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Book ; Online: Extracting the gamma-ray source-count distribution below the Fermi-LAT detection limit with deep learning

Amerio, Aurelio / Cuoco, Alessandro / Fornengo, Nicolao

2023

Abstract: We reconstruct the extra-galactic gamma-ray source-count distribution, or $dN/dS$, of resolved and unresolved sources by adopting machine learning techniques. Specifically, we train a convolutional neural network on synthetic 2-dimensional sky-maps, ... ...

Abstract	We reconstruct the extra-galactic gamma-ray source-count distribution, or $dN/dS$, of resolved and unresolved sources by adopting machine learning techniques. Specifically, we train a convolutional neural network on synthetic 2-dimensional sky-maps, which are built by varying parameters of underlying source-counts models and incorporate the Fermi-LAT instrumental response functions. The trained neural network is then applied to the Fermi-LAT data, from which we estimate the source count distribution down to flux levels a factor of 50 below the Fermi-LAT threshold. We perform our analysis using 14 years of data collected in the $(1,10)$ GeV energy range. The results we obtain show a source count distribution which, in the resolved regime, is in excellent agreement with the one derived from catalogued sources, and then extends as $dN/dS \sim S^{-2}$ in the unresolved regime, down to fluxes of $5 \cdot 10^{-12}$ cm$^{-2}$ s$^{-1}$. The neural network architecture and the devised methodology have the flexibility to enable future analyses to study the energy dependence of the source-count distribution. Comment: 25 pages + Appendix, 24 figures
Keywords	Astrophysics - Cosmology and Nongalactic Astrophysics ; Astrophysics - High Energy Astrophysical Phenomena ; Astrophysics - Instrumentation and Methods for Astrophysics ; Computer Science - Machine Learning
Subject code	520
Publishing date	2023-02-03
Publishing country	us
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Possibility of a dark matter interpretation for the excess in isotropic radio emission reported by ARCADE.

Fornengo, N / Lineros, R / Regis, M / Taoso, M

Physical review letters

2011 Volume 107, Issue 27, Page(s) 271302

Abstract: The ARCADE 2 Collaboration has recently measured an isotropic radio emission which is significantly brighter than the expected contributions from known extra-galactic sources. The simplest explanation of such excess involves a "new" population of ... ...

Abstract	The ARCADE 2 Collaboration has recently measured an isotropic radio emission which is significantly brighter than the expected contributions from known extra-galactic sources. The simplest explanation of such excess involves a "new" population of unresolved sources which become the most numerous at very low (observationally unreached) brightness. We investigate this scenario in terms of synchrotron radiation induced by weakly interacting massive particle (WIMP) annihilations or decays in extra-galactic halos. Intriguingly, for light-mass WIMPs with a thermal annihilation cross section, the level of expected radio emission matches the ARCADE observations.
Language	English
Publishing date	2011-12-30
Publishing country	United States
Document type	Journal Article
ZDB-ID	208853-8
ISSN	1079-7114 ; 0031-9007
ISSN (online)	1079-7114
ISSN	0031-9007
DOI	10.1103/PhysRevLett.107.271302
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Article ; Online: Particle Dark Matter Searches Outside the Local Group.

Regis, Marco / Xia, Jun-Qing / Cuoco, Alessandro / Branchini, Enzo / Fornengo, Nicolao / Viel, Matteo

Physical review letters

2015 Volume 114, Issue 24, Page(s) 241301

Abstract: If dark matter (DM) is composed by particles which are nongravitationally coupled to ordinary matter, their annihilations or decays in cosmic structures can result in detectable radiation. We show that the most powerful technique to detect a particle DM ... ...

