A. Hornstrup
A5050667784- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Radio Astronomy Observations and Technology
- Scientific Research and Discoveries
- Adaptive optics and wavefront sensing
- Calibration and Measurement Techniques
- Pulsars and Gravitational Waves Research
- Solar and Space Plasma Dynamics
- Particle Detector Development and Performance
- X-ray Spectroscopy and Fluorescence Analysis
- Geophysics and Gravity Measurements
- Astro and Planetary Science
- Statistical and numerical algorithms
- History and Developments in Astronomy
- Advanced X-ray Imaging Techniques
- Atmospheric Ozone and Climate
- Remote Sensing in Agriculture
Technical University of Denmark
2014-2025
University College London
2024
University of Copenhagen
2024
Flatiron Health (United States)
2024
Flatiron Institute
2024
Royal Holloway University of London
2024
University of California, Davis
2024
New York University
2024
Princeton University
2024
DAWN Center for Independent Living
2023-2024
The Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched on 2012 June 13, is the first focusing high-energy X-ray telescope in orbit. NuSTAR operates band from 3 to 79 keV, extending sensitivity of far beyond ∼10 keV cutoff achieved by all previous satellites. inherently low background associated with concentrating light enables probe hard sky a more than 100-fold improvement over collimated or coded mask instruments that have operated this bandpass. Using its unprecedented...
We present the implications for cosmic inflation of Planck measurements microwave background (CMB) anisotropies in both temperature and polarization based on full survey, which includes more than twice integration time nominal survey used 2013 release papers. The mission data a first large angular scales measure spectral index curvature perturbations to be ns = 0.968 ± 0.006 tightly constrain its scale dependence dns/ dlnk −0.003 0.007 when combined with lensing likelihood. When high-ℓ are...
We analyse the implications of Planck data for cosmic inflation. The nominal mission temperature anisotropy measurements, combined with WMAP large-angle polarization, constrain scalar spectral index to $n_s = 0.9603 \pm 0.0073$, ruling out exact scale invariance at over 5 $\sigma$. establishes an upper bound on tensor-to-scalar ratio r < 0.11 (95% CL). thus shrink space allowed standard inflationary models, preferring potentials V" 0. Exponential potential simplest hybrid and monomial models...
This paper characterizes the effective beams,the beam window functions and associated errors for Planck HFI detectors. The is angular response including effect of optics,detectors,data processing scan strategy. function representation this in harmonic domain which required to recover an unbiased measurement CMB power spectrum. a scanning instrument its beams are convolution of: (a) optical telescope feeds;(b)the time-ordered data deconvolution bolometric electronic time response; (c) merging...
Chandra observations of large samples galaxy clusters detected in X-rays by ROSAT provide a new, robust determination the cluster mass functions at low and high redshifts. Statistical systematic errors are now sufficiently small, redshift leverage for function evolution to be used as useful growth structure-based dark energy probe. In this paper, we present cosmological parameter constraints obtained from 37 with 〈z〉 = 0.55 derived 400 deg2 serendipitous survey 49 brightest z ≈ 0.05 All-Sky...
This paper presents the Planck 2015 likelihoods, statistical descriptions of 2-point correlations CMB data, using hybrid approach employed previously: pixel-based at $\ell<30$ and a Gaussian approximation to distribution spectra higher $\ell$. The main improvements are use more better processed data polarization detailed foreground instrumental models, allowing further checks enhanced immunity systematics. Progress in modelling enables larger sky fraction. Improvements processing models...
We discuss the measurements of galaxy cluster mass functions at z ≈ 0.05 and 0.5 using high-quality Chandra observations samples derived from ROSAT PSPC All-Sky 400 deg2 surveys. provide a full reference for data analysis procedures, present updated calibration relations between total its X-ray indicators (TX, Mgas, YX) based on subsample low-z relaxed clusters, first measurement evolving LX–Mtot relation (with Mtot estimated obtained well defined statistically complete sample with...
