical trajectories that either cross line first-order phase transitions or evolve through its critical endpoint. For those cases, predict behavior azimuthal momentum asymmetry high-energy heavy-ion...
We describe the model for mapping from sky brightness to digital output of Dark Energy Camera (DECam) and algorithms adopted by Survey (DES) inverting this obtain photometric measures celestial objects raw camera output. This calibration aims fluxes that are uniform across field view full angular temporal span DES observations, approaching accuracy limits set shot noise dynamic range observations. The pipeline incorporates several substantive advances over standard detrending techniques,...
We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory (SNfactory). Combining GALEX UV data with optical near infrared photometry, we employ stellar population synthesis techniques to measure SN host galaxy masses, star-formation rates (SFRs), reddening due dust. reinforce key role in deriving accurate estimates SFRs dust extinction. Optical spectra are fitted simultaneously for their continua emission...
We present a ground-based near-infrared search for lensed supernovae behind the massive cluster Abell 1689 at z=0.18, one of most powerful gravitational telescopes that nature provides. Our survey was based on multi-epoch $J$-band observations with HAWK-I instrument VLT, supporting optical data from Nordic Optical Telescope. resulted in discovery five high-redshift, $0.671<z<1.703$, photometrically classified core-collapse magnifications range $\Delta m$ = $-0.31$ to $-1.58$ mag, as...
We present a novel class of models for Type Ia supernova time-evolving spectral energy distributions (SEDs) and absolute magnitudes: they are each modeled as stochastic functions described by Gaussian processes. The values the SED magnitudes defined through well-defined regression prescriptions, so that data directly inform models. As proof concept, we implement model synthetic photometry built from spectrophotometric time series Nearby Supernova Factory. Absolute at peak B brightness...
We report results of a study Planck Sunyaev-Zel'dovich effect (SZE) selected galaxy cluster candidates using the Panoramic Survey Telescope & Rapid Response System (Pan-STARRS) imaging data. first examine 150 confirmed clusters with spectroscopic redshifts to test our algorithm for identifying optical counterparts and measuring their redshifts; have typical accuracy $\sigma_{z/(1+z)} \sim 0.022$ this sample. Using 60 random sky locations, we estimate that chance contamination through...
Powerful gravitational telescopes in the form of massive galaxy clusters can be used to enhance light collecting power over a limited field view by about an order magnitude flux. This effect is exploited here increase depth survey for lensed supernovae at near-IR wavelengths. A pilot SN search program conducted with ISAAC camera VLT presented. Lensed galaxies behind A1689, A1835 and AC114 were observed total 20 hours split into 2, 3 4 epochs respectively, separated approximately one month...
We present Keck LRIS spectroscopy and $g$-band photometry of the metal-poor, low-luminosity host galaxy super-Chandrasekhar mass Type Ia supernova SN 2007if. Deep imaging reveals its apparent magnitude to be $m_g=23.15\pm0.06$, which at spectroscopically-measured redshift $z_{helio}=0.07450\pm0.00015$ corresponds an absolute $M_g=-14.45\pm0.06$. Galaxy $g-r$ color constrains mass-to-light ratio, giving a stellar estimate $\log(M_*/M_\odot)=7.32\pm0.17$. Balmer absorption in continuum, along...
Our ability to study the most remote supernova explosions, crucial for understanding of evolution high-redshift universe and its expansion rate, is limited by light collection capabilities telescopes. However, nature offers unique opportunities look beyond range within reach our unaided instruments thanks light-focusing power massive galaxy clusters. Here we report on discovery one distant supernovae ever found, at redshift z = 1.703. Due a lensing magnification factor 4.3 ± 0.3, are able...
We present measurements of angular cross power spectra between galaxies and optically-selected galaxy clusters in the final photometric sample Sloan Digital Sky Survey (SDSS). measure auto- cross-correlations cluster samples, from which we extract effective biases study shot noise properties. model non-Poissonian by introducing an number density tracers fit for this quantity. find that can only describe cross-correlation clusters, as well auto-correlation on relevant scales using a...