Abstract	If dark matter (DM) is composed by particles which are nongravitationally coupled to ordinary matter, their annihilations or decays in cosmic structures can result in detectable radiation. We show that the most powerful technique to detect a particle DM signal outside the Local Group is to study the angular cross-correlation of nongravitational signals with low-redshift gravitational probes. This method allows us to enhance the signal to noise from the regions of the Universe where the DM-induced emission is preferentially generated. We demonstrate the power of this approach by focusing on GeV-TeV DM and on the recent cross-correlation analysis between the 2MASS galaxy catalogue and the Fermi-LAT γ-ray maps. We show that this technique is more sensitive than other extragalactic γ-ray probes, such as the energy spectrum and angular autocorrelation of the extragalactic background, and emission from clusters of galaxies. Intriguingly, we find that the measured cross-correlation can be well fitted by a DM component, with a thermal annihilation cross section and mass between 10 and 100 GeV, depending on the small-scale DM properties and γ-ray production mechanism. This solicits further data collection and dedicated analyses.
Language	English
Publishing date	2015-06-19
Publishing country	United States
Document type	Journal Article
ZDB-ID	208853-8
ISSN	1079-7114 ; 0031-9007
ISSN (online)	1079-7114
ISSN	0031-9007
DOI	10.1103/PhysRevLett.114.241301
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Article: Minimal supergravity scalar neutrino dark matter and inverse seesaw neutrino masses.

Arina, C / Bazzocchi, F / Fornengo, N / Romao, J C / Valle, J W F

Physical review letters

2008 Volume 101, Issue 16, Page(s) 161802

Abstract: We show that within the inverse seesaw mechanism for generating neutrino masses, minimal supergravity naturally provides the scalar neutrino as the lightest superparticle. We also demonstrate that such schemes naturally reconcile the small neutrino ... ...

Abstract	We show that within the inverse seesaw mechanism for generating neutrino masses, minimal supergravity naturally provides the scalar neutrino as the lightest superparticle. We also demonstrate that such schemes naturally reconcile the small neutrino masses with the correct relic scalar neutrino dark matter abundance and accessible direct detection rates in nuclear recoil experiments. This way, inverse seesaw minimal supergravity offers a common solution to the generation of the neutrino mass and to the origin of dark matter.
Language	English
Publishing date	2008-10-17
Publishing country	United States
Document type	Journal Article
ZDB-ID	208853-8
ISSN	1079-7114 ; 0031-9007
ISSN (online)	1079-7114
ISSN	0031-9007
DOI	10.1103/PhysRevLett.101.161802
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Article ; Online: Cosmic-ray antinuclei as messengers of new physics: status and outlook for the new decade.

von Doetinchem, P / Perez, K / Aramaki, T / Baker, S / Barwick, S / Bird, R / Boezio, M / Boggs, S E / Cui, M / Datta, A / Donato, F / Evoli, C / Fabris, L / Fabbietti, L / Ferronato Bueno, E / Fornengo, N / Fuke, H / Gerrity, C / Gomez Coral, D /

Hailey, C / Hooper, D / Kachelriess, M / Korsmeier, M / Kozai, M / Lea, R / Li, N / Lowell, A / Manghisoni, M / Moskalenko, I V / Munini, R / Naskret, M / Nelson, T / Ng, K C Y / Nozzoli, F / Oliva, A / Ong, R A / Osteria, G / Pierog, T / Poulin, V / Profumo, S / Pöschl, T / Quinn, S / Re, V / Rogers, F / Ryan, J / Saffold, N / Sakai, K / Salati, P / Schael, S / Serksnyte, L / Shukla, A / Stoessl, A / Tjemsland, J / Vannuccini, E / Vecchi, M / Winkler, M W / Wright, D / Xiao, M / Xu, W / Yoshida, T / Zampa, G / Zuccon, P

Journal of cosmology and astroparticle physics

2020 Volume 2020

Abstract: The precise measurement of cosmic-ray antinuclei serves as an important means for identifying the nature of dark matter and other new astrophysical phenomena, and could be used with other cosmic-ray species to understand cosmic-ray production and ... ...

