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Primordial non-Gaussianity (PNG) in Large Scale Structures is obfuscated by the many additional sources of non-linearity. Within the Effective Field Theory approach to Standard Perturbation Theory, we show that matter non-linearities in the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Yvette Welling , Drian van der Woude , Enrico Pajer

Cosmic microwave background (CMB) temperature anisotropies follow a Gaussian statistical distribution in the standard inflationary model, but there are non-Gaussian contributions due to astrophysical foregrounds. The detection of the…

Astrophysics · Physics 2009-11-11 F. Argueso , J. L. Sanz , R. B. Barreiro , D. Herranz , J. Gonzalez-Nuevo

The Large Area Telescope (LAT) onboard the Fermi satellite is exploring the gamma-ray sky in the energy range above 20MeV. We have developed a method to reconstruct the energy spectra of the gamma rays detected by the Fermi LAT instrument…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 M. N. Mazziotta

The Fermi Large Area Telescope First Source Catalog (1FGL) provided spatial, spectral, and temporal properties for a large number of gamma-ray sources using a uniform analysis method. After correlating with the most-complete catalogs of…

High Energy Astrophysical Phenomena · Physics 2015-05-30 LAT Collaboration

We present a new method to characterize unresolved point sources (PSs), generalizing traditional template fits to account for non-Poissonian photon statistics. We apply this method to Fermi Large Area Telescope gamma-ray data to…

High Energy Astrophysical Phenomena · Physics 2016-02-10 Samuel K. Lee , Mariangela Lisanti , Benjamin R. Safdi , Tracy R. Slatyer , Wei Xue

We present SkyFACT (Sky Factorization with Adaptive Constrained Templates), a new approach for studying, modeling and decomposing diffuse gamma-ray emission. Like most previous analyses, the approach relies on predictions from cosmic-ray…

High Energy Astrophysical Phenomena · Physics 2017-08-22 Emma Storm , Christoph Weniger , Francesca Calore

The Galactic Center GeV excess (GCE) has garnered great interest as a possible signal of either dark matter annihilation or some novel astrophysical phenomenon, such as a new population of gamma-ray emitting pulsars. In a companion paper,…

High Energy Astrophysical Phenomena · Physics 2020-09-23 Rebecca K. Leane , Tracy R. Slatyer

Previous studies determining which astronomical photometry software is best suited for a particular dataset are usually focused on speed, source classification, and/or meeting a sensitivity requirement. For faint objects in particular, the…

Instrumentation and Methods for Astrophysics · Physics 2013-05-27 Sarah Sonnett , Karen Meech , Robert Jedicke , Schelte Bus , John Tonry , Olivier Hainaut

Data from the Fermi Large Area Telescope suggests that there is an extended excess of GeV gamma-ray photons in the Inner Galaxy. Identifying potential astrophysical sources that contribute to this excess is an important step in verifying…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Samuel K. Lee , Mariangela Lisanti , Benjamin R. Safdi

A significant point-like component from the small scale (or discrete) structure in the H2 interstellar gas might be present in the Fermi-LAT data, but modeling this emission relies on observations of rare gas tracers only available in…

High Energy Astrophysical Phenomena · Physics 2023-03-29 Alexander Shmakov , Mohammadamin Tavakoli , Pierre Baldi , Christopher M. Karwin , Alex Broughton , Simona Murgia

Recent claims of a gamma-ray excess in the diffuse galactic emission detected by the Fermi Large Area Telescope with a morphology similar to the WMAP haze were based on the assumption that spatial templates of the interstellar medium (ISM)…

Astrophysics of Galaxies · Physics 2010-04-16 Tim Linden , Stefano Profumo

During its first 2 years of mission the Fermi-LAT instrument discovered more than 1,800 gamma-ray sources in the 100 MeV to 100 GeV range. Despite the application of advanced techniques to identify and associate the Fermi-LAT sources with…

High Energy Astrophysical Phenomena · Physics 2016-03-02 David Salvetti

We describe the development of the model for interstellar gamma-ray emission that is the standard adopted by the LAT team and is publicly available. The model is based on a linear combination of templates for interstellar gas column density…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Jean-Marc Casandjian

The ntCT nano tomography system is a geometrically magnifying X-ray microscopy system integrating the recent Excillum NanoTube nano-focus X-ray source and a CdTe photon counting detector from Dectris. The system's modulation transfer…

Instrumentation and Detectors · Physics 2021-02-01 Jonas Graetz , Dominik Müller , Andreas Balles , Christian Fella

We study the capabilities of the Fermi-LAT instrument on board of the Fermi mission to constrain particle dark matter properties, as annihilation cross section, mass and branching ratio into dominant annihilation channels, with gamma-ray…

High Energy Astrophysical Phenomena · Physics 2017-02-22 Nicolas Bernal , Sergio Palomares-Ruiz

In this paper we analyze the biasing effect of point sources, either thermal Sunyaev-Zeldovich clusters or standard radio sources, on the estimated strength of the non-Gaussianity in the Cosmic Microwave Background (CMB). We show that the…

Astrophysics · Physics 2008-11-26 Daniel Babich , Elena Pierpaoli

Adaptive optics (AO) restore the angular resolution of ground-based telescopes, but at the cost of delivering a time- and space-varying point spread function (PSF) with a complex shape. PSF knowledge is crucial for breaking existing limits…

Instrumentation and Methods for Astrophysics · Physics 2018-04-17 O. Beltramo-Martin , C. M. Correia , E. Mieda , B. Neichel , T. Fusco , G. Witzel , J. Lu , J. -P. Véran

We present a novel graphical framework for modeling non-negative sequential data with hierarchical structure. Our model corresponds to a network of coupled non-negative matrix factorization (NMF) modules, which we refer to as a positive…

Machine Learning · Computer Science 2009-07-16 Brian K. Vogel

Statistical evidence has previously suggested that the Galactic Center GeV Excess (GCE) originates largely from point sources, and not from annihilating dark matter. We examine the impact of unmodeled source populations on identifying the…

High Energy Astrophysical Phenomena · Physics 2019-12-18 Rebecca K. Leane , Tracy R. Slatyer

Procedures based on current methods to detect sources in X-ray images are applied to simulated XMM images. All significant instrumental effects are taken into account, and two kinds of sources are considered -- unresolved sources…

Astrophysics · Physics 2009-11-06 I. Valtchanov , M. Pierre , R. Gastaud