We study the implications of Planck data for models dark energy (DE) and modified gravity (MG), beyond cosmological constant scenario. start with cases where DE only directly affects background evolution, considering Taylor expansions equation state, principal component analysis parameterizations related to potential a minimally coupled scalar field. When estimating density at early times, we significantly improve present constraints. then move general or MG perturbations that encompass both...
We present cluster counts and corresponding cosmological constraints from the Planck full mission data set. Our catalogue consists of 439 clusters detected via their Sunyaev-Zeldovich (SZ) signal down to a signal-to-noise ratio 6, is more than factor 2 larger 2013 cosmology sample. The are consistent with those yield compatible under same modelling assumptions. Taking advantage catalogue, we extend our analysis two-dimensional distribution in redshift signal-to-noise. use mass estimates two...
The two fundamental assumptions of the standard cosmological model - that initial fluctuations are statistically isotropic and Gaussian rigorously tested using maps cosmic microwave background (CMB) anisotropy from Planck satellite. Deviations isotropy have been found demonstrated to be robust against component separation algorithm, mask choice frequency dependence. Many these anomalies were previously observed in WMAP data, now confirmed at similar levels significance (about 3 sigma)....
The Planck nominal mission cosmic microwave background (CMB) maps yield unprecedented constraints on primordial non-Gaussianity (NG). Using three optimal bispectrum estimators, separable template-fitting (KSW), binned, and modal, we obtain consistent values for the local, equilateral, orthogonal amplitudes, quoting as our final result fNL^local= 2.7+/-5.8, fNL^equil= -42+/-75, fNL^ortho= -25+\-39 (68% CL statistical). NG is detected in data; using skew-C_l statistics find a nonzero from...
The Planck full mission cosmic microwave background(CMB) temperature and E-mode polarization maps are analysed to obtain constraints on primordial non-Gaussianity(NG). Using three classes of optimal bispectrum estimators - separable template-fitting (KSW), binned, modal we consistent values for the local, equilateral, orthogonal amplitudes, quoting as our final result from alone fNL^local=2.5+\-5.7, fNL^equil=-16+\-70 fNL^ortho=-34+\-33(68%CL). Combining data fNL^local=0.8+\-5.0,...
We present the Planck likelihood, a complete statistical description of two-point correlation function CMB temperature fluctuations. use this likelihood to derive power spectrum over three decades in l, covering 2 <= l 2500. The main source error at 1500 is cosmic variance. Uncertainties small-scale foreground modelling and instrumental noise dominate budget higher l's. For < 50, our exploits all frequency channels from 30 353 GHz through physically motivated Bayesian component separation...
Planck has mapped the microwave sky in nine frequency bands between 30 and 857 GHz temperature seven 353 polarization. In this paper we consider problem of diffuse astrophysical component separation, process these maps within a Bayesian framework to derive consistent set full-sky maps. For analysis, combine observations with 9-year WMAP Haslam et al. 408 MHz map joint model CMB, synchrotron, free-free, spinning dust, CO, line emission 94 100 channels, thermal dust emission. Full-sky are...
The JEM–X monitor provides X-ray spectra and imaging with arcminute angular resolution in the 3 to 35 keV band. good low energy response of plays an important role identification gamma ray sources analysis scientific interpretation combined data. is a coded aperture instrument consisting two identical, coaligned telescopes. Each detectors has sensitive area 500 cm2, views sky through its own mask. masks are inverted respect each other 3' across effective field view about 10° diameter.
We present the most significant measurement of cosmic microwave background (CMB) lensing potential to date (at a level 40 sigma), using temperature and polarization data from Planck 2015 full-mission release. Using polarization-only estimator we detect at significance 5 sigma. cross-check accuracy our wide frequency coverage complementarity measurements. Public products based on this include an estimate over approximately 70% sky, power spectrum in bandpowers for multipole range