Abstract	The precise measurement of cosmic-ray antinuclei serves as an important means for identifying the nature of dark matter and other new astrophysical phenomena, and could be used with other cosmic-ray species to understand cosmic-ray production and propagation in the Galaxy. For instance, low-energy antideuterons would provide a "smoking gun" signature of dark matter annihilation or decay, essentially free of astrophysical background. Studies in recent years have emphasized that models for cosmic-ray antideuterons must be considered together with the abundant cosmic antiprotons and any potential observation of antihelium. Therefore, a second dedicated Antideuteron Workshop was organized at UCLA in March 2019, bringing together a community of theorists and experimentalists to review the status of current observations of cosmic-ray antinuclei, the theoretical work towards understanding these signatures, and the potential of upcoming measurements to illuminate ongoing controversies. This review aims to synthesize this recent work and present implications for the upcoming decade of antinuclei observations and searches. This includes discussion of a possible dark matter signature in the AMS-02 antiproton spectrum, the most recent limits from BESS Polar-II on the cosmic antideuteron flux, and reports of candidate antihelium events by AMS-02; recent collider and cosmic-ray measurements relevant for antinuclei production models; the state of cosmic-ray transport models in light of AMS-02 and Voyager data; and the prospects for upcoming experiments, such as GAPS. This provides a roadmap for progress on cosmic antinuclei signatures of dark matter in the coming years.
Language	English
Publishing date	2020-08-18
Publishing country	England
Document type	Journal Article
ISSN	1475-7516
ISSN (online)	1475-7516
DOI	10.1088/1475-7516/2020/08/035
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Limits on the neutrino mass and mixing angle from pion and lepton decays.

Bottino / Fornengo / Kim / Mignola

Physical review. D, Particles and fields

1996 Volume 53, Issue 11, Page(s) 6361–6373

Language	English
Publishing date	1996-06
Publishing country	United States
Document type	Journal Article
ZDB-ID	209772-2
ISSN	0556-2821 ; 2470-0010 ; 1550-7998
ISSN	0556-2821 ; 2470-0010 ; 1550-7998
DOI	10.1103/physrevd.53.6361
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Detection of Cross-Correlation between Gravitational Lensing and γ Rays.

Ammazzalorso, S / Gruen, D / Regis, M / Camera, S / Ando, S / Fornengo, N / Bechtol, K / Bridle, S L / Choi, A / Eifler, T F / Gatti, M / MacCrann, N / Omori, Y / Samuroff, S / Sheldon, E / Troxel, M A / Zuntz, J / Carrasco Kind, M / Annis, J /

Avila, S / Bertin, E / Brooks, D / Burke, D L / Carnero Rosell, A / Carretero, J / Castander, F J / Costanzi, M / da Costa, L N / De Vicente, J / Desai, S / Diehl, H T / Dietrich, J P / Doel, P / Everett, S / Flaugher, B / Fosalba, P / García-Bellido, J / Gaztanaga, E / Gerdes, D W / Giannantonio, T / Goldstein, D A / Gruendl, R A / Gutierrez, G / Hollowood, D L / Honscheid, K / James, D J / Jarvis, M / Jeltema, T / Kent, S / Kuropatkin, N / Lahav, O / Li, T S / Lima, M / Maia, M A G / Marshall, J L / Melchior, P / Menanteau, F / Miquel, R / Ogando, R L C / Palmese, A / Plazas, A A / Romer, A K / Roodman, A / Rykoff, E S / Sánchez, C / Sanchez, E / Scarpine, V / Serrano, S / Sevilla-Noarbe, I / Smith, M / Soares-Santos, M / Sobreira, F / Suchyta, E / Swanson, M E C / Tarle, G / Thomas, D / Vikram, V / Zhang, Y

Physical review letters

2020 Volume 124, Issue 10, Page(s) 101102

Abstract: In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to ...

Abstract	In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.
Language	English
Publishing date	2020-03-26
Publishing country	United States
Document type	Journal Article
ZDB-ID	208853-8
ISSN	1079-7114 ; 0031-9007
ISSN (online)	1079-7114
ISSN	0031-9007
DOI	10.1103/PhysRevLett.124.101102
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Unresolved Gamma-Ray Sky through its Angular Power Spectrum.

Ackermann, M / Ajello, M / Baldini, L / Ballet, J / Barbiellini, G / Bastieri, D / Bellazzini, R / Bissaldi, E / Blandford, R D / Bonino, R / Bottacini, E / Bregeon, J / Bruel, P / Buehler, R / Burns, E / Buson, S / Cameron, R A / Caputo, R / Caraveo, P A /

Cavazzuti, E / Chen, S / Chiaro, G / Ciprini, S / Costantin, D / Cuoco, A / Cutini, S / D'Ammando, F / de la Torre Luque, P / de Palma, F / Desai, A / Digel, S W / Di Lalla, N / Di Mauro, M / Di Venere, L / Fana Dirirsa, F / Favuzzi, C / Franckowiak, A / Fukazawa, Y / Funk, S / Fusco, P / Gargano, F / Gasparrini, D / Giglietto, N / Giordano, F / Giroletti, M / Green, D / Grenier, I A / Guillemot, L / Guiriec, S / Horan, D / Jóhannesson, G / Kuss, M / Larsson, S / Latronico, L / Li, J / Liodakis, I / Longo, F / Loparco, F / Lubrano, P / Magill, J D / Maldera, S / Malyshev, D / Manfreda, A / Mazziotta, M N / Mereu, I / Michelson, P F / Mitthumsiri, W / Mizuno, T / Monzani, M E / Morselli, A / Moskalenko, I V / Negro, M / Nuss, E / Orienti, M / Orlando, E / Palatiello, M / Paliya, V S / Paneque, D / Persic, M / Pesce-Rollins, M / Petrosian, V / Piron, F / Porter, T A / Principe, G / Rainò, S / Rando, R / Razzano, M / Razzaque, S / Reimer, A / Reimer, O / Serini, D / Sgrò, C / Siskind, E J / Spandre, G / Spinelli, P / Suson, D J / Tajima, H / Takahashi, M / Thayer, J B / Tibaldo, L / Torres, D F / Troja, E / Venters, T M / Vianello, G / Wood, K / Yassine, M / Zaharijas, G / Ammazzalorso, S / Fornengo, N / Regis, M

Physical review letters

2019 Volume 121, Issue 24, Page(s) 241101

Abstract: The gamma-ray sky has been observed with unprecedented accuracy in the last decade by the Fermi -large area telescope (LAT), allowing us to resolve and understand the high-energy Universe. The nature of the remaining unresolved emission [unresolved gamma- ...

Abstract	The gamma-ray sky has been observed with unprecedented accuracy in the last decade by the Fermi -large area telescope (LAT), allowing us to resolve and understand the high-energy Universe. The nature of the remaining unresolved emission [unresolved gamma-ray background (UGRB)] below the LAT source detection threshold can be uncovered by characterizing the amplitude and angular scale of the UGRB fluctuation field. This Letter presents a measurement of the UGRB autocorrelation angular power spectrum based on eight years of Fermi-LAT Pass 8 data products. The analysis is designed to be robust against contamination from resolved sources and noise systematics. The sensitivity to subthreshold sources is greatly enhanced with respect to previous measurements. We find evidence (with ∼3.7σ significance) that the scenario in which two classes of sources contribute to the UGRB signal is favored over a single class. A double power law with exponential cutoff can explain the anisotropy energy spectrum well, with photon indices of the two populations being 2.55±0.23 and 1.86±0.15.
Language	English
Publishing date	2019-01-04
Publishing country	United States
Document type	Journal Article
ZDB-ID	208853-8
ISSN	1079-7114 ; 0031-9007
ISSN (online)	1079-7114
ISSN	0031-9007
DOI	10.1103/PhysRevLett.121.241101
Database	MEDical Literature Analysis and Retrieval System OnLINE

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